doc/src/sgml/information_schema.sgml

   1 <!-- $PostgreSQL$ -->
   2
   3 <chapter id="information-schema">
   4  <title>The Information Schema</title>
   5
   6  <indexterm zone="information-schema">
   7   <primary>information schema</primary>
   8  </indexterm>
   9
  10  <para>
  11   The information schema consists of a set of views that contain
  12   information about the objects defined in the current database.  The
  13   information schema is defined in the SQL standard and can therefore
  14   be expected to be portable and remain stable &mdash; unlike the system
  15   catalogs, which are specific to
  16   <productname>PostgreSQL</productname> and are modelled after
  17   implementation concerns.  The information schema views do not,
  18   however, contain information about
  19   <productname>PostgreSQL</productname>-specific features; to inquire
  20   about those you need to query the system catalogs or other
  21   <productname>PostgreSQL</productname>-specific views.
  22  </para>
  23
  24  <sect1 id="infoschema-schema">
  25   <title>The Schema</title>
  26
  27   <para>
  28    The information schema itself is a schema named
  29    <literal>information_schema</literal>.  This schema automatically
  30    exists in all databases.  The owner of this schema is the initial
  31    database user in the cluster, and that user naturally has all the
  32    privileges on this schema, including the ability to drop it (but
  33    the space savings achieved by that are minuscule).
  34   </para>
  35
  36   <para>
  37    By default, the information schema is not in the schema search
  38    path, so you need to access all objects in it through qualified
  39    names.  Since the names of some of the objects in the information
  40    schema are generic names that might occur in user applications, you
  41    should be careful if you want to put the information schema in the
  42    path.
  43   </para>
  44  </sect1>
  45
  46  <sect1 id="infoschema-datatypes">
  47   <title>Data Types</title>
  48
  49   <para>
  50    The columns of the information schema views use special data types
  51    that are defined in the information schema.  These are defined as
  52    simple domains over ordinary built-in types.  You should not use
  53    these types for work outside the information schema, but your
  54    applications must be prepared for them if they select from the
  55    information schema.
  56   </para>
  57
  58   <para>
  59    These types are:
  60
  61    <variablelist>
  62     <varlistentry>
  63      <term><type>cardinal_number</type></term>
  64      <listitem>
  65       <para>
  66        A nonnegative integer.
  67       </para>
  68      </listitem>
  69     </varlistentry>
  70
  71     <varlistentry>
  72      <term><type>character_data</type></term>
  73      <listitem>
  74       <para>
  75        A character string (without specific maximum length).
  76       </para>
  77      </listitem>
  78     </varlistentry>
  79
  80     <varlistentry>
  81      <term><type>sql_identifier</type></term>
  82      <listitem>
  83       <para>
  84        A character string.  This type is used for SQL identifiers, the
  85        type <type>character_data</type> is used for any other kind of
  86        text data.
  87       </para>
  88      </listitem>
  89     </varlistentry>
  90
  91     <varlistentry>
  92      <term><type>time_stamp</type></term>
  93      <listitem>
  94       <para>
  95        A domain over the type <type>timestamp with time zone</type>
  96       </para>
  97      </listitem>
  98     </varlistentry>
  99    </variablelist>
 100
 101    Every column in the information schema has one of these four types.
 102   </para>
 103
 104   <para>
 105    Boolean (true/false) data is represented in the information schema
 106    by a column of type <type>character_data</type> that contains
 107    either <literal>YES</literal> or <literal>NO</literal>.  (The
 108    information schema was invented before the type
 109    <type>boolean</type> was added to the SQL standard, so this
 110    convention is necessary to keep the information schema backward
 111    compatible.)
 112   </para>
 113  </sect1>
 114
 115  <sect1 id="infoschema-information-schema-catalog-name">
 116   <title><literal>information_schema_catalog_name</literal></title>
 117
 118   <para>
 119    <literal>information_schema_catalog_name</literal> is a table that
 120    always contains one row and one column containing the name of the
 121    current database (current catalog, in SQL terminology).
 122   </para>
 123
 124   <table>
 125    <title><literal>information_schema_catalog_name</literal> Columns</title>
 126
 127    <tgroup cols="3">
 128     <thead>
 129      <row>
 130       <entry>Name</entry>
 131       <entry>Data Type</entry>
 132       <entry>Description</entry>
 133      </row>
 134     </thead>
 135
 136     <tbody>
 137      <row>
 138       <entry><literal>catalog_name</literal></entry>
 139       <entry><type>sql_identifier</type></entry>
 140       <entry>Name of the database that contains this information schema</entry>
 141      </row>
 142     </tbody>
 143    </tgroup>
 144   </table>
 145  </sect1>
 146
 147  <sect1 id="infoschema-administrable-role-authorizations">
 148   <title><literal>administrable_role_authorizations</literal></title>
 149
 150   <para>
 151    The view <literal>administrable_role_authorizations</literal>
 152    identifies all roles that the current user has the admin option
 153    for.
 154   </para>
 155
 156   <table>
 157    <title><literal>administrable_role_authorizations</literal> Columns</title>
 158
 159    <tgroup cols="3">
 160     <thead>
 161      <row>
 162       <entry>Name</entry>
 163       <entry>Data Type</entry>
 164       <entry>Description</entry>
 165      </row>
 166     </thead>
 167
 168     <tbody>
 169      <row>
 170       <entry><literal>grantee</literal></entry>
 171       <entry><type>sql_identifier</type></entry>
 172       <entry>
 173        Name of the role to which this role membership was granted (can
 174        be the current user, or a different role in case of nested role
 175        memberships)
 176       </entry>
 177      </row>
 178
 179      <row>
 180       <entry><literal>role_name</literal></entry>
 181       <entry><type>sql_identifier</type></entry>
 182       <entry>Name of a role</entry>
 183      </row>
 184
 185      <row>
 186       <entry><literal>is_grantable</literal></entry>
 187       <entry><type>character_data</type></entry>
 188       <entry>Always <literal>YES</literal></entry>
 189      </row>
 190     </tbody>
 191    </tgroup>
 192   </table>
 193  </sect1>
 194
 195  <sect1 id="infoschema-applicable-roles">
 196   <title><literal>applicable_roles</literal></title>
 197
 198   <para>
 199    The view <literal>applicable_roles</literal> identifies all roles
 200    whose privileges the current user can use.  This means there is
 201    some chain of role grants from the current user to the role in
 202    question.  The current user itself is also an applicable role.  The
 203    set of applicable roles is generally used for permission checking.
 204    <indexterm><primary>applicable role</primary></indexterm>
 205    <indexterm><primary>role</primary><secondary>applicable</secondary></indexterm>
 206   </para>
 207
 208   <table>
 209    <title><literal>applicable_roles</literal> Columns</title>
 210
 211    <tgroup cols="3">
 212     <thead>
 213      <row>
 214       <entry>Name</entry>
 215       <entry>Data Type</entry>
 216       <entry>Description</entry>
 217      </row>
 218     </thead>
 219
 220     <tbody>
 221      <row>
 222       <entry><literal>grantee</literal></entry>
 223       <entry><type>sql_identifier</type></entry>
 224       <entry>
 225        Name of the role to which this role membership was granted (can
 226        be the current user, or a different role in case of nested role
 227        memberships)
 228       </entry>
 229      </row>
 230
 231      <row>
 232       <entry><literal>role_name</literal></entry>
 233       <entry><type>sql_identifier</type></entry>
 234       <entry>Name of a role</entry>
 235      </row>
 236
 237      <row>
 238       <entry><literal>is_grantable</literal></entry>
 239       <entry><type>character_data</type></entry>
 240       <entry>
 241        <literal>YES</literal> if the grantee has the admin option on
 242        the role, <literal>NO</literal> if not
 243       </entry>
 244      </row>
 245     </tbody>
 246    </tgroup>
 247   </table>
 248  </sect1>
 249
 250  <sect1 id="infoschema-attributes">
 251   <title><literal>attributes</literal></title>
 252
 253   <para>
 254    The view <literal>attributes</literal> contains information about
 255    the attributes of composite data types defined in the database.
 256    (Note that the view does not give information about table columns,
 257    which are sometimes called attributes in PostgreSQL contexts.)
 258   </para>
 259
 260   <table>
 261    <title><literal>attributes</literal> Columns</title>
 262
 263    <tgroup cols="3">
 264     <thead>
 265      <row>
 266       <entry>Name</entry>
 267       <entry>Data Type</entry>
 268       <entry>Description</entry>
 269      </row>
 270     </thead>
 271
 272     <tbody>
 273      <row>
 274       <entry><literal>udt_catalog</literal></entry>
 275       <entry><type>sql_identifier</type></entry>
 276       <entry>Name of the database containing the data type (always the current database)</entry>
 277      </row>
 278
 279      <row>
 280       <entry><literal>udt_schema</literal></entry>
 281       <entry><type>sql_identifier</type></entry>
 282       <entry>Name of the schema containing the data type</entry>
 283      </row>
 284
 285      <row>
 286       <entry><literal>udt_name</literal></entry>
 287       <entry><type>sql_identifier</type></entry>
 288       <entry>Name of the data type</entry>
 289      </row>
 290
 291      <row>
 292       <entry><literal>attribute_name</literal></entry>
 293       <entry><type>sql_identifier</type></entry>
 294       <entry>Name of the attribute</entry>
 295      </row>
 296
 297      <row>
 298       <entry><literal>ordinal_position</literal></entry>
 299       <entry><type>cardinal_number</type></entry>
 300       <entry>Ordinal position of the attribute within the data type (count starts at 1)</entry>
 301      </row>
 302
 303      <row>
 304       <entry><literal>attribute_default</literal></entry>
 305       <entry><type>character_data</type></entry>
 306       <entry>Default expression of the attribute</entry>
 307      </row>
 308
 309      <row>
 310       <entry><literal>is_nullable</literal></entry>
 311       <entry><type>character_data</type></entry>
 312       <entry>
 313        <literal>YES</literal> if the attribute is possibly nullable,
 314        <literal>NO</literal> if it is known not nullable.
 315       </entry>
 316      </row>
 317
 318      <row>
 319       <entry><literal>data_type</literal></entry>
 320       <entry><type>character_data</type></entry>
 321       <entry>
 322        Data type of the attribute, if it is a built-in type, or
 323        <literal>ARRAY</literal> if it is some array (in that case, see
 324        the view <literal>element_types</literal>), else
 325        <literal>USER-DEFINED</literal> (in that case, the type is
 326        identified in <literal>attribute_udt_name</literal> and
 327        associated columns).
 328       </entry>
 329      </row>
 330
 331      <row>
 332       <entry><literal>character_maximum_length</literal></entry>
 333       <entry><type>cardinal_number</type></entry>
 334       <entry>
 335        If <literal>data_type</literal> identifies a character or bit
 336        string type, the declared maximum length; null for all other
 337        data types or if no maximum length was declared.
 338       </entry>
 339      </row>
 340
 341      <row>
 342       <entry><literal>character_octet_length</literal></entry>
 343       <entry><type>cardinal_number</type></entry>
 344       <entry>
 345        If <literal>data_type</literal> identifies a character type,
 346        the maximum possible length in octets (bytes) of a datum (this
 347        should not be of concern to
 348        <productname>PostgreSQL</productname> users); null for all
 349        other data types.
 350       </entry>
 351      </row>
 352
 353      <row>
 354       <entry><literal>numeric_precision</literal></entry>
 355       <entry><type>cardinal_number</type></entry>
 356       <entry>
 357        If <literal>data_type</literal> identifies a numeric type, this
 358        column contains the (declared or implicit) precision of the
 359        type for this attribute.  The precision indicates the number of
 360        significant digits.  It can be expressed in decimal (base 10)
 361        or binary (base 2) terms, as specified in the column
 362        <literal>numeric_precision_radix</literal>.  For all other data
 363        types, this column is null.
 364       </entry>
 365      </row>
 366
 367      <row>
 368       <entry><literal>numeric_precision_radix</literal></entry>
 369       <entry><type>cardinal_number</type></entry>
 370       <entry>
 371        If <literal>data_type</literal> identifies a numeric type, this
 372        column indicates in which base the values in the columns
 373        <literal>numeric_precision</literal> and
 374        <literal>numeric_scale</literal> are expressed.  The value is
 375        either 2 or 10.  For all other data types, this column is null.
 376       </entry>
 377      </row>
 378
 379      <row>
 380       <entry><literal>numeric_scale</literal></entry>
 381       <entry><type>cardinal_number</type></entry>
 382       <entry>
 383        If <literal>data_type</literal> identifies an exact numeric
 384        type, this column contains the (declared or implicit) scale of
 385        the type for this attribute.  The scale indicates the number of
 386        significant digits to the right of the decimal point.  It can
 387        be expressed in decimal (base 10) or binary (base 2) terms, as
 388        specified in the column
 389        <literal>numeric_precision_radix</literal>.  For all other data
 390        types, this column is null.
 391       </entry>
 392      </row>
 393
 394      <row>
 395       <entry><literal>datetime_precision</literal></entry>
 396       <entry><type>cardinal_number</type></entry>
 397       <entry>
 398        If <literal>data_type</literal> identifies a date, time,
 399        timestamp, or interval type, this column contains the (declared
 400        or implicit) fractional seconds precision of the type for this
 401        attribute, that is, the number of decimal digits maintained
 402        following the decimal point in the seconds value.  For all
 403        other data types, this column is null.
 404       </entry>
 405      </row>
 406
 407      <row>
 408       <entry><literal>interval_type</literal></entry>
 409       <entry><type>character_data</type></entry>
 410       <entry>Not yet implemented</entry>
 411      </row>
 412
 413      <row>
 414       <entry><literal>interval_precision</literal></entry>
 415       <entry><type>character_data</type></entry>
 416       <entry>Not yet implemented</entry>
 417      </row>
 418
 419      <row>
 420       <entry><literal>attribute_udt_catalog</literal></entry>
 421       <entry><type>sql_identifier</type></entry>
 422       <entry>
 423        Name of the database that the attribute data type is defined in
 424        (always the current database)
 425       </entry>
 426      </row>
 427
 428      <row>
 429       <entry><literal>attribute_udt_schema</literal></entry>
 430       <entry><type>sql_identifier</type></entry>
 431       <entry>
 432        Name of the schema that the attribute data type is defined in
 433       </entry>
 434      </row>
 435
 436      <row>
 437       <entry><literal>attribute_udt_name</literal></entry>
 438       <entry><type>sql_identifier</type></entry>
 439       <entry>
 440        Name of the attribute data type
 441       </entry>
 442      </row>
 443
 444      <row>
 445       <entry><literal>scope_catalog</literal></entry>
 446       <entry><type>sql_identifier</type></entry>
 447       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
 448      </row>
 449
 450      <row>
 451       <entry><literal>scope_schema</literal></entry>
 452       <entry><type>sql_identifier</type></entry>
 453       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
 454      </row>
 455
 456      <row>
 457       <entry><literal>scope_name</literal></entry>
 458       <entry><type>sql_identifier</type></entry>
 459       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
 460      </row>
 461
 462      <row>
 463       <entry><literal>maximum_cardinality</literal></entry>
 464       <entry><type>cardinal_number</type></entry>
 465       <entry>Always null, because arrays always have unlimited maximum cardinality in <productname>PostgreSQL</></entry>
 466      </row>
 467
 468      <row>
 469       <entry><literal>dtd_identifier</literal></entry>
 470       <entry><type>sql_identifier</type></entry>
 471       <entry>
 472        An identifier of the data type descriptor of the column, unique
 473        among the data type descriptors pertaining to the table.  This
 474        is mainly useful for joining with other instances of such
 475        identifiers.  (The specific format of the identifier is not
 476        defined and not guaranteed to remain the same in future
 477        versions.)
 478       </entry>
 479      </row>
 480
 481      <row>
 482       <entry><literal>is_derived_reference_attribute</literal></entry>
 483       <entry><type>character_data</type></entry>
 484       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
 485      </row>
 486     </tbody>
 487    </tgroup>
 488   </table>
 489
 490   <para>
 491    See also under <xref linkend="infoschema-columns">, a similarly
 492    structured view, for further information on some of the columns.
 493   </para>
 494  </sect1>
 495
 496  <sect1 id="infoschema-check-constraint-routine-usage">
 497   <title><literal>check_constraint_routine_usage</literal></title>
 498
 499   <para>
 500    The view <literal>check_constraint_routine_usage</literal>
 501    identifies routines (functions and procedures) that are used by a
 502    check constraint.  Only those routines are shown that are owned by
 503    a currently enabled role.
 504   </para>
 505
 506   <table>
 507    <title><literal>check_constraint_routine_usage</literal> Columns</title>
 508
 509    <tgroup cols="3">
 510     <thead>
 511      <row>
 512       <entry>Name</entry>
 513       <entry>Data Type</entry>
 514       <entry>Description</entry>
 515      </row>
 516     </thead>
 517
 518     <tbody>
 519      <row>
 520       <entry><literal>constraint_catalog</literal></entry>
 521       <entry><literal>sql_identifier</literal></entry>
 522       <entry>Name of the database containing the constraint (always the current database)</entry>
 523      </row>
 524
 525      <row>
 526       <entry><literal>constraint_schema</literal></entry>
 527       <entry><literal>sql_identifier</literal></entry>
 528       <entry>Name of the schema containing the constraint</entry>
 529      </row>
 530
 531      <row>
 532       <entry><literal>constraint_name</literal></entry>
 533       <entry><literal>sql_identifier</literal></entry>
 534       <entry>Name of the constraint</entry>
 535      </row>
 536
 537      <row>
 538       <entry><literal>specific_catalog</literal></entry>
 539       <entry><literal>sql_identifier</literal></entry>
 540       <entry>Name of the database containing the function (always the current database)</entry>
 541      </row>
 542
 543      <row>
 544       <entry><literal>specific_schema</literal></entry>
 545       <entry><literal>sql_identifier</literal></entry>
 546       <entry>Name of the schema containing the function</entry>
 547      </row>
 548
 549      <row>
 550       <entry><literal>specific_name</literal></entry>
 551       <entry><literal>sql_identifier</literal></entry>
 552       <entry>
 553        The <quote>specific name</quote> of the function.  See <xref
 554        linkend="infoschema-routines"> for more information.
 555       </entry>
 556      </row>
 557     </tbody>
 558    </tgroup>
 559   </table>
 560  </sect1>
 561
 562  <sect1 id="infoschema-check-constraints">
 563   <title><literal>check_constraints</literal></title>
 564
 565   <para>
 566    The view <literal>check_constraints</literal> contains all check
 567    constraints, either defined on a table or on a domain, that are
 568    owned by a currently enabled role.  (The owner of the table or
 569    domain is the owner of the constraint.)
 570   </para>
 571
 572   <table>
 573    <title><literal>check_constraints</literal> Columns</title>
 574
 575    <tgroup cols="3">
 576     <thead>
 577      <row>
 578       <entry>Name</entry>
 579       <entry>Data Type</entry>
 580       <entry>Description</entry>
 581      </row>
 582     </thead>
 583
 584     <tbody>
 585      <row>
 586       <entry><literal>constraint_catalog</literal></entry>
 587       <entry><literal>sql_identifier</literal></entry>
 588       <entry>Name of the database containing the constraint (always the current database)</entry>
 589      </row>
 590
 591      <row>
 592       <entry><literal>constraint_schema</literal></entry>
 593       <entry><literal>sql_identifier</literal></entry>
 594       <entry>Name of the schema containing the constraint</entry>
 595      </row>
 596
 597      <row>
 598       <entry><literal>constraint_name</literal></entry>
 599       <entry><literal>sql_identifier</literal></entry>
 600       <entry>Name of the constraint</entry>
 601      </row>
 602
 603      <row>
 604       <entry><literal>check_clause</literal></entry>
 605       <entry><literal>character_data</literal></entry>
 606       <entry>The check expression of the check constraint</entry>
 607      </row>
 608     </tbody>
 609    </tgroup>
 610   </table>
 611  </sect1>
 612
 613  <sect1 id="infoschema-column-domain-usage">
 614   <title><literal>column_domain_usage</literal></title>
 615
 616   <para>
 617    The view <literal>column_domain_usage</literal> identifies all
 618    columns (of a table or a view) that make use of some domain defined
 619    in the current database and owned by a currently enabled role.
 620   </para>
 621
 622   <table>
 623    <title><literal>column_domain_usage</literal> Columns</title>
 624
 625    <tgroup cols="3">
 626     <thead>
 627      <row>
 628       <entry>Name</entry>
 629       <entry>Data Type</entry>
 630       <entry>Description</entry>
 631      </row>
 632     </thead>
 633
 634     <tbody>
 635      <row>
 636       <entry><literal>domain_catalog</literal></entry>
 637       <entry><type>sql_identifier</type></entry>
 638       <entry>Name of the database containing the domain (always the current database)</entry>
 639      </row>
 640
 641      <row>
 642       <entry><literal>domain_schema</literal></entry>
 643       <entry><type>sql_identifier</type></entry>
 644       <entry>Name of the schema containing the domain</entry>
 645      </row>
 646
 647      <row>
 648       <entry><literal>domain_name</literal></entry>
 649       <entry><type>sql_identifier</type></entry>
 650       <entry>Name of the domain</entry>
 651      </row>
 652
 653      <row>
 654       <entry><literal>table_catalog</literal></entry>
 655       <entry><type>sql_identifier</type></entry>
 656       <entry>Name of the database containing the table (always the current database)</entry>
 657      </row>
 658
 659      <row>
 660       <entry><literal>table_schema</literal></entry>
 661       <entry><type>sql_identifier</type></entry>
 662       <entry>Name of the schema containing the table</entry>
 663      </row>
 664
 665      <row>
 666       <entry><literal>table_name</literal></entry>
 667       <entry><type>sql_identifier</type></entry>
 668       <entry>Name of the table</entry>
 669      </row>
 670
 671      <row>
 672       <entry><literal>column_name</literal></entry>
 673       <entry><type>sql_identifier</type></entry>
 674       <entry>Name of the column</entry>
 675      </row>
 676     </tbody>
 677    </tgroup>
 678   </table>
 679  </sect1>
 680
 681  <sect1 id="infoschema-column-privileges">
 682   <title><literal>column_privileges</literal></title>
 683
 684   <para>
 685    The view <literal>column_privileges</literal> identifies all
 686    privileges granted on columns to a currently enabled role or by a
 687    currently enabled role.  There is one row for each combination of
 688    column, grantor, and grantee.
 689   </para>
 690
 691   <para>
 692    If a privilege has been granted on an entire table, it will show up in
 693    this view as a grant for each column, but only for the
 694    privilege types where column granularity is possible:
 695    <literal>SELECT</literal>, <literal>INSERT</literal>,
 696    <literal>UPDATE</literal>, <literal>REFERENCES</literal>.
 697   </para>
 698
 699   <table>
 700    <title><literal>column_privileges</literal> Columns</title>
 701
 702    <tgroup cols="3">
 703     <thead>
 704      <row>
 705       <entry>Name</entry>
 706       <entry>Data Type</entry>
 707       <entry>Description</entry>
 708      </row>
 709     </thead>
 710
 711     <tbody>
 712      <row>
 713       <entry><literal>grantor</literal></entry>
 714       <entry><type>sql_identifier</type></entry>
 715       <entry>Name of the role that granted the privilege</entry>
 716      </row>
 717
 718      <row>
 719       <entry><literal>grantee</literal></entry>
 720       <entry><type>sql_identifier</type></entry>
 721       <entry>Name of the role that the privilege was granted to</entry>
 722      </row>
 723
 724      <row>
 725       <entry><literal>table_catalog</literal></entry>
 726       <entry><type>sql_identifier</type></entry>
 727       <entry>Name of the database that contains the table that contains the column (always the current database)</entry>
 728      </row>
 729
 730      <row>
 731       <entry><literal>table_schema</literal></entry>
 732       <entry><type>sql_identifier</type></entry>
 733       <entry>Name of the schema that contains the table that contains the column</entry>
 734      </row>
 735
 736      <row>
 737       <entry><literal>table_name</literal></entry>
 738       <entry><type>sql_identifier</type></entry>
 739       <entry>Name of the table that contains the column</entry>
 740      </row>
 741
 742      <row>
 743       <entry><literal>column_name</literal></entry>
 744       <entry><type>sql_identifier</type></entry>
 745       <entry>Name of the column</entry>
 746      </row>
 747
 748      <row>
 749       <entry><literal>privilege_type</literal></entry>
 750       <entry><type>character_data</type></entry>
 751       <entry>
 752        Type of the privilege: <literal>SELECT</literal>,
 753        <literal>INSERT</literal>, <literal>UPDATE</literal>, or
 754        <literal>REFERENCES</literal>
 755       </entry>
 756      </row>
 757
 758      <row>
 759       <entry><literal>is_grantable</literal></entry>
 760       <entry><type>character_data</type></entry>
 761       <entry><literal>YES</literal> if the privilege is grantable, <literal>NO</literal> if not</entry>
 762      </row>
 763     </tbody>
 764    </tgroup>
 765   </table>
 766  </sect1>
 767
 768  <sect1 id="infoschema-column-udt-usage">
 769   <title><literal>column_udt_usage</literal></title>
 770
 771   <para>
 772    The view <literal>column_udt_usage</literal> identifies all columns
 773    that use data types owned by a currently enabled role.  Note that in
 774    <productname>PostgreSQL</productname>, built-in data types behave
 775    like user-defined types, so they are included here as well.  See
 776    also <xref linkend="infoschema-columns"> for details.
 777   </para>
 778
 779   <table>
 780    <title><literal>column_udt_usage</literal> Columns</title>
 781
 782    <tgroup cols="3">
 783     <thead>
 784      <row>
 785       <entry>Name</entry>
 786       <entry>Data Type</entry>
 787       <entry>Description</entry>
 788      </row>
 789     </thead>
 790
 791     <tbody>
 792      <row>
 793       <entry><literal>udt_catalog</literal></entry>
 794       <entry><type>sql_identifier</type></entry>
 795       <entry>
 796        Name of the database that the column data type (the underlying
 797        type of the domain, if applicable) is defined in (always the
 798        current database)
 799       </entry>
 800      </row>
 801
 802      <row>
 803       <entry><literal>udt_schema</literal></entry>
 804       <entry><type>sql_identifier</type></entry>
 805       <entry>
 806        Name of the schema that the column data type (the underlying
 807        type of the domain, if applicable) is defined in
 808       </entry>
 809      </row>
 810
 811      <row>
 812       <entry><literal>udt_name</literal></entry>
 813       <entry><type>sql_identifier</type></entry>
 814       <entry>
 815        Name of the column data type (the underlying type of the
 816        domain, if applicable)
 817       </entry>
 818      </row>
 819
 820      <row>
 821       <entry><literal>table_catalog</literal></entry>
 822       <entry><type>sql_identifier</type></entry>
 823       <entry>Name of the database containing the table (always the current database)</entry>
 824      </row>
 825
 826      <row>
 827       <entry><literal>table_schema</literal></entry>
 828       <entry><type>sql_identifier</type></entry>
 829       <entry>Name of the schema containing the table</entry>
 830      </row>
 831
 832      <row>
 833       <entry><literal>table_name</literal></entry>
 834       <entry><type>sql_identifier</type></entry>
 835       <entry>Name of the table</entry>
 836      </row>
 837
 838      <row>
 839       <entry><literal>column_name</literal></entry>
 840       <entry><type>sql_identifier</type></entry>
 841       <entry>Name of the column</entry>
 842      </row>
 843     </tbody>
 844    </tgroup>
 845   </table>
 846  </sect1>
 847
 848  <sect1 id="infoschema-columns">
 849   <title><literal>columns</literal></title>
 850
 851   <para>
 852    The view <literal>columns</literal> contains information about all
 853    table columns (or view columns) in the database.  System columns
 854    (<literal>oid</>, etc.) are not included.  Only those columns are
 855    shown that the current user has access to (by way of being the
 856    owner or having some privilege).
 857   </para>
 858
 859   <table>
 860    <title><literal>columns</literal> Columns</title>
 861
 862    <tgroup cols="3">
 863     <thead>
 864      <row>
 865       <entry>Name</entry>
 866       <entry>Data Type</entry>
 867       <entry>Description</entry>
 868      </row>
 869     </thead>
 870
 871     <tbody>
 872      <row>
 873       <entry><literal>table_catalog</literal></entry>
 874       <entry><type>sql_identifier</type></entry>
 875       <entry>Name of the database containing the table (always the current database)</entry>
 876      </row>
 877
 878      <row>
 879       <entry><literal>table_schema</literal></entry>
 880       <entry><type>sql_identifier</type></entry>
 881       <entry>Name of the schema containing the table</entry>
 882      </row>
 883
 884      <row>
 885       <entry><literal>table_name</literal></entry>
 886       <entry><type>sql_identifier</type></entry>
 887       <entry>Name of the table</entry>
 888      </row>
 889
 890      <row>
 891       <entry><literal>column_name</literal></entry>
 892       <entry><type>sql_identifier</type></entry>
 893       <entry>Name of the column</entry>
 894      </row>
 895
 896      <row>
 897       <entry><literal>ordinal_position</literal></entry>
 898       <entry><type>cardinal_number</type></entry>
 899       <entry>Ordinal position of the column within the table (count starts at 1)</entry>
 900      </row>
 901
 902      <row>
 903       <entry><literal>column_default</literal></entry>
 904       <entry><type>character_data</type></entry>
 905       <entry>Default expression of the column</entry>
 906      </row>
 907
 908      <row>
 909       <entry><literal>is_nullable</literal></entry>
 910       <entry><type>character_data</type></entry>
 911       <entry>
 912        <literal>YES</literal> if the column is possibly nullable,
 913        <literal>NO</literal> if it is known not nullable.  A not-null
 914        constraint is one way a column can be known not nullable, but
 915        there can be others.
 916       </entry>
 917      </row>
 918
 919      <row>
 920       <entry><literal>data_type</literal></entry>
 921       <entry><type>character_data</type></entry>
 922       <entry>
 923        Data type of the column, if it is a built-in type, or
 924        <literal>ARRAY</literal> if it is some array (in that case, see
 925        the view <literal>element_types</literal>), else
 926        <literal>USER-DEFINED</literal> (in that case, the type is
 927        identified in <literal>udt_name</literal> and associated
 928        columns).  If the column is based on a domain, this column
 929        refers to the type underlying the domain (and the domain is
 930        identified in <literal>domain_name</literal> and associated
 931        columns).
 932       </entry>
 933      </row>
 934
 935      <row>
 936       <entry><literal>character_maximum_length</literal></entry>
 937       <entry><type>cardinal_number</type></entry>
 938       <entry>
 939        If <literal>data_type</literal> identifies a character or bit
 940        string type, the declared maximum length; null for all other
 941        data types or if no maximum length was declared.
 942       </entry>
 943      </row>
 944
 945      <row>
 946       <entry><literal>character_octet_length</literal></entry>
 947       <entry><type>cardinal_number</type></entry>
 948       <entry>
 949        If <literal>data_type</literal> identifies a character type,
 950        the maximum possible length in octets (bytes) of a datum (this
 951        should not be of concern to <productname>PostgreSQL</productname> users); null for all
 952        other data types.
 953       </entry>
 954      </row>
 955
 956      <row>
 957       <entry><literal>numeric_precision</literal></entry>
 958       <entry><type>cardinal_number</type></entry>
 959       <entry>
 960        If <literal>data_type</literal> identifies a numeric type, this
 961        column contains the (declared or implicit) precision of the
 962        type for this column.  The precision indicates the number of
 963        significant digits.  It can be expressed in decimal (base 10)
 964        or binary (base 2) terms, as specified in the column
 965        <literal>numeric_precision_radix</literal>.  For all other data
 966        types, this column is null.
 967       </entry>
 968      </row>
 969
 970      <row>
 971       <entry><literal>numeric_precision_radix</literal></entry>
 972       <entry><type>cardinal_number</type></entry>
 973       <entry>
 974        If <literal>data_type</literal> identifies a numeric type, this
 975        column indicates in which base the values in the columns
 976        <literal>numeric_precision</literal> and
 977        <literal>numeric_scale</literal> are expressed.  The value is
 978        either 2 or 10.  For all other data types, this column is null.
 979       </entry>
 980      </row>
 981
 982      <row>
 983       <entry><literal>numeric_scale</literal></entry>
 984       <entry><type>cardinal_number</type></entry>
 985       <entry>
 986        If <literal>data_type</literal> identifies an exact numeric
 987        type, this column contains the (declared or implicit) scale of
 988        the type for this column.  The scale indicates the number of
 989        significant digits to the right of the decimal point.  It can
 990        be expressed in decimal (base 10) or binary (base 2) terms, as
 991        specified in the column
 992        <literal>numeric_precision_radix</literal>.  For all other data
 993        types, this column is null.
 994       </entry>
 995      </row>
 996
 997      <row>
 998       <entry><literal>datetime_precision</literal></entry>
 999       <entry><type>cardinal_number</type></entry>
1000       <entry>
1001        If <literal>data_type</literal> identifies a date, time,
1002        timestamp, or interval type, this column contains the (declared
1003        or implicit) fractional seconds precision of the type for this
1004        column, that is, the number of decimal digits maintained
1005        following the decimal point in the seconds value.  For all
1006        other data types, this column is null.
1007       </entry>
1008      </row>
1009
1010      <row>
1011       <entry><literal>interval_type</literal></entry>
1012       <entry><type>character_data</type></entry>
1013       <entry>Not yet implemented</entry>
1014      </row>
1015
1016      <row>
1017       <entry><literal>interval_precision</literal></entry>
1018       <entry><type>character_data</type></entry>
1019       <entry>Not yet implemented</entry>
1020      </row>
1021
1022      <row>
1023       <entry><literal>character_set_catalog</literal></entry>
1024       <entry><type>sql_identifier</type></entry>
1025       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1026      </row>
1027
1028      <row>
1029       <entry><literal>character_set_schema</literal></entry>
1030       <entry><type>sql_identifier</type></entry>
1031       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1032      </row>
1033
1034      <row>
1035       <entry><literal>character_set_name</literal></entry>
1036       <entry><type>sql_identifier</type></entry>
1037       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1038      </row>
1039
1040      <row>
1041       <entry><literal>collation_catalog</literal></entry>
1042       <entry><type>sql_identifier</type></entry>
1043       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1044      </row>
1045
1046      <row>
1047       <entry><literal>collation_schema</literal></entry>
1048       <entry><type>sql_identifier</type></entry>
1049       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1050      </row>
1051
1052      <row>
1053       <entry><literal>collation_name</literal></entry>
1054       <entry><type>sql_identifier</type></entry>
1055       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1056      </row>
1057
1058      <row>
1059       <entry><literal>domain_catalog</literal></entry>
1060       <entry><type>sql_identifier</type></entry>
1061       <entry>
1062        If the column has a domain type, the name of the database that
1063        the domain is defined in (always the current database), else
1064        null.
1065       </entry>
1066      </row>
1067
1068      <row>
1069       <entry><literal>domain_schema</literal></entry>
1070       <entry><type>sql_identifier</type></entry>
1071       <entry>
1072        If the column has a domain type, the name of the schema that
1073        the domain is defined in, else null.
1074       </entry>
1075      </row>
1076
1077      <row>
1078       <entry><literal>domain_name</literal></entry>
1079       <entry><type>sql_identifier</type></entry>
1080       <entry>If the column has a domain type, the name of the domain, else null.</entry>
1081      </row>
1082
1083      <row>
1084       <entry><literal>udt_catalog</literal></entry>
1085       <entry><type>sql_identifier</type></entry>
1086       <entry>
1087        Name of the database that the column data type (the underlying
1088        type of the domain, if applicable) is defined in (always the
1089        current database)
1090       </entry>
1091      </row>
1092
1093      <row>
1094       <entry><literal>udt_schema</literal></entry>
1095       <entry><type>sql_identifier</type></entry>
1096       <entry>
1097        Name of the schema that the column data type (the underlying
1098        type of the domain, if applicable) is defined in
1099       </entry>
1100      </row>
1101
1102      <row>
1103       <entry><literal>udt_name</literal></entry>
1104       <entry><type>sql_identifier</type></entry>
1105       <entry>
1106        Name of the column data type (the underlying type of the
1107        domain, if applicable)
1108       </entry>
1109      </row>
1110
1111      <row>
1112       <entry><literal>scope_catalog</literal></entry>
1113       <entry><type>sql_identifier</type></entry>
1114       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1115      </row>
1116
1117      <row>
1118       <entry><literal>scope_schema</literal></entry>
1119       <entry><type>sql_identifier</type></entry>
1120       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1121      </row>
1122
1123      <row>
1124       <entry><literal>scope_name</literal></entry>
1125       <entry><type>sql_identifier</type></entry>
1126       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1127      </row>
1128
1129      <row>
1130       <entry><literal>maximum_cardinality</literal></entry>
1131       <entry><type>cardinal_number</type></entry>
1132       <entry>Always null, because arrays always have unlimited maximum cardinality in <productname>PostgreSQL</></entry>
1133      </row>
1134
1135      <row>
1136       <entry><literal>dtd_identifier</literal></entry>
1137       <entry><type>sql_identifier</type></entry>
1138       <entry>
1139        An identifier of the data type descriptor of the column, unique
1140        among the data type descriptors pertaining to the table.  This
1141        is mainly useful for joining with other instances of such
1142        identifiers.  (The specific format of the identifier is not
1143        defined and not guaranteed to remain the same in future
1144        versions.)
1145       </entry>
1146      </row>
1147
1148      <row>
1149       <entry><literal>is_self_referencing</literal></entry>
1150       <entry><type>character_data</type></entry>
1151       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1152      </row>
1153
1154      <row>
1155       <entry><literal>is_identity</literal></entry>
1156       <entry><type>character_data</type></entry>
1157       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1158      </row>
1159
1160      <row>
1161       <entry><literal>identity_generation</literal></entry>
1162       <entry><type>character_data</type></entry>
1163       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1164      </row>
1165
1166      <row>
1167       <entry><literal>identity_start</literal></entry>
1168       <entry><type>character_data</type></entry>
1169       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1170      </row>
1171
1172      <row>
1173       <entry><literal>identity_increment</literal></entry>
1174       <entry><type>character_data</type></entry>
1175       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1176      </row>
1177
1178      <row>
1179       <entry><literal>identity_maximum</literal></entry>
1180       <entry><type>character_data</type></entry>
1181       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1182      </row>
1183
1184      <row>
1185       <entry><literal>identity_minimum</literal></entry>
1186       <entry><type>character_data</type></entry>
1187       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1188      </row>
1189
1190      <row>
1191       <entry><literal>identity_cycle</literal></entry>
1192       <entry><type>character_data</type></entry>
1193       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1194      </row>
1195
1196      <row>
1197       <entry><literal>is_generated</literal></entry>
1198       <entry><type>character_data</type></entry>
1199       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1200      </row>
1201
1202      <row>
1203       <entry><literal>generation_expression</literal></entry>
1204       <entry><type>character_data</type></entry>
1205       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1206      </row>
1207
1208      <row>
1209       <entry><literal>is_updatable</literal></entry>
1210       <entry><type>character_data</type></entry>
1211       <entry>
1212        <literal>YES</literal> if the column is updatable,
1213        <literal>NO</literal> if not (Columns in base tables are always
1214        updatable, columns in views not necessarily)
1215       </entry>
1216      </row>
1217     </tbody>
1218    </tgroup>
1219   </table>
1220
1221   <para>
1222    Since data types can be defined in a variety of ways in SQL, and
1223    <productname>PostgreSQL</productname> contains additional ways to
1224    define data types, their representation in the information schema
1225    can be somewhat difficult.  The column <literal>data_type</literal>
1226    is supposed to identify the underlying built-in type of the column.
1227    In <productname>PostgreSQL</productname>, this means that the type
1228    is defined in the system catalog schema
1229    <literal>pg_catalog</literal>.  This column might be useful if the
1230    application can handle the well-known built-in types specially (for
1231    example, format the numeric types differently or use the data in
1232    the precision columns).  The columns <literal>udt_name</literal>,
1233    <literal>udt_schema</literal>, and <literal>udt_catalog</literal>
1234    always identify the underlying data type of the column, even if the
1235    column is based on a domain.  (Since
1236    <productname>PostgreSQL</productname> treats built-in types like
1237    user-defined types, built-in types appear here as well.  This is an
1238    extension of the SQL standard.)  These columns should be used if an
1239    application wants to process data differently according to the
1240    type, because in that case it wouldn't matter if the column is
1241    really based on a domain.  If the column is based on a domain, the
1242    identity of the domain is stored in the columns
1243    <literal>domain_name</literal>, <literal>domain_schema</literal>,
1244    and <literal>domain_catalog</literal>.  If you want to pair up
1245    columns with their associated data types and treat domains as
1246    separate types, you could write <literal>coalesce(domain_name,
1247    udt_name)</literal>, etc.
1248   </para>
1249  </sect1>
1250
1251  <sect1 id="infoschema-constraint-column-usage">
1252   <title><literal>constraint_column_usage</literal></title>
1253
1254   <para>
1255    The view <literal>constraint_column_usage</literal> identifies all
1256    columns in the current database that are used by some constraint.
1257    Only those columns are shown that are contained in a table owned by
1258    a currently enabled role.  For a check constraint, this view
1259    identifies the columns that are used in the check expression.  For
1260    a foreign key constraint, this view identifies the columns that the
1261    foreign key references.  For a unique or primary key constraint,
1262    this view identifies the constrained columns.
1263   </para>
1264
1265   <table>
1266    <title><literal>constraint_column_usage</literal> Columns</title>
1267
1268    <tgroup cols="3">
1269     <thead>
1270      <row>
1271       <entry>Name</entry>
1272       <entry>Data Type</entry>
1273       <entry>Description</entry>
1274      </row>
1275     </thead>
1276
1277     <tbody>
1278      <row>
1279       <entry><literal>table_catalog</literal></entry>
1280       <entry><type>sql_identifier</type></entry>
1281       <entry>
1282        Name of the database that contains the table that contains the
1283        column that is used by some constraint (always the current
1284        database)
1285       </entry>
1286      </row>
1287
1288      <row>
1289       <entry><literal>table_schema</literal></entry>
1290       <entry><type>sql_identifier</type></entry>
1291       <entry>
1292        Name of the schema that contains the table that contains the
1293        column that is used by some constraint
1294       </entry>
1295      </row>
1296
1297      <row>
1298       <entry><literal>table_name</literal></entry>
1299       <entry><type>sql_identifier</type></entry>
1300       <entry>
1301        Name of the table that contains the column that is used by some
1302        constraint
1303       </entry>
1304      </row>
1305
1306      <row>
1307       <entry><literal>column_name</literal></entry>
1308       <entry><type>sql_identifier</type></entry>
1309       <entry>
1310        Name of the column that is used by some constraint
1311       </entry>
1312      </row>
1313
1314      <row>
1315       <entry><literal>constraint_catalog</literal></entry>
1316       <entry><type>sql_identifier</type></entry>
1317       <entry>Name of the database that contains the constraint (always the current database)</entry>
1318      </row>
1319
1320      <row>
1321       <entry><literal>constraint_schema</literal></entry>
1322       <entry><type>sql_identifier</type></entry>
1323       <entry>Name of the schema that contains the constraint</entry>
1324      </row>
1325
1326      <row>
1327       <entry><literal>constraint_name</literal></entry>
1328       <entry><type>sql_identifier</type></entry>
1329       <entry>Name of the constraint</entry>
1330      </row>
1331     </tbody>
1332    </tgroup>
1333   </table>
1334  </sect1>
1335
1336  <sect1 id="infoschema-constraint-table-usage">
1337   <title><literal>constraint_table_usage</literal></title>
1338
1339   <para>
1340    The view <literal>constraint_table_usage</literal> identifies all
1341    tables in the current database that are used by some constraint and
1342    are owned by a currently enabled role.  (This is different from the
1343    view <literal>table_constraints</literal>, which identifies all
1344    table constraints along with the table they are defined on.)  For a
1345    foreign key constraint, this view identifies the table that the
1346    foreign key references.  For a unique or primary key constraint,
1347    this view simply identifies the table the constraint belongs to.
1348    Check constraints and not-null constraints are not included in this
1349    view.
1350   </para>
1351
1352   <table>
1353    <title><literal>constraint_table_usage</literal> Columns</title>
1354
1355    <tgroup cols="3">
1356     <thead>
1357      <row>
1358       <entry>Name</entry>
1359       <entry>Data Type</entry>
1360       <entry>Description</entry>
1361      </row>
1362     </thead>
1363
1364     <tbody>
1365      <row>
1366       <entry><literal>table_catalog</literal></entry>
1367       <entry><type>sql_identifier</type></entry>
1368       <entry>
1369        Name of the database that contains the table that is used by
1370        some constraint (always the current database)
1371       </entry>
1372      </row>
1373
1374      <row>
1375       <entry><literal>table_schema</literal></entry>
1376       <entry><type>sql_identifier</type></entry>
1377       <entry>
1378        Name of the schema that contains the table that is used by some
1379        constraint
1380       </entry>
1381      </row>
1382
1383      <row>
1384       <entry><literal>table_name</literal></entry>
1385       <entry><type>sql_identifier</type></entry>
1386       <entry>Name of the table that is used by some constraint</entry>
1387      </row>
1388
1389      <row>
1390       <entry><literal>constraint_catalog</literal></entry>
1391       <entry><type>sql_identifier</type></entry>
1392       <entry>Name of the database that contains the constraint (always the current database)</entry>
1393      </row>
1394
1395      <row>
1396       <entry><literal>constraint_schema</literal></entry>
1397       <entry><type>sql_identifier</type></entry>
1398       <entry>Name of the schema that contains the constraint</entry>
1399      </row>
1400
1401      <row>
1402       <entry><literal>constraint_name</literal></entry>
1403       <entry><type>sql_identifier</type></entry>
1404       <entry>Name of the constraint</entry>
1405      </row>
1406     </tbody>
1407    </tgroup>
1408   </table>
1409  </sect1>
1410
1411  <sect1 id="infoschema-data-type-privileges">
1412   <title><literal>data_type_privileges</literal></title>
1413
1414   <para>
1415    The view <literal>data_type_privileges</literal> identifies all
1416    data type descriptors that the current user has access to, by way
1417    of being the owner of the described object or having some privilege
1418    for it.  A data type descriptor is generated whenever a data type
1419    is used in the definition of a table column, a domain, or a
1420    function (as parameter or return type) and stores some information
1421    about how the data type is used in that instance (for example, the
1422    declared maximum length, if applicable).  Each data type
1423    descriptor is assigned an arbitrary identifier that is unique
1424    among the data type descriptor identifiers assigned for one object
1425    (table, domain, function).  This view is probably not useful for
1426    applications, but it is used to define some other views in the
1427    information schema.
1428   </para>
1429
1430   <table>
1431    <title><literal>data_type_privileges</literal> Columns</title>
1432
1433    <tgroup cols="3">
1434     <thead>
1435      <row>
1436       <entry>Name</entry>
1437       <entry>Data Type</entry>
1438       <entry>Description</entry>
1439      </row>
1440     </thead>
1441
1442     <tbody>
1443      <row>
1444       <entry><literal>object_catalog</literal></entry>
1445       <entry><type>sql_identifier</type></entry>
1446       <entry>Name of the database that contains the described object (always the current database)</entry>
1447      </row>
1448
1449      <row>
1450       <entry><literal>object_schema</literal></entry>
1451       <entry><type>sql_identifier</type></entry>
1452       <entry>Name of the schema that contains the described object</entry>
1453      </row>
1454
1455      <row>
1456       <entry><literal>object_name</literal></entry>
1457       <entry><type>sql_identifier</type></entry>
1458       <entry>Name of the described object</entry>
1459      </row>
1460
1461      <row>
1462       <entry><literal>object_type</literal></entry>
1463       <entry><type>character_data</type></entry>
1464       <entry>
1465        The type of the described object: one of
1466        <literal>TABLE</literal> (the data type descriptor pertains to
1467        a column of that table), <literal>DOMAIN</literal> (the data
1468        type descriptors pertains to that domain),
1469        <literal>ROUTINE</literal> (the data type descriptor pertains
1470        to a parameter or the return data type of that function).
1471       </entry>
1472      </row>
1473
1474      <row>
1475       <entry><literal>dtd_identifier</literal></entry>
1476       <entry><type>sql_identifier</type></entry>
1477       <entry>
1478        The identifier of the data type descriptor, which is unique
1479        among the data type descriptors for that same object.
1480       </entry>
1481      </row>
1482     </tbody>
1483    </tgroup>
1484   </table>
1485  </sect1>
1486
1487  <sect1 id="infoschema-domain-constraints">
1488   <title><literal>domain_constraints</literal></title>
1489
1490   <para>
1491    The view <literal>domain_constraints</literal> contains all
1492    constraints belonging to domains defined in the current database.
1493   </para>
1494
1495   <table>
1496    <title><literal>domain_constraints</literal> Columns</title>
1497
1498    <tgroup cols="3">
1499     <thead>
1500      <row>
1501       <entry>Name</entry>
1502       <entry>Data Type</entry>
1503       <entry>Description</entry>
1504      </row>
1505     </thead>
1506
1507     <tbody>
1508      <row>
1509       <entry><literal>constraint_catalog</literal></entry>
1510       <entry><type>sql_identifier</type></entry>
1511       <entry>Name of the database that contains the constraint (always the current database)</entry>
1512      </row>
1513
1514      <row>
1515       <entry><literal>constraint_schema</literal></entry>
1516       <entry><type>sql_identifier</type></entry>
1517       <entry>Name of the schema that contains the constraint</entry>
1518      </row>
1519
1520      <row>
1521       <entry><literal>constraint_name</literal></entry>
1522       <entry><type>sql_identifier</type></entry>
1523       <entry>Name of the constraint</entry>
1524      </row>
1525
1526      <row>
1527       <entry><literal>domain_catalog</literal></entry>
1528       <entry><type>sql_identifier</type></entry>
1529       <entry>Name of the database that contains the domain (always the current database)</entry>
1530      </row>
1531
1532      <row>
1533       <entry><literal>domain_schema</literal></entry>
1534       <entry><type>sql_identifier</type></entry>
1535       <entry>Name of the schema that contains the domain</entry>
1536      </row>
1537
1538      <row>
1539       <entry><literal>domain_name</literal></entry>
1540       <entry><type>sql_identifier</type></entry>
1541       <entry>Name of the domain</entry>
1542      </row>
1543
1544      <row>
1545       <entry><literal>is_deferrable</literal></entry>
1546       <entry><type>character_data</type></entry>
1547       <entry><literal>YES</literal> if the constraint is deferrable, <literal>NO</literal> if not</entry>
1548      </row>
1549
1550      <row>
1551       <entry><literal>initially_deferred</literal></entry>
1552       <entry><type>character_data</type></entry>
1553       <entry><literal>YES</literal> if the constraint is deferrable and initially deferred, <literal>NO</literal> if not</entry>
1554      </row>
1555     </tbody>
1556    </tgroup>
1557   </table>
1558  </sect1>
1559
1560  <sect1 id="infoschema-domain-udt-usage">
1561   <title><literal>domain_udt_usage</literal></title>
1562
1563   <para>
1564    The view <literal>domain_udt_usage</literal> identifies all domains
1565    that are based on data types owned by a currently enabled role.
1566    Note that in <productname>PostgreSQL</productname>, built-in data
1567    types behave like user-defined types, so they are included here as
1568    well.
1569   </para>
1570
1571   <table>
1572    <title><literal>domain_udt_usage</literal> Columns</title>
1573
1574    <tgroup cols="3">
1575     <thead>
1576      <row>
1577       <entry>Name</entry>
1578       <entry>Data Type</entry>
1579       <entry>Description</entry>
1580      </row>
1581     </thead>
1582
1583     <tbody>
1584      <row>
1585       <entry><literal>udt_catalog</literal></entry>
1586       <entry><type>sql_identifier</type></entry>
1587       <entry>Name of the database that the domain data type is defined in (always the current database)</entry>
1588      </row>
1589
1590      <row>
1591       <entry><literal>udt_schema</literal></entry>
1592       <entry><type>sql_identifier</type></entry>
1593       <entry>Name of the schema that the domain data type is defined in</entry>
1594      </row>
1595
1596      <row>
1597       <entry><literal>udt_name</literal></entry>
1598       <entry><type>sql_identifier</type></entry>
1599       <entry>Name of the domain data type</entry>
1600      </row>
1601
1602      <row>
1603       <entry><literal>domain_catalog</literal></entry>
1604       <entry><type>sql_identifier</type></entry>
1605       <entry>Name of the database that contains the domain (always the current database)</entry>
1606      </row>
1607
1608      <row>
1609       <entry><literal>domain_schema</literal></entry>
1610       <entry><type>sql_identifier</type></entry>
1611       <entry>Name of the schema that contains the domain</entry>
1612      </row>
1613
1614      <row>
1615       <entry><literal>domain_name</literal></entry>
1616       <entry><type>sql_identifier</type></entry>
1617       <entry>Name of the domain</entry>
1618      </row>
1619     </tbody>
1620    </tgroup>
1621   </table>
1622  </sect1>
1623
1624  <sect1 id="infoschema-domains">
1625   <title><literal>domains</literal></title>
1626
1627   <para>
1628    The view <literal>domains</literal> contains all domains defined in
1629    the current database.
1630   </para>
1631
1632   <table>
1633    <title><literal>domains</literal> Columns</title>
1634
1635    <tgroup cols="3">
1636     <thead>
1637      <row>
1638       <entry>Name</entry>
1639       <entry>Data Type</entry>
1640       <entry>Description</entry>
1641      </row>
1642     </thead>
1643
1644     <tbody>
1645      <row>
1646       <entry><literal>domain_catalog</literal></entry>
1647       <entry><type>sql_identifier</type></entry>
1648       <entry>Name of the database that contains the domain (always the current database)</entry>
1649      </row>
1650
1651      <row>
1652       <entry><literal>domain_schema</literal></entry>
1653       <entry><type>sql_identifier</type></entry>
1654       <entry>Name of the schema that contains the domain</entry>
1655      </row>
1656
1657      <row>
1658       <entry><literal>domain_name</literal></entry>
1659       <entry><type>sql_identifier</type></entry>
1660       <entry>Name of the domain</entry>
1661      </row>
1662
1663      <row>
1664       <entry><literal>data_type</literal></entry>
1665       <entry><type>character_data</type></entry>
1666       <entry>
1667        Data type of the domain, if it is a built-in type, or
1668        <literal>ARRAY</literal> if it is some array (in that case, see
1669        the view <literal>element_types</literal>), else
1670        <literal>USER-DEFINED</literal> (in that case, the type is
1671        identified in <literal>udt_name</literal> and associated
1672        columns).
1673       </entry>
1674      </row>
1675
1676      <row>
1677       <entry><literal>character_maximum_length</literal></entry>
1678       <entry><type>cardinal_number</type></entry>
1679       <entry>
1680        If the domain has a character or bit string type, the declared
1681        maximum length; null for all other data types or if no maximum
1682        length was declared.
1683       </entry>
1684      </row>
1685
1686      <row>
1687       <entry><literal>character_octet_length</literal></entry>
1688       <entry><type>cardinal_number</type></entry>
1689       <entry>
1690        If the domain has a character type, the maximum possible length
1691        in octets (bytes) of a datum (this should not be of concern to
1692        <productname>PostgreSQL</productname> users); null for all
1693        other data types.
1694       </entry>
1695      </row>
1696
1697      <row>
1698       <entry><literal>character_set_catalog</literal></entry>
1699       <entry><type>sql_identifier</type></entry>
1700       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1701      </row>
1702
1703      <row>
1704       <entry><literal>character_set_schema</literal></entry>
1705       <entry><type>sql_identifier</type></entry>
1706       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1707      </row>
1708
1709      <row>
1710       <entry><literal>character_set_name</literal></entry>
1711       <entry><type>sql_identifier</type></entry>
1712       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1713      </row>
1714
1715      <row>
1716       <entry><literal>collation_catalog</literal></entry>
1717       <entry><type>sql_identifier</type></entry>
1718       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1719      </row>
1720
1721      <row>
1722       <entry><literal>collation_schema</literal></entry>
1723       <entry><type>sql_identifier</type></entry>
1724       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1725      </row>
1726
1727      <row>
1728       <entry><literal>collation_name</literal></entry>
1729       <entry><type>sql_identifier</type></entry>
1730       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1731      </row>
1732
1733      <row>
1734       <entry><literal>numeric_precision</literal></entry>
1735       <entry><type>cardinal_number</type></entry>
1736       <entry>
1737        If the domain has a numeric type, this column contains the
1738        (declared or implicit) precision of the type for this domain.
1739        The precision indicates the number of significant digits.  It
1740        can be expressed in decimal (base 10) or binary (base 2) terms,
1741        as specified in the column
1742        <literal>numeric_precision_radix</literal>.  For all other data
1743        types, this column is null.
1744       </entry>
1745      </row>
1746
1747      <row>
1748       <entry><literal>numeric_precision_radix</literal></entry>
1749       <entry><type>cardinal_number</type></entry>
1750       <entry>
1751        If the domain has a numeric type, this column indicates in
1752        which base the values in the columns
1753        <literal>numeric_precision</literal> and
1754        <literal>numeric_scale</literal> are expressed.  The value is
1755        either 2 or 10.  For all other data types, this column is null.
1756       </entry>
1757      </row>
1758
1759      <row>
1760       <entry><literal>numeric_scale</literal></entry>
1761       <entry><type>cardinal_number</type></entry>
1762       <entry>
1763        If the domain has an exact numeric type, this column contains
1764        the (declared or implicit) scale of the type for this domain.
1765        The scale indicates the number of significant digits to the
1766        right of the decimal point.  It can be expressed in decimal
1767        (base 10) or binary (base 2) terms, as specified in the column
1768        <literal>numeric_precision_radix</literal>.  For all other data
1769        types, this column is null.
1770       </entry>
1771      </row>
1772
1773      <row>
1774       <entry><literal>datetime_precision</literal></entry>
1775       <entry><type>cardinal_number</type></entry>
1776       <entry>
1777        If <literal>data_type</literal> identifies a date, time,
1778        timestamp, or interval type, this column contains the (declared
1779        or implicit) fractional seconds precision of the type for this
1780        domain, that is, the number of decimal digits maintained
1781        following the decimal point in the seconds value.  For all
1782        other data types, this column is null.
1783       </entry>
1784      </row>
1785
1786      <row>
1787       <entry><literal>interval_type</literal></entry>
1788       <entry><type>character_data</type></entry>
1789       <entry>Not yet implemented</entry>
1790      </row>
1791
1792      <row>
1793       <entry><literal>interval_precision</literal></entry>
1794       <entry><type>character_data</type></entry>
1795       <entry>Not yet implemented</entry>
1796      </row>
1797
1798      <row>
1799       <entry><literal>domain_default</literal></entry>
1800       <entry><type>character_data</type></entry>
1801       <entry>Default expression of the domain</entry>
1802      </row>
1803
1804      <row>
1805       <entry><literal>udt_catalog</literal></entry>
1806       <entry><type>sql_identifier</type></entry>
1807       <entry>Name of the database that the domain data type is defined in (always the current database)</entry>
1808      </row>
1809
1810      <row>
1811       <entry><literal>udt_schema</literal></entry>
1812       <entry><type>sql_identifier</type></entry>
1813       <entry>Name of the schema that the domain data type is defined in</entry>
1814      </row>
1815
1816      <row>
1817       <entry><literal>udt_name</literal></entry>
1818       <entry><type>sql_identifier</type></entry>
1819       <entry>Name of the domain data type</entry>
1820      </row>
1821
1822      <row>
1823       <entry><literal>scope_catalog</literal></entry>
1824       <entry><type>sql_identifier</type></entry>
1825       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1826      </row>
1827
1828      <row>
1829       <entry><literal>scope_schema</literal></entry>
1830       <entry><type>sql_identifier</type></entry>
1831       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1832      </row>
1833
1834      <row>
1835       <entry><literal>scope_name</literal></entry>
1836       <entry><type>sql_identifier</type></entry>
1837       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1838      </row>
1839
1840      <row>
1841       <entry><literal>maximum_cardinality</literal></entry>
1842       <entry><type>cardinal_number</type></entry>
1843       <entry>Always null, because arrays always have unlimited maximum cardinality in <productname>PostgreSQL</></entry>
1844      </row>
1845
1846      <row>
1847       <entry><literal>dtd_identifier</literal></entry>
1848       <entry><type>sql_identifier</type></entry>
1849       <entry>
1850        An identifier of the data type descriptor of the domain, unique
1851        among the data type descriptors pertaining to the domain (which
1852        is trivial, because a domain only contains one data type
1853        descriptor).  This is mainly useful for joining with other
1854        instances of such identifiers.  (The specific format of the
1855        identifier is not defined and not guaranteed to remain the same
1856        in future versions.)
1857       </entry>
1858      </row>
1859     </tbody>
1860    </tgroup>
1861   </table>
1862  </sect1>
1863
1864  <sect1 id="infoschema-element-types">
1865   <title><literal>element_types</literal></title>
1866
1867   <para>
1868    The view <literal>element_types</literal> contains the data type
1869    descriptors of the elements of arrays.  When a table column,
1870    domain, function parameter, or function return value is defined to
1871    be of an array type, the respective information schema view only
1872    contains <literal>ARRAY</literal> in the column
1873    <literal>data_type</literal>.  To obtain information on the element
1874    type of the array, you can join the respective view with this view.
1875    For example, to show the columns of a table with data types and
1876    array element types, if applicable, you could do:
1877 <programlisting>
1878 SELECT c.column_name, c.data_type, e.data_type AS element_type
1879 FROM information_schema.columns c LEFT JOIN information_schema.element_types e
1880      ON ((c.table_catalog, c.table_schema, c.table_name, 'TABLE', c.dtd_identifier)
1881        = (e.object_catalog, e.object_schema, e.object_name, e.object_type, e.dtd_identifier))
1882 WHERE c.table_schema = '...' AND c.table_name = '...'
1883 ORDER BY c.ordinal_position;
1884 </programlisting>
1885    This view only includes objects that the current user has access
1886    to, by way of being the owner or having some privilege.
1887   </para>
1888
1889   <table>
1890    <title><literal>element_types</literal> Columns</title>
1891
1892    <tgroup cols="3">
1893     <thead>
1894      <row>
1895       <entry>Name</entry>
1896       <entry>Data Type</entry>
1897       <entry>Description</entry>
1898      </row>
1899     </thead>
1900
1901     <tbody>
1902      <row>
1903       <entry><literal>object_catalog</literal></entry>
1904       <entry><type>sql_identifier</type></entry>
1905       <entry>
1906        Name of the database that contains the object that uses the
1907        array being described (always the current database)
1908       </entry>
1909      </row>
1910
1911      <row>
1912       <entry><literal>object_schema</literal></entry>
1913       <entry><type>sql_identifier</type></entry>
1914       <entry>
1915        Name of the schema that contains the object that uses the array
1916        being described
1917       </entry>
1918      </row>
1919
1920      <row>
1921       <entry><literal>object_name</literal></entry>
1922       <entry><type>sql_identifier</type></entry>
1923       <entry>
1924        Name of the object that uses the array being described
1925       </entry>
1926      </row>
1927
1928      <row>
1929       <entry><literal>object_type</literal></entry>
1930       <entry><type>character_data</type></entry>
1931       <entry>
1932        The type of the object that uses the array being described: one
1933        of <literal>TABLE</literal> (the array is used by a column of
1934        that table), <literal>DOMAIN</literal> (the array is used by
1935        that domain), <literal>ROUTINE</literal> (the array is used by
1936        a parameter or the return data type of that function).
1937       </entry>
1938      </row>
1939
1940      <row>
1941       <entry><literal>dtd_identifier</literal></entry>
1942       <entry><type>sql_identifier</type></entry>
1943       <entry>
1944        The identifier of the data type descriptor of the array being
1945        described
1946       </entry>
1947      </row>
1948
1949      <row>
1950       <entry><literal>data_type</literal></entry>
1951       <entry><type>character_data</type></entry>
1952       <entry>
1953        Data type of the array elements, if it is a built-in type, else
1954        <literal>USER-DEFINED</literal> (in that case, the type is
1955        identified in <literal>udt_name</literal> and associated
1956        columns).
1957       </entry>
1958      </row>
1959
1960      <row>
1961       <entry><literal>character_maximum_length</literal></entry>
1962       <entry><type>cardinal_number</type></entry>
1963       <entry>Always null, since this information is not applied to array element data types in <productname>PostgreSQL</></entry>
1964      </row>
1965
1966      <row>
1967       <entry><literal>character_octet_length</literal></entry>
1968       <entry><type>cardinal_number</type></entry>
1969       <entry>Always null, since this information is not applied to array element data types in <productname>PostgreSQL</></entry>
1970      </row>
1971
1972      <row>
1973       <entry><literal>character_set_catalog</literal></entry>
1974       <entry><type>sql_identifier</type></entry>
1975       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1976      </row>
1977
1978      <row>
1979       <entry><literal>character_set_schema</literal></entry>
1980       <entry><type>sql_identifier</type></entry>
1981       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1982      </row>
1983
1984      <row>
1985       <entry><literal>character_set_name</literal></entry>
1986       <entry><type>sql_identifier</type></entry>
1987       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1988      </row>
1989
1990      <row>
1991       <entry><literal>collation_catalog</literal></entry>
1992       <entry><type>sql_identifier</type></entry>
1993       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
1994      </row>
1995
1996      <row>
1997       <entry><literal>collation_schema</literal></entry>
1998       <entry><type>sql_identifier</type></entry>
1999       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2000      </row>
2001
2002      <row>
2003       <entry><literal>collation_name</literal></entry>
2004       <entry><type>sql_identifier</type></entry>
2005       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2006      </row>
2007
2008      <row>
2009       <entry><literal>numeric_precision</literal></entry>
2010       <entry><type>cardinal_number</type></entry>
2011       <entry>Always null, since this information is not applied to array element data types in <productname>PostgreSQL</></entry>
2012      </row>
2013
2014      <row>
2015       <entry><literal>numeric_precision_radix</literal></entry>
2016       <entry><type>cardinal_number</type></entry>
2017       <entry>Always null, since this information is not applied to array element data types in <productname>PostgreSQL</></entry>
2018      </row>
2019
2020      <row>
2021       <entry><literal>numeric_scale</literal></entry>
2022       <entry><type>cardinal_number</type></entry>
2023       <entry>Always null, since this information is not applied to array element data types in <productname>PostgreSQL</></entry>
2024      </row>
2025
2026      <row>
2027       <entry><literal>datetime_precision</literal></entry>
2028       <entry><type>cardinal_number</type></entry>
2029       <entry>Always null, since this information is not applied to array element data types in <productname>PostgreSQL</></entry>
2030      </row>
2031
2032      <row>
2033       <entry><literal>interval_type</literal></entry>
2034       <entry><type>character_data</type></entry>
2035       <entry>Always null, since this information is not applied to array element data types in <productname>PostgreSQL</></entry>
2036      </row>
2037
2038      <row>
2039       <entry><literal>interval_precision</literal></entry>
2040       <entry><type>character_data</type></entry>
2041       <entry>Always null, since this information is not applied to array element data types in <productname>PostgreSQL</></entry>
2042      </row>
2043
2044      <row>
2045       <entry><literal>domain_default</literal></entry>
2046       <entry><type>character_data</type></entry>
2047       <entry>Not yet implemented</entry>
2048      </row>
2049
2050      <row>
2051       <entry><literal>udt_catalog</literal></entry>
2052       <entry><type>sql_identifier</type></entry>
2053       <entry>
2054        Name of the database that the data type of the elements is
2055        defined in (always the current database)
2056       </entry>
2057      </row>
2058
2059      <row>
2060       <entry><literal>udt_schema</literal></entry>
2061       <entry><type>sql_identifier</type></entry>
2062       <entry>
2063        Name of the schema that the data type of the elements is
2064        defined in
2065       </entry>
2066      </row>
2067
2068      <row>
2069       <entry><literal>udt_name</literal></entry>
2070       <entry><type>sql_identifier</type></entry>
2071       <entry>
2072        Name of the data type of the elements
2073       </entry>
2074      </row>
2075
2076      <row>
2077       <entry><literal>scope_catalog</literal></entry>
2078       <entry><type>sql_identifier</type></entry>
2079       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2080      </row>
2081
2082      <row>
2083       <entry><literal>scope_schema</literal></entry>
2084       <entry><type>sql_identifier</type></entry>
2085       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2086      </row>
2087
2088      <row>
2089       <entry><literal>scope_name</literal></entry>
2090       <entry><type>sql_identifier</type></entry>
2091       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2092      </row>
2093
2094      <row>
2095       <entry><literal>maximum_cardinality</literal></entry>
2096       <entry><type>cardinal_number</type></entry>
2097       <entry>Always null, because arrays always have unlimited maximum cardinality in <productname>PostgreSQL</></entry>
2098      </row>
2099
2100     </tbody>
2101    </tgroup>
2102   </table>
2103  </sect1>
2104
2105  <sect1 id="infoschema-enabled-roles">
2106   <title><literal>enabled_roles</literal></title>
2107
2108   <para>
2109    The view <literal>enabled_roles</literal> identifies the currently
2110    <quote>enabled roles</quote>.  The enabled roles are recursively
2111    defined as the current user together with all roles that have been
2112    granted to the enabled roles with automatic inheritance.  In other
2113    words, these are all roles that the current user has direct or
2114    indirect, automatically inheriting membership in.
2115    <indexterm><primary>enabled role</primary></indexterm>
2116    <indexterm><primary>role</primary><secondary>enabled</secondary></indexterm>
2117   </para>
2118
2119   <para>
2120    For permission checking, the set of <quote>applicable roles</quote>
2121    is applied, which can be broader than the set of enabled roles.  So
2122    generally, it is better to use the view
2123    <literal>applicable_roles</literal> instead of this one; see also
2124    there.
2125   </para>
2126
2127   <table>
2128    <title><literal>enabled_roles</literal> Columns</title>
2129
2130    <tgroup cols="3">
2131     <thead>
2132      <row>
2133       <entry>Name</entry>
2134       <entry>Data Type</entry>
2135       <entry>Description</entry>
2136      </row>
2137     </thead>
2138
2139     <tbody>
2140      <row>
2141       <entry><literal>role_name</literal></entry>
2142       <entry><type>sql_identifier</type></entry>
2143       <entry>Name of a role</entry>
2144      </row>
2145     </tbody>
2146    </tgroup>
2147   </table>
2148  </sect1>
2149
2150  <sect1 id="infoschema-foreign-data-wrapper-options">
2151   <title><literal>foreign_data_wrapper_options</literal></title>
2152
2153   <para>
2154    The view <literal>foreign_data_wrapper_options</literal> contains
2155    all the options defined for foreign-data wrappers in the current
2156    database.  Only those foreign-data wrappers are shown that the
2157    current user has access to (by way of being the owner or having
2158    some privilege).
2159   </para>
2160
2161   <table>
2162    <title><literal>foreign_data_wrapper_options</literal> Columns</title>
2163
2164    <tgroup cols="3">
2165     <thead>
2166      <row>
2167       <entry>Name</entry>
2168       <entry>Data Type</entry>
2169       <entry>Description</entry>
2170      </row>
2171     </thead>
2172
2173     <tbody>
2174      <row>
2175       <entry><literal>foreign_data_wrapper_catalog</literal></entry>
2176       <entry><type>sql_identifier</type></entry>
2177       <entry>Name of the database that the foreign-data wrapper is defined in (always the current database)</entry>
2178      </row>
2179
2180      <row>
2181       <entry><literal>foreign_data_wrapper_name</literal></entry>
2182       <entry><type>sql_identifier</type></entry>
2183       <entry>Name of the foreign-data wrapper</entry>
2184      </row>
2185
2186      <row>
2187       <entry><literal>option_name</literal></entry>
2188       <entry><type>sql_identifier</type></entry>
2189       <entry>Name of an option</entry>
2190      </row>
2191
2192      <row>
2193       <entry><literal>option_value</literal></entry>
2194       <entry><type>character_data</type></entry>
2195       <entry>Value of the option</entry>
2196      </row>
2197     </tbody>
2198    </tgroup>
2199   </table>
2200  </sect1>
2201
2202  <sect1 id="infoschema-foreign-data-wrappers">
2203   <title><literal>foreign_data_wrappers</literal></title>
2204
2205   <para>
2206    The view <literal>foreign_data_wrappers</literal> contains all
2207    foreign-data wrappers defined in the current database.  Only those
2208    foreign-data wrappers are shown that the current user has access to
2209    (by way of being the owner or having some privilege).
2210   </para>
2211
2212   <table>
2213    <title><literal>foreign_data_wrappers</literal> Columns</title>
2214
2215    <tgroup cols="3">
2216     <thead>
2217      <row>
2218       <entry>Name</entry>
2219       <entry>Data Type</entry>
2220       <entry>Description</entry>
2221      </row>
2222     </thead>
2223
2224     <tbody>
2225      <row>
2226       <entry><literal>foreign_data_wrapper_catalog</literal></entry>
2227       <entry><type>sql_identifier</type></entry>
2228       <entry>Name of the database that contains the foreign-data
2229       wrapper (always the current database)</entry>
2230      </row>
2231
2232      <row>
2233       <entry><literal>foreign_data_wrapper_name</literal></entry>
2234       <entry><type>sql_identifier</type></entry>
2235       <entry>Name of the foreign-data wrapper</entry>
2236      </row>
2237
2238      <row>
2239       <entry><literal>authorization_identifier</literal></entry>
2240       <entry><type>sql_identifier</type></entry>
2241       <entry>Name of the owner of the foreign server</entry>
2242      </row>
2243
2244      <row>
2245       <entry><literal>library_name</literal></entry>
2246       <entry><type>character_data</type></entry>
2247       <entry>File name of the library that implementing this foreign-data wrapper</entry>
2248      </row>
2249
2250      <row>
2251       <entry><literal>foreign_data_wrapper_language</literal></entry>
2252       <entry><type>character_data</type></entry>
2253       <entry>Language used to implement this foreign-data wrapper</entry>
2254      </row>
2255     </tbody>
2256    </tgroup>
2257   </table>
2258  </sect1>
2259
2260  <sect1 id="infoschema-foreign-server-options">
2261   <title><literal>foreign_server_options</literal></title>
2262
2263   <para>
2264    The view <literal>foreign_server_options</literal> contains all the
2265    options defined for foreign servers in the current database.  Only
2266    those foreign servers are shown that the current user has access to
2267    (by way of being the owner or having some privilege).
2268   </para>
2269
2270   <table>
2271    <title><literal>foreign_server_options</literal> Columns</title>
2272
2273    <tgroup cols="3">
2274     <thead>
2275      <row>
2276       <entry>Name</entry>
2277       <entry>Data Type</entry>
2278       <entry>Description</entry>
2279      </row>
2280     </thead>
2281
2282     <tbody>
2283      <row>
2284       <entry><literal>foreign_server_catalog</literal></entry>
2285       <entry><type>sql_identifier</type></entry>
2286       <entry>Name of the database that the foreign server is defined in (always the current database)</entry>
2287      </row>
2288
2289      <row>
2290       <entry><literal>foreign_server_name</literal></entry>
2291       <entry><type>sql_identifier</type></entry>
2292       <entry>Name of the foreign server</entry>
2293      </row>
2294
2295      <row>
2296       <entry><literal>option_name</literal></entry>
2297       <entry><type>sql_identifier</type></entry>
2298       <entry>Name of an option</entry>
2299      </row>
2300
2301      <row>
2302       <entry><literal>option_value</literal></entry>
2303       <entry><type>character_data</type></entry>
2304       <entry>Value of the option</entry>
2305      </row>
2306     </tbody>
2307    </tgroup>
2308   </table>
2309  </sect1>
2310
2311  <sect1 id="infoschema-foreign-servers">
2312   <title><literal>foreign_servers</literal></title>
2313
2314   <para>
2315    The view <literal>foreign_servers</literal> contains all foreign
2316    servers defined in the current database.  Only those foreign
2317    servers are shown that the current user has access to (by way of
2318    being the owner or having some privilege).
2319   </para>
2320
2321   <table>
2322    <title><literal>foreign_servers</literal> Columns</title>
2323
2324    <tgroup cols="3">
2325     <thead>
2326      <row>
2327       <entry>Name</entry>
2328       <entry>Data Type</entry>
2329       <entry>Description</entry>
2330      </row>
2331     </thead>
2332
2333     <tbody>
2334      <row>
2335       <entry><literal>foreign_server_catalog</literal></entry>
2336       <entry><type>sql_identifier</type></entry>
2337       <entry>Name of the database that the foreign server is defined in (always the current database)</entry>
2338      </row>
2339
2340      <row>
2341       <entry><literal>foreign_server_name</literal></entry>
2342       <entry><type>sql_identifier</type></entry>
2343       <entry>Name of the foreign server</entry>
2344      </row>
2345
2346      <row>
2347       <entry><literal>foreign_data_wrapper_catalog</literal></entry>
2348       <entry><type>sql_identifier</type></entry>
2349       <entry>Name of the database that contains the foreign-data
2350       wrapper used by the foreign server (always the current database)</entry>
2351      </row>
2352
2353      <row>
2354       <entry><literal>foreign_data_wrapper_name</literal></entry>
2355       <entry><type>sql_identifier</type></entry>
2356       <entry>Name of the foreign-data wrapper used by the foreign server</entry>
2357      </row>
2358
2359      <row>
2360       <entry><literal>foreign_server_type</literal></entry>
2361       <entry><type>character_data</type></entry>
2362       <entry>Foreign server type information, if specified upon creation</entry>
2363      </row>
2364
2365      <row>
2366       <entry><literal>foreign_server_version</literal></entry>
2367       <entry><type>character_data</type></entry>
2368       <entry>Foreign server version information, if specified upon creation</entry>
2369      </row>
2370
2371      <row>
2372       <entry><literal>authorization_identifier</literal></entry>
2373       <entry><type>sql_identifier</type></entry>
2374       <entry>Name of the owner of the foreign server</entry>
2375      </row>
2376     </tbody>
2377    </tgroup>
2378   </table>
2379  </sect1>
2380
2381  <sect1 id="infoschema-key-column-usage">
2382   <title><literal>key_column_usage</literal></title>
2383
2384   <para>
2385    The view <literal>key_column_usage</literal> identifies all columns
2386    in the current database that are restricted by some unique, primary
2387    key, or foreign key constraint.  Check constraints are not included
2388    in this view.  Only those columns are shown that the current user
2389    has access to, by way of being the owner or having some privilege.
2390   </para>
2391
2392   <table>
2393    <title><literal>key_column_usage</literal> Columns</title>
2394
2395    <tgroup cols="3">
2396     <thead>
2397      <row>
2398       <entry>Name</entry>
2399       <entry>Data Type</entry>
2400       <entry>Description</entry>
2401      </row>
2402     </thead>
2403
2404     <tbody>
2405      <row>
2406       <entry><literal>constraint_catalog</literal></entry>
2407       <entry><type>sql_identifier</type></entry>
2408       <entry>Name of the database that contains the constraint (always the current database)</entry>
2409      </row>
2410
2411      <row>
2412       <entry><literal>constraint_schema</literal></entry>
2413       <entry><type>sql_identifier</type></entry>
2414       <entry>Name of the schema that contains the constraint</entry>
2415      </row>
2416
2417      <row>
2418       <entry><literal>constraint_name</literal></entry>
2419       <entry><type>sql_identifier</type></entry>
2420       <entry>Name of the constraint</entry>
2421      </row>
2422
2423      <row>
2424       <entry><literal>table_catalog</literal></entry>
2425       <entry><type>sql_identifier</type></entry>
2426       <entry>
2427        Name of the database that contains the table that contains the
2428        column that is restricted by this constraint (always the
2429        current database)
2430       </entry>
2431      </row>
2432
2433      <row>
2434       <entry><literal>table_schema</literal></entry>
2435       <entry><type>sql_identifier</type></entry>
2436       <entry>
2437        Name of the schema that contains the table that contains the
2438        column that is restricted by this constraint
2439       </entry>
2440      </row>
2441
2442      <row>
2443       <entry><literal>table_name</literal></entry>
2444       <entry><type>sql_identifier</type></entry>
2445       <entry>
2446        Name of the table that contains the column that is restricted
2447        by this constraint
2448       </entry>
2449      </row>
2450
2451      <row>
2452       <entry><literal>column_name</literal></entry>
2453       <entry><type>sql_identifier</type></entry>
2454       <entry>
2455        Name of the column that is restricted by this constraint
2456       </entry>
2457      </row>
2458
2459      <row>
2460       <entry><literal>ordinal_position</literal></entry>
2461       <entry><type>cardinal_number</type></entry>
2462       <entry>
2463        Ordinal position of the column within the constraint key (count
2464        starts at 1)
2465       </entry>
2466      </row>
2467
2468      <row>
2469       <entry><literal>position_in_unique_constraint</literal></entry>
2470       <entry><type>cardinal_number</type></entry>
2471       <entry>
2472        For a foreign-key constraint, ordinal position of the referenced
2473        column within its unique constraint (count starts at 1);
2474        otherwise null
2475       </entry>
2476      </row>
2477     </tbody>
2478    </tgroup>
2479   </table>
2480  </sect1>
2481
2482  <sect1 id="infoschema-parameters">
2483   <title><literal>parameters</literal></title>
2484
2485   <para>
2486    The view <literal>parameters</literal> contains information about
2487    the parameters (arguments) of all functions in the current database.
2488    Only those functions are shown that the current user has access to
2489    (by way of being the owner or having some privilege).
2490   </para>
2491
2492   <table>
2493    <title><literal>parameters</literal> Columns</title>
2494
2495    <tgroup cols="3">
2496     <thead>
2497      <row>
2498       <entry>Name</entry>
2499       <entry>Data Type</entry>
2500       <entry>Description</entry>
2501      </row>
2502     </thead>
2503
2504     <tbody>
2505      <row>
2506       <entry><literal>specific_catalog</literal></entry>
2507       <entry><type>sql_identifier</type></entry>
2508       <entry>Name of the database containing the function (always the current database)</entry>
2509      </row>
2510
2511      <row>
2512       <entry><literal>specific_schema</literal></entry>
2513       <entry><type>sql_identifier</type></entry>
2514       <entry>Name of the schema containing the function</entry>
2515      </row>
2516
2517      <row>
2518       <entry><literal>specific_name</literal></entry>
2519       <entry><type>sql_identifier</type></entry>
2520       <entry>
2521        The <quote>specific name</quote> of the function.  See <xref
2522        linkend="infoschema-routines"> for more information.
2523       </entry>
2524      </row>
2525
2526      <row>
2527       <entry><literal>ordinal_position</literal></entry>
2528       <entry><type>cardinal_number</type></entry>
2529       <entry>
2530        Ordinal position of the parameter in the argument list of the
2531        function (count starts at 1)
2532       </entry>
2533      </row>
2534
2535      <row>
2536       <entry><literal>parameter_mode</literal></entry>
2537       <entry><type>character_data</type></entry>
2538       <entry>
2539        <literal>IN</literal> for input parameter,
2540        <literal>OUT</literal> for output parameter,
2541        and <literal>INOUT</literal> for input/output parameter.
2542       </entry>
2543      </row>
2544
2545      <row>
2546       <entry><literal>is_result</literal></entry>
2547       <entry><type>character_data</type></entry>
2548       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2549      </row>
2550
2551      <row>
2552       <entry><literal>as_locator</literal></entry>
2553       <entry><type>character_data</type></entry>
2554       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2555      </row>
2556
2557      <row>
2558       <entry><literal>parameter_name</literal></entry>
2559       <entry><type>sql_identifier</type></entry>
2560       <entry>Name of the parameter, or null if the parameter has no name</entry>
2561      </row>
2562
2563      <row>
2564       <entry><literal>data_type</literal></entry>
2565       <entry><type>character_data</type></entry>
2566       <entry>
2567        Data type of the parameter, if it is a built-in type, or
2568        <literal>ARRAY</literal> if it is some array (in that case, see
2569        the view <literal>element_types</literal>), else
2570        <literal>USER-DEFINED</literal> (in that case, the type is
2571        identified in <literal>udt_name</literal> and associated
2572        columns).
2573       </entry>
2574      </row>
2575
2576      <row>
2577       <entry><literal>character_maximum_length</literal></entry>
2578       <entry><type>cardinal_number</type></entry>
2579       <entry>Always null, since this information is not applied to parameter data types in <productname>PostgreSQL</></entry>
2580      </row>
2581
2582      <row>
2583       <entry><literal>character_octet_length</literal></entry>
2584       <entry><type>cardinal_number</type></entry>
2585       <entry>Always null, since this information is not applied to parameter data types in <productname>PostgreSQL</></entry>
2586      </row>
2587
2588      <row>
2589       <entry><literal>character_set_catalog</literal></entry>
2590       <entry><type>sql_identifier</type></entry>
2591       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2592      </row>
2593
2594      <row>
2595       <entry><literal>character_set_schema</literal></entry>
2596       <entry><type>sql_identifier</type></entry>
2597       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2598      </row>
2599
2600      <row>
2601       <entry><literal>character_set_name</literal></entry>
2602       <entry><type>sql_identifier</type></entry>
2603       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2604      </row>
2605
2606      <row>
2607       <entry><literal>collation_catalog</literal></entry>
2608       <entry><type>sql_identifier</type></entry>
2609       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2610      </row>
2611
2612      <row>
2613       <entry><literal>collation_schema</literal></entry>
2614       <entry><type>sql_identifier</type></entry>
2615       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2616      </row>
2617
2618      <row>
2619       <entry><literal>collation_name</literal></entry>
2620       <entry><type>sql_identifier</type></entry>
2621       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2622      </row>
2623
2624      <row>
2625       <entry><literal>numeric_precision</literal></entry>
2626       <entry><type>cardinal_number</type></entry>
2627       <entry>Always null, since this information is not applied to parameter data types in <productname>PostgreSQL</></entry>
2628      </row>
2629
2630      <row>
2631       <entry><literal>numeric_precision_radix</literal></entry>
2632       <entry><type>cardinal_number</type></entry>
2633       <entry>Always null, since this information is not applied to parameter data types in <productname>PostgreSQL</></entry>
2634      </row>
2635
2636      <row>
2637       <entry><literal>numeric_scale</literal></entry>
2638       <entry><type>cardinal_number</type></entry>
2639       <entry>Always null, since this information is not applied to parameter data types in <productname>PostgreSQL</></entry>
2640      </row>
2641
2642      <row>
2643       <entry><literal>datetime_precision</literal></entry>
2644       <entry><type>cardinal_number</type></entry>
2645       <entry>Always null, since this information is not applied to parameter data types in <productname>PostgreSQL</></entry>
2646      </row>
2647
2648      <row>
2649       <entry><literal>interval_type</literal></entry>
2650       <entry><type>character_data</type></entry>
2651       <entry>Always null, since this information is not applied to parameter data types in <productname>PostgreSQL</></entry>
2652      </row>
2653
2654      <row>
2655       <entry><literal>interval_precision</literal></entry>
2656       <entry><type>character_data</type></entry>
2657       <entry>Always null, since this information is not applied to parameter data types in <productname>PostgreSQL</></entry>
2658      </row>
2659
2660      <row>
2661       <entry><literal>udt_catalog</literal></entry>
2662       <entry><type>sql_identifier</type></entry>
2663       <entry>
2664        Name of the database that the data type of the parameter is
2665        defined in (always the current database)
2666       </entry>
2667      </row>
2668
2669      <row>
2670       <entry><literal>udt_schema</literal></entry>
2671       <entry><type>sql_identifier</type></entry>
2672       <entry>
2673        Name of the schema that the data type of the parameter is
2674        defined in
2675       </entry>
2676      </row>
2677
2678      <row>
2679       <entry><literal>udt_name</literal></entry>
2680       <entry><type>sql_identifier</type></entry>
2681       <entry>
2682        Name of the data type of the parameter
2683       </entry>
2684      </row>
2685
2686      <row>
2687       <entry><literal>scope_catalog</literal></entry>
2688       <entry><type>sql_identifier</type></entry>
2689       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2690      </row>
2691
2692      <row>
2693       <entry><literal>scope_schema</literal></entry>
2694       <entry><type>sql_identifier</type></entry>
2695       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2696      </row>
2697
2698      <row>
2699       <entry><literal>scope_name</literal></entry>
2700       <entry><type>sql_identifier</type></entry>
2701       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
2702      </row>
2703
2704      <row>
2705       <entry><literal>maximum_cardinality</literal></entry>
2706       <entry><type>cardinal_number</type></entry>
2707       <entry>Always null, because arrays always have unlimited maximum cardinality in <productname>PostgreSQL</></entry>
2708      </row>
2709
2710      <row>
2711       <entry><literal>dtd_identifier</literal></entry>
2712       <entry><type>sql_identifier</type></entry>
2713       <entry>
2714        An identifier of the data type descriptor of the parameter,
2715        unique among the data type descriptors pertaining to the
2716        function.  This is mainly useful for joining with other
2717        instances of such identifiers.  (The specific format of the
2718        identifier is not defined and not guaranteed to remain the same
2719        in future versions.)
2720       </entry>
2721      </row>
2722     </tbody>
2723    </tgroup>
2724   </table>
2725  </sect1>
2726
2727  <sect1 id="infoschema-referential-constraints">
2728   <title><literal>referential_constraints</literal></title>
2729
2730   <para>
2731    The view <literal>referential_constraints</literal> contains all
2732    referential (foreign key) constraints in the current database.
2733    Only those constraints are shown for which the current user has
2734    write access to the referencing table (by way of being the
2735    owner or having some privilege other than SELECT).
2736   </para>
2737
2738   <table>
2739    <title><literal>referential_constraints</literal> Columns</title>
2740
2741    <tgroup cols="3">
2742     <thead>
2743      <row>
2744       <entry>Name</entry>
2745       <entry>Data Type</entry>
2746       <entry>Description</entry>
2747      </row>
2748     </thead>
2749
2750     <tbody>
2751      <row>
2752       <entry><literal>constraint_catalog</literal></entry>
2753       <entry><literal>sql_identifier</literal></entry>
2754       <entry>Name of the database containing the constraint (always the current database)</entry>
2755      </row>
2756
2757      <row>
2758       <entry><literal>constraint_schema</literal></entry>
2759       <entry><literal>sql_identifier</literal></entry>
2760       <entry>Name of the schema containing the constraint</entry>
2761      </row>
2762
2763      <row>
2764       <entry><literal>constraint_name</literal></entry>
2765       <entry><literal>sql_identifier</literal></entry>
2766       <entry>Name of the constraint</entry>
2767      </row>
2768
2769      <row>
2770       <entry><literal>unique_constraint_catalog</literal></entry>
2771       <entry><literal>sql_identifier</literal></entry>
2772       <entry>
2773        Name of the database that contains the unique or primary key
2774        constraint that the foreign key constraint references (always
2775        the current database)
2776       </entry>
2777      </row>
2778
2779      <row>
2780       <entry><literal>unique_constraint_schema</literal></entry>
2781       <entry><literal>sql_identifier</literal></entry>
2782       <entry>
2783        Name of the schema that contains the unique or primary key
2784        constraint that the foreign key constraint references
2785       </entry>
2786      </row>
2787
2788      <row>
2789       <entry><literal>unique_constraint_name</literal></entry>
2790       <entry><literal>sql_identifier</literal></entry>
2791       <entry>
2792        Name of the unique or primary key constraint that the foreign
2793        key constraint references
2794       </entry>
2795      </row>
2796
2797      <row>
2798       <entry><literal>match_option</literal></entry>
2799       <entry><literal>character_data</literal></entry>
2800       <entry>
2801        Match option of the foreign key constraint:
2802        <literal>FULL</literal>, <literal>PARTIAL</literal>, or
2803        <literal>NONE</literal>.
2804       </entry>
2805      </row>
2806
2807      <row>
2808       <entry><literal>update_rule</literal></entry>
2809       <entry><literal>character_data</literal></entry>
2810       <entry>
2811        Update rule of the foreign key constraint:
2812        <literal>CASCADE</literal>, <literal>SET NULL</literal>,
2813        <literal>SET DEFAULT</literal>, <literal>RESTRICT</literal>, or
2814        <literal>NO ACTION</literal>.
2815       </entry>
2816      </row>
2817
2818      <row>
2819       <entry><literal>delete_rule</literal></entry>
2820       <entry><literal>character_data</literal></entry>
2821       <entry>
2822        Delete rule of the foreign key constraint:
2823        <literal>CASCADE</literal>, <literal>SET NULL</literal>,
2824        <literal>SET DEFAULT</literal>, <literal>RESTRICT</literal>, or
2825        <literal>NO ACTION</literal>.
2826       </entry>
2827      </row>
2828     </tbody>
2829    </tgroup>
2830   </table>
2831  </sect1>
2832
2833  <sect1 id="infoschema-role-column-grants">
2834   <title><literal>role_column_grants</literal></title>
2835
2836   <para>
2837    The view <literal>role_column_grants</literal> identifies all
2838    privileges granted on columns where the grantor or grantee is a
2839    currently enabled role.  Further information can be found under
2840    <literal>column_privileges</literal>.
2841   </para>
2842
2843   <table>
2844    <title><literal>role_column_grants</literal> Columns</title>
2845
2846    <tgroup cols="3">
2847     <thead>
2848      <row>
2849       <entry>Name</entry>
2850       <entry>Data Type</entry>
2851       <entry>Description</entry>
2852      </row>
2853     </thead>
2854
2855     <tbody>
2856      <row>
2857       <entry><literal>grantor</literal></entry>
2858       <entry><type>sql_identifier</type></entry>
2859       <entry>Name of the role that granted the privilege</entry>
2860      </row>
2861
2862      <row>
2863       <entry><literal>grantee</literal></entry>
2864       <entry><type>sql_identifier</type></entry>
2865       <entry>Name of the role that the privilege was granted to</entry>
2866      </row>
2867
2868      <row>
2869       <entry><literal>table_catalog</literal></entry>
2870       <entry><type>sql_identifier</type></entry>
2871       <entry>Name of the database that contains the table that contains the column (always the current database)</entry>
2872      </row>
2873
2874      <row>
2875       <entry><literal>table_schema</literal></entry>
2876       <entry><type>sql_identifier</type></entry>
2877       <entry>Name of the schema that contains the table that contains the column</entry>
2878      </row>
2879
2880      <row>
2881       <entry><literal>table_name</literal></entry>
2882       <entry><type>sql_identifier</type></entry>
2883       <entry>Name of the table that contains the column</entry>
2884      </row>
2885
2886      <row>
2887       <entry><literal>column_name</literal></entry>
2888       <entry><type>sql_identifier</type></entry>
2889       <entry>Name of the column</entry>
2890      </row>
2891
2892      <row>
2893       <entry><literal>privilege_type</literal></entry>
2894       <entry><type>character_data</type></entry>
2895       <entry>
2896        Type of the privilege: <literal>SELECT</literal>,
2897        <literal>INSERT</literal>, <literal>UPDATE</literal>, or
2898        <literal>REFERENCES</literal>
2899       </entry>
2900      </row>
2901
2902      <row>
2903       <entry><literal>is_grantable</literal></entry>
2904       <entry><type>character_data</type></entry>
2905       <entry><literal>YES</literal> if the privilege is grantable, <literal>NO</literal> if not</entry>
2906      </row>
2907     </tbody>
2908    </tgroup>
2909   </table>
2910  </sect1>
2911
2912  <sect1 id="infoschema-role-routine-grants">
2913   <title><literal>role_routine_grants</literal></title>
2914
2915   <para>
2916    The view <literal>role_routine_grants</literal> identifies all
2917    privileges granted on functions where the grantor or grantee is a
2918    currently enabled role.  Further information can be found under
2919    <literal>routine_privileges</literal>.
2920   </para>
2921
2922   <table>
2923    <title><literal>role_routine_grants</literal> Columns</title>
2924
2925    <tgroup cols="3">
2926     <thead>
2927      <row>
2928       <entry>Name</entry>
2929       <entry>Data Type</entry>
2930       <entry>Description</entry>
2931      </row>
2932     </thead>
2933
2934     <tbody>
2935      <row>
2936       <entry><literal>grantor</literal></entry>
2937       <entry><type>sql_identifier</type></entry>
2938       <entry>Name of the role that granted the privilege</entry>
2939      </row>
2940
2941      <row>
2942       <entry><literal>grantee</literal></entry>
2943       <entry><type>sql_identifier</type></entry>
2944       <entry>Name of the role that the privilege was granted to</entry>
2945      </row>
2946
2947      <row>
2948       <entry><literal>specific_catalog</literal></entry>
2949       <entry><type>sql_identifier</type></entry>
2950       <entry>Name of the database containing the function (always the current database)</entry>
2951      </row>
2952
2953      <row>
2954       <entry><literal>specific_schema</literal></entry>
2955       <entry><type>sql_identifier</type></entry>
2956       <entry>Name of the schema containing the function</entry>
2957      </row>
2958
2959      <row>
2960       <entry><literal>specific_name</literal></entry>
2961       <entry><type>sql_identifier</type></entry>
2962       <entry>
2963        The <quote>specific name</quote> of the function.  See <xref
2964        linkend="infoschema-routines"> for more information.
2965       </entry>
2966      </row>
2967
2968      <row>
2969       <entry><literal>routine_catalog</literal></entry>
2970       <entry><type>sql_identifier</type></entry>
2971       <entry>Name of the database containing the function (always the current database)</entry>
2972      </row>
2973
2974      <row>
2975       <entry><literal>routine_schema</literal></entry>
2976       <entry><type>sql_identifier</type></entry>
2977       <entry>Name of the schema containing the function</entry>
2978      </row>
2979
2980      <row>
2981       <entry><literal>routine_name</literal></entry>
2982       <entry><type>sql_identifier</type></entry>
2983       <entry>Name of the function (might be duplicated in case of overloading)</entry>
2984      </row>
2985
2986      <row>
2987       <entry><literal>privilege_type</literal></entry>
2988       <entry><type>character_data</type></entry>
2989       <entry>Always <literal>EXECUTE</literal> (the only privilege type for functions)</entry>
2990      </row>
2991
2992      <row>
2993       <entry><literal>is_grantable</literal></entry>
2994       <entry><type>character_data</type></entry>
2995       <entry><literal>YES</literal> if the privilege is grantable, <literal>NO</literal> if not</entry>
2996      </row>
2997     </tbody>
2998    </tgroup>
2999   </table>
3000  </sect1>
3001
3002  <sect1 id="infoschema-role-table-grants">
3003   <title><literal>role_table_grants</literal></title>
3004
3005   <para>
3006    The view <literal>role_table_grants</literal> identifies all
3007    privileges granted on tables or views where the grantor or grantee
3008    is a currently enabled role.  Further information can be found
3009    under <literal>table_privileges</literal>.
3010   </para>
3011
3012   <table>
3013    <title><literal>role_table_grants</literal> Columns</title>
3014
3015    <tgroup cols="3">
3016     <thead>
3017      <row>
3018       <entry>Name</entry>
3019       <entry>Data Type</entry>
3020       <entry>Description</entry>
3021      </row>
3022     </thead>
3023
3024     <tbody>
3025      <row>
3026       <entry><literal>grantor</literal></entry>
3027       <entry><type>sql_identifier</type></entry>
3028       <entry>Name of the role that granted the privilege</entry>
3029      </row>
3030
3031      <row>
3032       <entry><literal>grantee</literal></entry>
3033       <entry><type>sql_identifier</type></entry>
3034       <entry>Name of the role that the privilege was granted to</entry>
3035      </row>
3036
3037      <row>
3038       <entry><literal>table_catalog</literal></entry>
3039       <entry><type>sql_identifier</type></entry>
3040       <entry>Name of the database that contains the table (always the current database)</entry>
3041      </row>
3042
3043      <row>
3044       <entry><literal>table_schema</literal></entry>
3045       <entry><type>sql_identifier</type></entry>
3046       <entry>Name of the schema that contains the table</entry>
3047      </row>
3048
3049      <row>
3050       <entry><literal>table_name</literal></entry>
3051       <entry><type>sql_identifier</type></entry>
3052       <entry>Name of the table</entry>
3053      </row>
3054
3055      <row>
3056       <entry><literal>privilege_type</literal></entry>
3057       <entry><type>character_data</type></entry>
3058       <entry>
3059        Type of the privilege: <literal>SELECT</literal>,
3060        <literal>INSERT</literal>, <literal>UPDATE</literal>,
3061        <literal>DELETE</literal>, <literal>TRUNCATE</literal>,
3062        <literal>REFERENCES</literal>, or <literal>TRIGGER</literal>
3063       </entry>
3064      </row>
3065
3066      <row>
3067       <entry><literal>is_grantable</literal></entry>
3068       <entry><type>character_data</type></entry>
3069       <entry><literal>YES</literal> if the privilege is grantable, <literal>NO</literal> if not</entry>
3070      </row>
3071
3072      <row>
3073       <entry><literal>with_hierarchy</literal></entry>
3074       <entry><type>character_data</type></entry>
3075       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3076      </row>
3077     </tbody>
3078    </tgroup>
3079   </table>
3080  </sect1>
3081
3082  <sect1 id="infoschema-role-usage-grants">
3083   <title><literal>role_usage_grants</literal></title>
3084
3085   <para>
3086    The view <literal>role_usage_grants</literal> identifies
3087    <literal>USAGE</literal> privileges granted on various kinds of
3088    objects where the grantor or grantee is a currently enabled role.
3089    Further information can be found under
3090    <literal>usage_privileges</literal>.
3091   </para>
3092
3093   <table>
3094    <title><literal>role_usage_grants</literal> Columns</title>
3095
3096    <tgroup cols="3">
3097     <thead>
3098      <row>
3099       <entry>Name</entry>
3100       <entry>Data Type</entry>
3101       <entry>Description</entry>
3102      </row>
3103     </thead>
3104
3105     <tbody>
3106      <row>
3107       <entry><literal>grantor</literal></entry>
3108       <entry><type>sql_identifier</type></entry>
3109       <entry>The name of the role that granted the privilege</entry>
3110      </row>
3111
3112      <row>
3113       <entry><literal>grantee</literal></entry>
3114       <entry><type>sql_identifier</type></entry>
3115       <entry>The name of the role that the privilege was granted to</entry>
3116      </row>
3117
3118      <row>
3119       <entry><literal>object_catalog</literal></entry>
3120       <entry><type>sql_identifier</type></entry>
3121       <entry>Name of the database containing the object (always the current database)</entry>
3122      </row>
3123
3124      <row>
3125       <entry><literal>object_schema</literal></entry>
3126       <entry><type>sql_identifier</type></entry>
3127       <entry>Name of the schema containing the object, if applicable,
3128       else an empty string</entry>
3129      </row>
3130
3131      <row>
3132       <entry><literal>object_name</literal></entry>
3133       <entry><type>sql_identifier</type></entry>
3134       <entry>Name of the object</entry>
3135      </row>
3136
3137      <row>
3138       <entry><literal>object_type</literal></entry>
3139       <entry><type>character_data</type></entry>
3140       <entry><literal>DOMAIN</literal> or <literal>FOREIGN DATA WRAPPER</literal> or <literal>FOREIGN SERVER</literal></entry>
3141      </row>
3142
3143      <row>
3144       <entry><literal>privilege_type</literal></entry>
3145       <entry><type>character_data</type></entry>
3146       <entry>Always <literal>USAGE</literal></entry>
3147      </row>
3148
3149      <row>
3150       <entry><literal>is_grantable</literal></entry>
3151       <entry><type>character_data</type></entry>
3152       <entry><literal>YES</literal> if the privilege is grantable, <literal>NO</literal> if not</entry>
3153      </row>
3154     </tbody>
3155    </tgroup>
3156   </table>
3157  </sect1>
3158
3159  <sect1 id="infoschema-routine-privileges">
3160   <title><literal>routine_privileges</literal></title>
3161
3162   <para>
3163    The view <literal>routine_privileges</literal> identifies all
3164    privileges granted on functions to a currently enabled role or by a
3165    currently enabled role.  There is one row for each combination of function,
3166    grantor, and grantee.
3167   </para>
3168
3169   <table>
3170    <title><literal>routine_privileges</literal> Columns</title>
3171
3172    <tgroup cols="3">
3173     <thead>
3174      <row>
3175       <entry>Name</entry>
3176       <entry>Data Type</entry>
3177       <entry>Description</entry>
3178      </row>
3179     </thead>
3180
3181     <tbody>
3182      <row>
3183       <entry><literal>grantor</literal></entry>
3184       <entry><type>sql_identifier</type></entry>
3185       <entry>Name of the role that granted the privilege</entry>
3186      </row>
3187
3188      <row>
3189       <entry><literal>grantee</literal></entry>
3190       <entry><type>sql_identifier</type></entry>
3191       <entry>Name of the role that the privilege was granted to</entry>
3192      </row>
3193
3194      <row>
3195       <entry><literal>specific_catalog</literal></entry>
3196       <entry><type>sql_identifier</type></entry>
3197       <entry>Name of the database containing the function (always the current database)</entry>
3198      </row>
3199
3200      <row>
3201       <entry><literal>specific_schema</literal></entry>
3202       <entry><type>sql_identifier</type></entry>
3203       <entry>Name of the schema containing the function</entry>
3204      </row>
3205
3206      <row>
3207       <entry><literal>specific_name</literal></entry>
3208       <entry><type>sql_identifier</type></entry>
3209       <entry>
3210        The <quote>specific name</quote> of the function.  See <xref
3211        linkend="infoschema-routines"> for more information.
3212       </entry>
3213      </row>
3214
3215      <row>
3216       <entry><literal>routine_catalog</literal></entry>
3217       <entry><type>sql_identifier</type></entry>
3218       <entry>Name of the database containing the function (always the current database)</entry>
3219      </row>
3220
3221      <row>
3222       <entry><literal>routine_schema</literal></entry>
3223       <entry><type>sql_identifier</type></entry>
3224       <entry>Name of the schema containing the function</entry>
3225      </row>
3226
3227      <row>
3228       <entry><literal>routine_name</literal></entry>
3229       <entry><type>sql_identifier</type></entry>
3230       <entry>Name of the function (might be duplicated in case of overloading)</entry>
3231      </row>
3232
3233      <row>
3234       <entry><literal>privilege_type</literal></entry>
3235       <entry><type>character_data</type></entry>
3236       <entry>Always <literal>EXECUTE</literal> (the only privilege type for functions)</entry>
3237      </row>
3238
3239      <row>
3240       <entry><literal>is_grantable</literal></entry>
3241       <entry><type>character_data</type></entry>
3242       <entry><literal>YES</literal> if the privilege is grantable, <literal>NO</literal> if not</entry>
3243      </row>
3244     </tbody>
3245    </tgroup>
3246   </table>
3247  </sect1>
3248
3249  <sect1 id="infoschema-routines">
3250   <title><literal>routines</literal></title>
3251
3252   <para>
3253    The view <literal>routines</literal> contains all functions in the
3254    current database.  Only those functions are shown that the current
3255    user has access to (by way of being the owner or having some
3256    privilege).
3257   </para>
3258
3259   <table>
3260    <title><literal>routines</literal> Columns</title>
3261
3262    <tgroup cols="3">
3263     <thead>
3264      <row>
3265       <entry>Name</entry>
3266       <entry>Data Type</entry>
3267       <entry>Description</entry>
3268      </row>
3269     </thead>
3270
3271     <tbody>
3272      <row>
3273       <entry><literal>specific_catalog</literal></entry>
3274       <entry><type>sql_identifier</type></entry>
3275       <entry>Name of the database containing the function (always the current database)</entry>
3276      </row>
3277
3278      <row>
3279       <entry><literal>specific_schema</literal></entry>
3280       <entry><type>sql_identifier</type></entry>
3281       <entry>Name of the schema containing the function</entry>
3282      </row>
3283
3284      <row>
3285       <entry><literal>specific_name</literal></entry>
3286       <entry><type>sql_identifier</type></entry>
3287       <entry>
3288        The <quote>specific name</quote> of the function.  This is a
3289        name that uniquely identifies the function in the schema, even
3290        if the real name of the function is overloaded.  The format of
3291        the specific name is not defined, it should only be used to
3292        compare it to other instances of specific routine names.
3293       </entry>
3294      </row>
3295
3296      <row>
3297       <entry><literal>routine_catalog</literal></entry>
3298       <entry><type>sql_identifier</type></entry>
3299       <entry>Name of the database containing the function (always the current database)</entry>
3300      </row>
3301
3302      <row>
3303       <entry><literal>routine_schema</literal></entry>
3304       <entry><type>sql_identifier</type></entry>
3305       <entry>Name of the schema containing the function</entry>
3306      </row>
3307
3308      <row>
3309       <entry><literal>routine_name</literal></entry>
3310       <entry><type>sql_identifier</type></entry>
3311       <entry>Name of the function (might be duplicated in case of overloading)</entry>
3312      </row>
3313
3314      <row>
3315       <entry><literal>routine_type</literal></entry>
3316       <entry><type>character_data</type></entry>
3317       <entry>
3318        Always <literal>FUNCTION</literal> (In the future there might
3319        be other types of routines.)
3320       </entry>
3321      </row>
3322
3323      <row>
3324       <entry><literal>module_catalog</literal></entry>
3325       <entry><type>sql_identifier</type></entry>
3326       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3327      </row>
3328
3329      <row>
3330       <entry><literal>module_schema</literal></entry>
3331       <entry><type>sql_identifier</type></entry>
3332       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3333      </row>
3334
3335      <row>
3336       <entry><literal>module_name</literal></entry>
3337       <entry><type>sql_identifier</type></entry>
3338       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3339      </row>
3340
3341      <row>
3342       <entry><literal>udt_catalog</literal></entry>
3343       <entry><type>sql_identifier</type></entry>
3344       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3345      </row>
3346
3347      <row>
3348       <entry><literal>udt_schema</literal></entry>
3349       <entry><type>sql_identifier</type></entry>
3350       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3351      </row>
3352
3353      <row>
3354       <entry><literal>udt_name</literal></entry>
3355       <entry><type>sql_identifier</type></entry>
3356       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3357      </row>
3358
3359      <row>
3360       <entry><literal>data_type</literal></entry>
3361       <entry><type>character_data</type></entry>
3362       <entry>
3363        Return data type of the function, if it is a built-in type, or
3364        <literal>ARRAY</literal> if it is some array (in that case, see
3365        the view <literal>element_types</literal>), else
3366        <literal>USER-DEFINED</literal> (in that case, the type is
3367        identified in <literal>type_udt_name</literal> and associated
3368        columns).
3369       </entry>
3370      </row>
3371
3372      <row>
3373       <entry><literal>character_maximum_length</literal></entry>
3374       <entry><type>cardinal_number</type></entry>
3375       <entry>Always null, since this information is not applied to return data types in <productname>PostgreSQL</></entry>
3376      </row>
3377
3378      <row>
3379       <entry><literal>character_octet_length</literal></entry>
3380       <entry><type>cardinal_number</type></entry>
3381       <entry>Always null, since this information is not applied to return data types in <productname>PostgreSQL</></entry>
3382      </row>
3383
3384      <row>
3385       <entry><literal>character_set_catalog</literal></entry>
3386       <entry><type>sql_identifier</type></entry>
3387       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3388      </row>
3389
3390      <row>
3391       <entry><literal>character_set_schema</literal></entry>
3392       <entry><type>sql_identifier</type></entry>
3393       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3394      </row>
3395
3396      <row>
3397       <entry><literal>character_set_name</literal></entry>
3398       <entry><type>sql_identifier</type></entry>
3399       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3400      </row>
3401
3402      <row>
3403       <entry><literal>collation_catalog</literal></entry>
3404       <entry><type>sql_identifier</type></entry>
3405       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3406      </row>
3407
3408      <row>
3409       <entry><literal>collation_schema</literal></entry>
3410       <entry><type>sql_identifier</type></entry>
3411       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3412      </row>
3413
3414      <row>
3415       <entry><literal>collation_name</literal></entry>
3416       <entry><type>sql_identifier</type></entry>
3417       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3418      </row>
3419
3420      <row>
3421       <entry><literal>numeric_precision</literal></entry>
3422       <entry><type>cardinal_number</type></entry>
3423       <entry>Always null, since this information is not applied to return data types in <productname>PostgreSQL</></entry>
3424      </row>
3425
3426      <row>
3427       <entry><literal>numeric_precision_radix</literal></entry>
3428       <entry><type>cardinal_number</type></entry>
3429       <entry>Always null, since this information is not applied to return data types in <productname>PostgreSQL</></entry>
3430      </row>
3431
3432      <row>
3433       <entry><literal>numeric_scale</literal></entry>
3434       <entry><type>cardinal_number</type></entry>
3435       <entry>Always null, since this information is not applied to return data types in <productname>PostgreSQL</></entry>
3436      </row>
3437
3438      <row>
3439       <entry><literal>datetime_precision</literal></entry>
3440       <entry><type>cardinal_number</type></entry>
3441       <entry>Always null, since this information is not applied to return data types in <productname>PostgreSQL</></entry>
3442      </row>
3443
3444      <row>
3445       <entry><literal>interval_type</literal></entry>
3446       <entry><type>character_data</type></entry>
3447       <entry>Always null, since this information is not applied to return data types in <productname>PostgreSQL</></entry>
3448      </row>
3449
3450      <row>
3451       <entry><literal>interval_precision</literal></entry>
3452       <entry><type>character_data</type></entry>
3453       <entry>Always null, since this information is not applied to return data types in <productname>PostgreSQL</></entry>
3454      </row>
3455
3456      <row>
3457       <entry><literal>type_udt_catalog</literal></entry>
3458       <entry><type>sql_identifier</type></entry>
3459       <entry>
3460        Name of the database that the return data type of the function
3461        is defined in (always the current database)
3462       </entry>
3463      </row>
3464
3465      <row>
3466       <entry><literal>type_udt_schema</literal></entry>
3467       <entry><type>sql_identifier</type></entry>
3468       <entry>
3469        Name of the schema that the return data type of the function is
3470        defined in
3471       </entry>
3472      </row>
3473
3474      <row>
3475       <entry><literal>type_udt_name</literal></entry>
3476       <entry><type>sql_identifier</type></entry>
3477       <entry>
3478        Name of the return data type of the function
3479       </entry>
3480      </row>
3481
3482      <row>
3483       <entry><literal>scope_catalog</literal></entry>
3484       <entry><type>sql_identifier</type></entry>
3485       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3486      </row>
3487
3488      <row>
3489       <entry><literal>scope_schema</literal></entry>
3490       <entry><type>sql_identifier</type></entry>
3491       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3492      </row>
3493
3494      <row>
3495       <entry><literal>scope_name</literal></entry>
3496       <entry><type>sql_identifier</type></entry>
3497       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3498      </row>
3499
3500      <row>
3501       <entry><literal>maximum_cardinality</literal></entry>
3502       <entry><type>cardinal_number</type></entry>
3503       <entry>Always null, because arrays always have unlimited maximum cardinality in <productname>PostgreSQL</></entry>
3504      </row>
3505
3506      <row>
3507       <entry><literal>dtd_identifier</literal></entry>
3508       <entry><type>sql_identifier</type></entry>
3509       <entry>
3510        An identifier of the data type descriptor of the return data
3511        type of this function, unique among the data type descriptors
3512        pertaining to the function.  This is mainly useful for joining
3513        with other instances of such identifiers.  (The specific format
3514        of the identifier is not defined and not guaranteed to remain
3515        the same in future versions.)
3516       </entry>
3517      </row>
3518
3519      <row>
3520       <entry><literal>routine_body</literal></entry>
3521       <entry><type>character_data</type></entry>
3522       <entry>
3523        If the function is an SQL function, then
3524        <literal>SQL</literal>, else <literal>EXTERNAL</literal>.
3525       </entry>
3526      </row>
3527
3528      <row>
3529       <entry><literal>routine_definition</literal></entry>
3530       <entry><type>character_data</type></entry>
3531       <entry>
3532        The source text of the function (null if the function is not
3533        owned by a currently enabled role).  (According to the SQL
3534        standard, this column is only applicable if
3535        <literal>routine_body</literal> is <literal>SQL</literal>, but
3536        in <productname>PostgreSQL</productname> it will contain
3537        whatever source text was specified when the function was
3538        created.)
3539       </entry>
3540      </row>
3541
3542      <row>
3543       <entry><literal>external_name</literal></entry>
3544       <entry><type>character_data</type></entry>
3545       <entry>
3546        If this function is a C function, then the external name (link
3547        symbol) of the function; else null.  (This works out to be the
3548        same value that is shown in
3549        <literal>routine_definition</literal>.)
3550       </entry>
3551      </row>
3552
3553      <row>
3554       <entry><literal>external_language</literal></entry>
3555       <entry><type>character_data</type></entry>
3556       <entry>The language the function is written in</entry>
3557      </row>
3558
3559      <row>
3560       <entry><literal>parameter_style</literal></entry>
3561       <entry><type>character_data</type></entry>
3562       <entry>
3563        Always <literal>GENERAL</literal> (The SQL standard defines
3564        other parameter styles, which are not available in <productname>PostgreSQL</>.)
3565       </entry>
3566      </row>
3567
3568      <row>
3569       <entry><literal>is_deterministic</literal></entry>
3570       <entry><type>character_data</type></entry>
3571       <entry>
3572        If the function is declared immutable (called deterministic in
3573        the SQL standard), then <literal>YES</literal>, else
3574        <literal>NO</literal>.  (You cannot query the other volatility
3575        levels available in <productname>PostgreSQL</> through the information schema.)
3576       </entry>
3577      </row>
3578
3579      <row>
3580       <entry><literal>sql_data_access</literal></entry>
3581       <entry><type>character_data</type></entry>
3582       <entry>
3583        Always <literal>MODIFIES</literal>, meaning that the function
3584        possibly modifies SQL data.  This information is not useful for
3585        <productname>PostgreSQL</>.
3586       </entry>
3587      </row>
3588
3589      <row>
3590       <entry><literal>is_null_call</literal></entry>
3591       <entry><type>character_data</type></entry>
3592       <entry>
3593        If the function automatically returns null if any of its
3594        arguments are null, then <literal>YES</literal>, else
3595        <literal>NO</literal>.
3596       </entry>
3597      </row>
3598
3599      <row>
3600       <entry><literal>sql_path</literal></entry>
3601       <entry><type>character_data</type></entry>
3602       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3603      </row>
3604
3605      <row>
3606       <entry><literal>schema_level_routine</literal></entry>
3607       <entry><type>character_data</type></entry>
3608       <entry>
3609        Always <literal>YES</literal> (The opposite would be a method
3610        of a user-defined type, which is a feature not available in
3611        <productname>PostgreSQL</>.)
3612       </entry>
3613      </row>
3614
3615      <row>
3616       <entry><literal>max_dynamic_result_sets</literal></entry>
3617       <entry><type>cardinal_number</type></entry>
3618       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3619      </row>
3620
3621      <row>
3622       <entry><literal>is_user_defined_cast</literal></entry>
3623       <entry><type>character_data</type></entry>
3624       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3625      </row>
3626
3627      <row>
3628       <entry><literal>is_implicitly_invocable</literal></entry>
3629       <entry><type>character_data</type></entry>
3630       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3631      </row>
3632
3633      <row>
3634       <entry><literal>security_type</literal></entry>
3635       <entry><type>character_data</type></entry>
3636       <entry>
3637        If the function runs with the privileges of the current user,
3638        then <literal>INVOKER</literal>, if the function runs with the
3639        privileges of the user who defined it, then
3640        <literal>DEFINER</literal>.
3641       </entry>
3642      </row>
3643
3644      <row>
3645       <entry><literal>to_sql_specific_catalog</literal></entry>
3646       <entry><type>sql_identifier</type></entry>
3647       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3648      </row>
3649
3650      <row>
3651       <entry><literal>to_sql_specific_schema</literal></entry>
3652       <entry><type>sql_identifier</type></entry>
3653       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3654      </row>
3655
3656      <row>
3657       <entry><literal>to_sql_specific_name</literal></entry>
3658       <entry><type>sql_identifier</type></entry>
3659       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3660      </row>
3661
3662      <row>
3663       <entry><literal>as_locator</literal></entry>
3664       <entry><type>character_data</type></entry>
3665       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3666      </row>
3667
3668      <row>
3669       <entry><literal>created</literal></entry>
3670       <entry><type>time_stamp</type></entry>
3671       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3672      </row>
3673
3674      <row>
3675       <entry><literal>last_altered</literal></entry>
3676       <entry><type>time_stamp</type></entry>
3677       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3678      </row>
3679
3680      <row>
3681       <entry><literal>new_savepoint_level</literal></entry>
3682       <entry><type>character_data</type></entry>
3683       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3684      </row>
3685
3686      <row>
3687       <entry><literal>is_udt_dependent</literal></entry>
3688       <entry><type>character_data</type></entry>
3689       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3690      </row>
3691
3692      <row>
3693       <entry><literal>result_cast_from_data_type</literal></entry>
3694       <entry><type>character_data</type></entry>
3695       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3696      </row>
3697
3698      <row>
3699       <entry><literal>result_cast_as_locator</literal></entry>
3700       <entry><type>character_data</type></entry>
3701       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3702      </row>
3703
3704      <row>
3705       <entry><literal>result_cast_char_max_length</literal></entry>
3706       <entry><type>cardinal_number</type></entry>
3707       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3708      </row>
3709
3710      <row>
3711       <entry><literal>result_cast_char_octet_length</literal></entry>
3712       <entry><type>character_data</type></entry>
3713       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3714      </row>
3715
3716      <row>
3717       <entry><literal>result_cast_char_set_catalog</literal></entry>
3718       <entry><type>sql_identifier</type></entry>
3719       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3720      </row>
3721
3722      <row>
3723       <entry><literal>result_cast_char_set_schema</literal></entry>
3724       <entry><type>sql_identifier</type></entry>
3725       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3726      </row>
3727
3728      <row>
3729       <entry><literal>result_cast_char_set_name</literal></entry>
3730       <entry><type>sql_identifier</type></entry>
3731       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3732      </row>
3733
3734      <row>
3735       <entry><literal>result_cast_collation_catalog</literal></entry>
3736       <entry><type>sql_identifier</type></entry>
3737       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3738      </row>
3739
3740      <row>
3741       <entry><literal>result_cast_collation_schema</literal></entry>
3742       <entry><type>sql_identifier</type></entry>
3743       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3744      </row>
3745
3746      <row>
3747       <entry><literal>result_cast_collation_name</literal></entry>
3748       <entry><type>sql_identifier</type></entry>
3749       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3750      </row>
3751
3752      <row>
3753       <entry><literal>result_cast_numeric_precision</literal></entry>
3754       <entry><type>cardinal_number</type></entry>
3755       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3756      </row>
3757
3758      <row>
3759       <entry><literal>result_cast_numeric_precision_radix</literal></entry>
3760       <entry><type>cardinal_number</type></entry>
3761       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3762      </row>
3763
3764      <row>
3765       <entry><literal>result_cast_numeric_scale</literal></entry>
3766       <entry><type>cardinal_number</type></entry>
3767       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3768      </row>
3769
3770      <row>
3771       <entry><literal>result_cast_datetime_precision</literal></entry>
3772       <entry><type>character_data</type></entry>
3773       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3774      </row>
3775
3776      <row>
3777       <entry><literal>result_cast_interval_type</literal></entry>
3778       <entry><type>character_data</type></entry>
3779       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3780      </row>
3781
3782      <row>
3783       <entry><literal>result_cast_interval_precision</literal></entry>
3784       <entry><type>character_data</type></entry>
3785       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3786      </row>
3787
3788      <row>
3789       <entry><literal>result_cast_type_udt_catalog</literal></entry>
3790       <entry><type>sql_identifier</type></entry>
3791       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3792      </row>
3793
3794      <row>
3795       <entry><literal>result_cast_type_udt_schema</literal></entry>
3796       <entry><type>sql_identifier</type></entry>
3797       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3798      </row>
3799
3800      <row>
3801       <entry><literal>result_cast_type_udt_name</literal></entry>
3802       <entry><type>sql_identifier</type></entry>
3803       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3804      </row>
3805
3806      <row>
3807       <entry><literal>result_cast_scope_catalog</literal></entry>
3808       <entry><type>sql_identifier</type></entry>
3809       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3810      </row>
3811
3812      <row>
3813       <entry><literal>result_cast_scope_schema</literal></entry>
3814       <entry><type>sql_identifier</type></entry>
3815       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3816      </row>
3817
3818      <row>
3819       <entry><literal>result_cast_scope_name</literal></entry>
3820       <entry><type>sql_identifier</type></entry>
3821       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3822      </row>
3823
3824      <row>
3825       <entry><literal>result_cast_maximum_cardinality</literal></entry>
3826       <entry><type>cardinal_number</type></entry>
3827       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3828      </row>
3829
3830      <row>
3831       <entry><literal>result_cast_dtd_identifier</literal></entry>
3832       <entry><type>sql_identifier</type></entry>
3833       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3834      </row>
3835     </tbody>
3836    </tgroup>
3837   </table>
3838  </sect1>
3839
3840  <sect1 id="infoschema-schemata">
3841   <title><literal>schemata</literal></title>
3842
3843   <para>
3844    The view <literal>schemata</literal> contains all schemas in the
3845    current database that are owned by a currently enabled role.
3846   </para>
3847
3848   <table>
3849    <title><literal>schemata</literal> Columns</title>
3850
3851    <tgroup cols="3">
3852     <thead>
3853      <row>
3854       <entry>Name</entry>
3855       <entry>Data Type</entry>
3856       <entry>Description</entry>
3857      </row>
3858     </thead>
3859
3860     <tbody>
3861      <row>
3862       <entry><literal>catalog_name</literal></entry>
3863       <entry><type>sql_identifier</type></entry>
3864       <entry>Name of the database that the schema is contained in (always the current database)</entry>
3865      </row>
3866
3867      <row>
3868       <entry><literal>schema_name</literal></entry>
3869       <entry><type>sql_identifier</type></entry>
3870       <entry>Name of the schema</entry>
3871      </row>
3872
3873      <row>
3874       <entry><literal>schema_owner</literal></entry>
3875       <entry><type>sql_identifier</type></entry>
3876       <entry>Name of the owner of the schema</entry>
3877      </row>
3878
3879      <row>
3880       <entry><literal>default_character_set_catalog</literal></entry>
3881       <entry><type>sql_identifier</type></entry>
3882       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3883      </row>
3884
3885      <row>
3886       <entry><literal>default_character_set_schema</literal></entry>
3887       <entry><type>sql_identifier</type></entry>
3888       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3889      </row>
3890
3891      <row>
3892       <entry><literal>default_character_set_name</literal></entry>
3893       <entry><type>sql_identifier</type></entry>
3894       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3895      </row>
3896
3897      <row>
3898       <entry><literal>sql_path</literal></entry>
3899       <entry><type>character_data</type></entry>
3900       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
3901      </row>
3902     </tbody>
3903    </tgroup>
3904   </table>
3905  </sect1>
3906
3907  <sect1 id="infoschema-sequences">
3908   <title><literal>sequences</literal></title>
3909
3910   <para>
3911    The view <literal>sequences</literal> contains all sequences
3912    defined in the current database.  Only those sequences are shown
3913    that the current user has access to (by way of being the owner or
3914    having some privilege).
3915   </para>
3916
3917   <table>
3918    <title><literal>sequences</literal> Columns</title>
3919
3920    <tgroup cols="3">
3921     <thead>
3922      <row>
3923       <entry>Name</entry>
3924       <entry>Data Type</entry>
3925       <entry>Description</entry>
3926      </row>
3927     </thead>
3928
3929     <tbody>
3930      <row>
3931       <entry><literal>sequence_catalog</literal></entry>
3932       <entry><type>sql_identifier</type></entry>
3933       <entry>Name of the database that contains the sequence (always the current database)</entry>
3934      </row>
3935
3936      <row>
3937       <entry><literal>sequence_schema</literal></entry>
3938       <entry><type>sql_identifier</type></entry>
3939       <entry>Name of the schema that contains the sequence</entry>
3940      </row>
3941
3942      <row>
3943       <entry><literal>sequence_name</literal></entry>
3944       <entry><type>sql_identifier</type></entry>
3945       <entry>Name of the sequence</entry>
3946      </row>
3947
3948      <row>
3949       <entry><literal>data_type</literal></entry>
3950       <entry><type>character_data</type></entry>
3951       <entry>
3952        The data type of the sequence.  In
3953        <productname>PostgreSQL</productname>, this is currently always
3954        <literal>bigint</literal>.
3955       </entry>
3956      </row>
3957
3958      <row>
3959       <entry><literal>numeric_precision</literal></entry>
3960       <entry><type>cardinal_number</type></entry>
3961       <entry>
3962        This column contains the (declared or implicit) precision of
3963        the sequence data type (see above).  The precision indicates
3964        the number of significant digits.  It can be expressed in
3965        decimal (base 10) or binary (base 2) terms, as specified in the
3966        column <literal>numeric_precision_radix</literal>.
3967       </entry>
3968      </row>
3969
3970      <row>
3971       <entry><literal>numeric_precision_radix</literal></entry>
3972       <entry><type>cardinal_number</type></entry>
3973       <entry>
3974        This column indicates in which base the values in the columns
3975        <literal>numeric_precision</literal> and
3976        <literal>numeric_scale</literal> are expressed.  The value is
3977        either 2 or 10.
3978       </entry>
3979      </row>
3980
3981      <row>
3982       <entry><literal>numeric_scale</literal></entry>
3983       <entry><type>cardinal_number</type></entry>
3984       <entry>
3985        This column contains the (declared or implicit) scale of the
3986        sequence data type (see above).  The scale indicates the number
3987        of significant digits to the right of the decimal point.  It
3988        can be expressed in decimal (base 10) or binary (base 2) terms,
3989        as specified in the column
3990        <literal>numeric_precision_radix</literal>.
3991       </entry>
3992      </row>
3993
3994      <row>
3995       <entry><literal>maximum_value</literal></entry>
3996       <entry><type>cardinal_number</type></entry>
3997       <entry>Not yet implemented</entry>
3998      </row>
3999
4000      <row>
4001       <entry><literal>minimum_value</literal></entry>
4002       <entry><type>cardinal_number</type></entry>
4003       <entry>Not yet implemented</entry>
4004      </row>
4005
4006      <row>
4007       <entry><literal>increment</literal></entry>
4008       <entry><type>cardinal_number</type></entry>
4009       <entry>Not yet implemented</entry>
4010      </row>
4011
4012      <row>
4013       <entry><literal>cycle_option</literal></entry>
4014       <entry><type>character_data</type></entry>
4015       <entry>Not yet implemented</entry>
4016      </row>
4017     </tbody>
4018    </tgroup>
4019   </table>
4020  </sect1>
4021
4022  <sect1 id="infoschema-sql-features">
4023   <title><literal>sql_features</literal></title>
4024
4025   <para>
4026    The table <literal>sql_features</literal> contains information
4027    about which formal features defined in the SQL standard are
4028    supported by <productname>PostgreSQL</productname>.  This is the
4029    same information that is presented in <xref linkend="features">.
4030    There you can also find some additional background information.
4031   </para>
4032
4033   <table>
4034    <title><literal>sql_features</literal> Columns</title>
4035
4036    <tgroup cols="3">
4037     <thead>
4038      <row>
4039       <entry>Name</entry>
4040       <entry>Data Type</entry>
4041       <entry>Description</entry>
4042      </row>
4043     </thead>
4044
4045     <tbody>
4046      <row>
4047       <entry><literal>feature_id</literal></entry>
4048       <entry><type>character_data</type></entry>
4049       <entry>Identifier string of the feature</entry>
4050      </row>
4051
4052      <row>
4053       <entry><literal>feature_name</literal></entry>
4054       <entry><type>character_data</type></entry>
4055       <entry>Descriptive name of the feature</entry>
4056      </row>
4057
4058      <row>
4059       <entry><literal>sub_feature_id</literal></entry>
4060       <entry><type>character_data</type></entry>
4061       <entry>Identifier string of the subfeature, or a zero-length string if not a subfeature</entry>
4062      </row>
4063
4064      <row>
4065       <entry><literal>sub_feature_name</literal></entry>
4066       <entry><type>character_data</type></entry>
4067       <entry>Descriptive name of the subfeature, or a zero-length string if not a subfeature</entry>
4068      </row>
4069
4070      <row>
4071       <entry><literal>is_supported</literal></entry>
4072       <entry><type>character_data</type></entry>
4073       <entry>
4074        <literal>YES</literal> if the feature is fully supported by the
4075        current version of <productname>PostgreSQL</>, <literal>NO</literal> if not
4076       </entry>
4077      </row>
4078
4079      <row>
4080       <entry><literal>is_verified_by</literal></entry>
4081       <entry><type>character_data</type></entry>
4082       <entry>
4083        Always null, since the <productname>PostgreSQL</> development group does not
4084        perform formal testing of feature conformance
4085       </entry>
4086      </row>
4087
4088      <row>
4089       <entry><literal>comments</literal></entry>
4090       <entry><type>character_data</type></entry>
4091       <entry>Possibly a comment about the supported status of the feature</entry>
4092      </row>
4093     </tbody>
4094    </tgroup>
4095   </table>
4096  </sect1>
4097
4098  <sect1 id="infoschema-sql-implementation-info">
4099   <title><literal>sql_implementation_info</literal></title>
4100
4101   <para>
4102    The table <literal>sql_implementation_info</literal> contains
4103    information about various aspects that are left
4104    implementation-defined by the SQL standard.  This information is
4105    primarily intended for use in the context of the ODBC interface;
4106    users of other interfaces will probably find this information to be
4107    of little use.  For this reason, the individual implementation
4108    information items are not described here; you will find them in the
4109    description of the ODBC interface.
4110   </para>
4111
4112   <table>
4113    <title><literal>sql_implementation_info</literal> Columns</title>
4114
4115    <tgroup cols="3">
4116     <thead>
4117      <row>
4118       <entry>Name</entry>
4119       <entry>Data Type</entry>
4120       <entry>Description</entry>
4121      </row>
4122     </thead>
4123
4124     <tbody>
4125      <row>
4126       <entry><literal>implementation_info_id</literal></entry>
4127       <entry><type>character_data</type></entry>
4128       <entry>Identifier string of the implementation information item</entry>
4129      </row>
4130
4131      <row>
4132       <entry><literal>implementation_info_name</literal></entry>
4133       <entry><type>character_data</type></entry>
4134       <entry>Descriptive name of the implementation information item</entry>
4135      </row>
4136
4137      <row>
4138       <entry><literal>integer_value</literal></entry>
4139       <entry><type>cardinal_number</type></entry>
4140       <entry>
4141        Value of the implementation information item, or null if the
4142        value is contained in the column
4143        <literal>character_value</literal>
4144       </entry>
4145      </row>
4146
4147      <row>
4148       <entry><literal>character_value</literal></entry>
4149       <entry><type>character_data</type></entry>
4150       <entry>
4151        Value of the implementation information item, or null if the
4152        value is contained in the column
4153        <literal>integer_value</literal>
4154       </entry>
4155      </row>
4156
4157      <row>
4158       <entry><literal>comments</literal></entry>
4159       <entry><type>character_data</type></entry>
4160       <entry>Possibly a comment pertaining to the implementation information item</entry>
4161      </row>
4162     </tbody>
4163    </tgroup>
4164   </table>
4165  </sect1>
4166
4167  <sect1 id="infoschema-sql-languages">
4168   <title><literal>sql_languages</literal></title>
4169
4170   <para>
4171    The table <literal>sql_languages</literal> contains one row for
4172    each SQL language binding that is supported by
4173    <productname>PostgreSQL</productname>.
4174    <productname>PostgreSQL</productname> supports direct SQL and
4175    embedded SQL in C; that is all you will learn from this table.
4176   </para>
4177
4178   <table>
4179    <title><literal>sql_languages</literal> Columns</title>
4180
4181    <tgroup cols="3">
4182     <thead>
4183      <row>
4184       <entry>Name</entry>
4185       <entry>Data Type</entry>
4186       <entry>Description</entry>
4187      </row>
4188     </thead>
4189
4190     <tbody>
4191      <row>
4192       <entry><literal>sql_language_source</literal></entry>
4193       <entry><type>character_data</type></entry>
4194       <entry>
4195        The name of the source of the language definition; always
4196        <literal>ISO 9075</literal>, that is, the SQL standard
4197       </entry>
4198      </row>
4199
4200      <row>
4201       <entry><literal>sql_language_year</literal></entry>
4202       <entry><type>character_data</type></entry>
4203       <entry>
4204        The year the standard referenced in
4205        <literal>sql_language_source</literal> was approved; currently
4206        <literal>2003</>
4207       </entry>
4208      </row>
4209
4210      <row>
4211       <entry><literal>sql_language_conformance</literal></entry>
4212       <entry><type>character_data</type></entry>
4213       <entry>
4214        The standard conformance level for the language binding.  For
4215        ISO 9075:2003 this is always <literal>CORE</literal>.
4216       </entry>
4217      </row>
4218
4219      <row>
4220       <entry><literal>sql_language_integrity</literal></entry>
4221       <entry><type>character_data</type></entry>
4222       <entry>Always null (This value is relevant to an earlier version of the SQL standard.)</entry>
4223      </row>
4224
4225      <row>
4226       <entry><literal>sql_language_implementation</literal></entry>
4227       <entry><type>character_data</type></entry>
4228       <entry>Always null</entry>
4229      </row>
4230
4231      <row>
4232       <entry><literal>sql_language_binding_style</literal></entry>
4233       <entry><type>character_data</type></entry>
4234       <entry>
4235        The language binding style, either <literal>DIRECT</literal> or
4236        <literal>EMBEDDED</literal>
4237       </entry>
4238      </row>
4239
4240      <row>
4241       <entry><literal>sql_language_programming_language</literal></entry>
4242       <entry><type>character_data</type></entry>
4243       <entry>
4244        The programming language, if the binding style is
4245        <literal>EMBEDDED</literal>, else null.  <productname>PostgreSQL</> only
4246        supports the language C.
4247       </entry>
4248      </row>
4249     </tbody>
4250    </tgroup>
4251   </table>
4252  </sect1>
4253
4254  <sect1 id="infoschema-sql-packages">
4255   <title><literal>sql_packages</literal></title>
4256
4257   <para>
4258    The table <literal>sql_packages</literal> contains information
4259    about which feature packages defined in the SQL standard are
4260    supported by <productname>PostgreSQL</productname>.  Refer to <xref
4261    linkend="features"> for background information on feature packages.
4262   </para>
4263
4264   <table>
4265    <title><literal>sql_packages</literal> Columns</title>
4266
4267    <tgroup cols="3">
4268     <thead>
4269      <row>
4270       <entry>Name</entry>
4271       <entry>Data Type</entry>
4272       <entry>Description</entry>
4273      </row>
4274     </thead>
4275
4276     <tbody>
4277      <row>
4278       <entry><literal>feature_id</literal></entry>
4279       <entry><type>character_data</type></entry>
4280       <entry>Identifier string of the package</entry>
4281      </row>
4282
4283      <row>
4284       <entry><literal>feature_name</literal></entry>
4285       <entry><type>character_data</type></entry>
4286       <entry>Descriptive name of the package</entry>
4287      </row>
4288
4289      <row>
4290       <entry><literal>is_supported</literal></entry>
4291       <entry><type>character_data</type></entry>
4292       <entry>
4293        <literal>YES</literal> if the package is fully supported by the
4294        current version of <productname>PostgreSQL</>, <literal>NO</literal> if not
4295       </entry>
4296      </row>
4297
4298      <row>
4299       <entry><literal>is_verified_by</literal></entry>
4300       <entry><type>character_data</type></entry>
4301       <entry>
4302        Always null, since the <productname>PostgreSQL</> development group does not
4303        perform formal testing of feature conformance
4304       </entry>
4305      </row>
4306
4307      <row>
4308       <entry><literal>comments</literal></entry>
4309       <entry><type>character_data</type></entry>
4310       <entry>Possibly a comment about the supported status of the package</entry>
4311      </row>
4312     </tbody>
4313    </tgroup>
4314   </table>
4315  </sect1>
4316
4317  <sect1 id="infoschema-sql-parts">
4318   <title><literal>sql_parts</literal></title>
4319
4320   <para>
4321    The table <literal>sql_parts</literal> contains information about
4322    which of the several parts of the SQL standard are supported by
4323    <productname>PostgreSQL</productname>.
4324   </para>
4325
4326   <table>
4327    <title><literal>sql_parts</literal> Columns</title>
4328
4329    <tgroup cols="3">
4330     <thead>
4331      <row>
4332       <entry>Name</entry>
4333       <entry>Data Type</entry>
4334       <entry>Description</entry>
4335      </row>
4336     </thead>
4337
4338     <tbody>
4339      <row>
4340       <entry><literal>feature_id</literal></entry>
4341       <entry><type>character_data</type></entry>
4342       <entry>An identifier string containing the number of the part</entry>
4343      </row>
4344
4345      <row>
4346       <entry><literal>feature_name</literal></entry>
4347       <entry><type>character_data</type></entry>
4348       <entry>Descriptive name of the part</entry>
4349      </row>
4350
4351      <row>
4352       <entry><literal>is_supported</literal></entry>
4353       <entry><type>character_data</type></entry>
4354       <entry>
4355        <literal>YES</literal> if the part is fully supported by the
4356        current version of <productname>PostgreSQL</>,
4357        <literal>NO</literal> if not
4358       </entry>
4359      </row>
4360
4361      <row>
4362       <entry><literal>is_verified_by</literal></entry>
4363       <entry><type>character_data</type></entry>
4364       <entry>
4365        Always null, since the <productname>PostgreSQL</> development group does not
4366        perform formal testing of feature conformance
4367       </entry>
4368      </row>
4369
4370      <row>
4371       <entry><literal>comments</literal></entry>
4372       <entry><type>character_data</type></entry>
4373       <entry>Possibly a comment about the supported status of the part</entry>
4374      </row>
4375     </tbody>
4376    </tgroup>
4377   </table>
4378  </sect1>
4379
4380  <sect1 id="infoschema-sql-sizing">
4381   <title><literal>sql_sizing</literal></title>
4382
4383   <para>
4384    The table <literal>sql_sizing</literal> contains information about
4385    various size limits and maximum values in
4386    <productname>PostgreSQL</productname>.  This information is
4387    primarily intended for use in the context of the ODBC interface;
4388    users of other interfaces will probably find this information to be
4389    of little use.  For this reason, the individual sizing items are
4390    not described here; you will find them in the description of the
4391    ODBC interface.
4392   </para>
4393
4394   <table>
4395    <title><literal>sql_sizing</literal> Columns</title>
4396
4397    <tgroup cols="3">
4398     <thead>
4399      <row>
4400       <entry>Name</entry>
4401       <entry>Data Type</entry>
4402       <entry>Description</entry>
4403      </row>
4404     </thead>
4405
4406     <tbody>
4407      <row>
4408       <entry><literal>sizing_id</literal></entry>
4409       <entry><type>cardinal_number</type></entry>
4410       <entry>Identifier of the sizing item</entry>
4411      </row>
4412
4413      <row>
4414       <entry><literal>sizing_name</literal></entry>
4415       <entry><type>character_data</type></entry>
4416       <entry>Descriptive name of the sizing item</entry>
4417      </row>
4418
4419      <row>
4420       <entry><literal>supported_value</literal></entry>
4421       <entry><type>cardinal_number</type></entry>
4422       <entry>
4423        Value of the sizing item, or 0 if the size is unlimited or
4424        cannot be determined, or null if the features for which the
4425        sizing item is applicable are not supported
4426       </entry>
4427      </row>
4428
4429      <row>
4430       <entry><literal>comments</literal></entry>
4431       <entry><type>character_data</type></entry>
4432       <entry>Possibly a comment pertaining to the sizing item</entry>
4433      </row>
4434     </tbody>
4435    </tgroup>
4436   </table>
4437  </sect1>
4438
4439  <sect1 id="infoschema-sql-sizing-profiles">
4440   <title><literal>sql_sizing_profiles</literal></title>
4441
4442   <para>
4443    The table <literal>sql_sizing_profiles</literal> contains
4444    information about the <literal>sql_sizing</literal> values that are
4445    required by various profiles of the SQL standard.  <productname>PostgreSQL</> does
4446    not track any SQL profiles, so this table is empty.
4447   </para>
4448
4449   <table>
4450    <title><literal>sql_sizing_profiles</literal> Columns</title>
4451
4452    <tgroup cols="3">
4453     <thead>
4454      <row>
4455       <entry>Name</entry>
4456       <entry>Data Type</entry>
4457       <entry>Description</entry>
4458      </row>
4459     </thead>
4460
4461     <tbody>
4462      <row>
4463       <entry><literal>sizing_id</literal></entry>
4464       <entry><type>cardinal_number</type></entry>
4465       <entry>Identifier of the sizing item</entry>
4466      </row>
4467
4468      <row>
4469       <entry><literal>sizing_name</literal></entry>
4470       <entry><type>character_data</type></entry>
4471       <entry>Descriptive name of the sizing item</entry>
4472      </row>
4473
4474      <row>
4475       <entry><literal>profile_id</literal></entry>
4476       <entry><type>character_data</type></entry>
4477       <entry>Identifier string of a profile</entry>
4478      </row>
4479
4480      <row>
4481       <entry><literal>required_value</literal></entry>
4482       <entry><type>cardinal_number</type></entry>
4483       <entry>
4484        The value required by the SQL profile for the sizing item, or 0
4485        if the profile places no limit on the sizing item, or null if
4486        the profile does not require any of the features for which the
4487        sizing item is applicable
4488       </entry>
4489      </row>
4490
4491      <row>
4492       <entry><literal>comments</literal></entry>
4493       <entry><type>character_data</type></entry>
4494       <entry>Possibly a comment pertaining to the sizing item within the profile</entry>
4495      </row>
4496     </tbody>
4497    </tgroup>
4498   </table>
4499  </sect1>
4500
4501  <sect1 id="infoschema-table-constraints">
4502   <title><literal>table_constraints</literal></title>
4503
4504   <para>
4505    The view <literal>table_constraints</literal> contains all
4506    constraints belonging to tables that the current user owns or has
4507    some non-SELECT privilege on.
4508   </para>
4509
4510   <table>
4511    <title><literal>table_constraints</literal> Columns</title>
4512
4513    <tgroup cols="3">
4514     <thead>
4515      <row>
4516       <entry>Name</entry>
4517       <entry>Data Type</entry>
4518       <entry>Description</entry>
4519      </row>
4520     </thead>
4521
4522     <tbody>
4523      <row>
4524       <entry><literal>constraint_catalog</literal></entry>
4525       <entry><type>sql_identifier</type></entry>
4526       <entry>Name of the database that contains the constraint (always the current database)</entry>
4527      </row>
4528
4529      <row>
4530       <entry><literal>constraint_schema</literal></entry>
4531       <entry><type>sql_identifier</type></entry>
4532       <entry>Name of the schema that contains the constraint</entry>
4533      </row>
4534
4535      <row>
4536       <entry><literal>constraint_name</literal></entry>
4537       <entry><type>sql_identifier</type></entry>
4538       <entry>Name of the constraint</entry>
4539      </row>
4540
4541      <row>
4542       <entry><literal>table_catalog</literal></entry>
4543       <entry><type>sql_identifier</type></entry>
4544       <entry>Name of the database that contains the table (always the current database)</entry>
4545      </row>
4546
4547      <row>
4548       <entry><literal>table_schema</literal></entry>
4549       <entry><type>sql_identifier</type></entry>
4550       <entry>Name of the schema that contains the table</entry>
4551      </row>
4552
4553      <row>
4554       <entry><literal>table_name</literal></entry>
4555       <entry><type>sql_identifier</type></entry>
4556       <entry>Name of the table</entry>
4557      </row>
4558
4559      <row>
4560       <entry><literal>constraint_type</literal></entry>
4561       <entry><type>character_data</type></entry>
4562       <entry>
4563        Type of the constraint: <literal>CHECK</literal>,
4564        <literal>FOREIGN KEY</literal>, <literal>PRIMARY KEY</literal>,
4565        or <literal>UNIQUE</literal>
4566       </entry>
4567      </row>
4568
4569      <row>
4570       <entry><literal>is_deferrable</literal></entry>
4571       <entry><type>character_data</type></entry>
4572       <entry><literal>YES</literal> if the constraint is deferrable, <literal>NO</literal> if not</entry>
4573      </row>
4574
4575      <row>
4576       <entry><literal>initially_deferred</literal></entry>
4577       <entry><type>character_data</type></entry>
4578       <entry><literal>YES</literal> if the constraint is deferrable and initially deferred, <literal>NO</literal> if not</entry>
4579      </row>
4580     </tbody>
4581    </tgroup>
4582   </table>
4583  </sect1>
4584
4585  <sect1 id="infoschema-table-privileges">
4586   <title><literal>table_privileges</literal></title>
4587
4588   <para>
4589    The view <literal>table_privileges</literal> identifies all
4590    privileges granted on tables or views to a currently enabled role
4591    or by a currently enabled role.  There is one row for each
4592    combination of table, grantor, and grantee.
4593   </para>
4594
4595   <table>
4596    <title><literal>table_privileges</literal> Columns</title>
4597
4598    <tgroup cols="3">
4599     <thead>
4600      <row>
4601       <entry>Name</entry>
4602       <entry>Data Type</entry>
4603       <entry>Description</entry>
4604      </row>
4605     </thead>
4606
4607     <tbody>
4608      <row>
4609       <entry><literal>grantor</literal></entry>
4610       <entry><type>sql_identifier</type></entry>
4611       <entry>Name of the role that granted the privilege</entry>
4612      </row>
4613
4614      <row>
4615       <entry><literal>grantee</literal></entry>
4616       <entry><type>sql_identifier</type></entry>
4617       <entry>Name of the role that the privilege was granted to</entry>
4618      </row>
4619
4620      <row>
4621       <entry><literal>table_catalog</literal></entry>
4622       <entry><type>sql_identifier</type></entry>
4623       <entry>Name of the database that contains the table (always the current database)</entry>
4624      </row>
4625
4626      <row>
4627       <entry><literal>table_schema</literal></entry>
4628       <entry><type>sql_identifier</type></entry>
4629       <entry>Name of the schema that contains the table</entry>
4630      </row>
4631
4632      <row>
4633       <entry><literal>table_name</literal></entry>
4634       <entry><type>sql_identifier</type></entry>
4635       <entry>Name of the table</entry>
4636      </row>
4637
4638      <row>
4639       <entry><literal>privilege_type</literal></entry>
4640       <entry><type>character_data</type></entry>
4641       <entry>
4642        Type of the privilege: <literal>SELECT</literal>,
4643        <literal>INSERT</literal>, <literal>UPDATE</literal>,
4644        <literal>DELETE</literal>, <literal>TRUNCATE</literal>,
4645        <literal>REFERENCES</literal>, or <literal>TRIGGER</literal>
4646       </entry>
4647      </row>
4648
4649      <row>
4650       <entry><literal>is_grantable</literal></entry>
4651       <entry><type>character_data</type></entry>
4652       <entry><literal>YES</literal> if the privilege is grantable, <literal>NO</literal> if not</entry>
4653      </row>
4654
4655      <row>
4656       <entry><literal>with_hierarchy</literal></entry>
4657       <entry><type>character_data</type></entry>
4658       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4659      </row>
4660     </tbody>
4661    </tgroup>
4662   </table>
4663  </sect1>
4664
4665  <sect1 id="infoschema-tables">
4666   <title><literal>tables</literal></title>
4667
4668   <para>
4669    The view <literal>tables</literal> contains all tables and views
4670    defined in the current database.  Only those tables and views are
4671    shown that the current user has access to (by way of being the
4672    owner or having some privilege).
4673   </para>
4674
4675   <table>
4676    <title><literal>tables</literal> Columns</title>
4677
4678    <tgroup cols="3">
4679     <thead>
4680      <row>
4681       <entry>Name</entry>
4682       <entry>Data Type</entry>
4683       <entry>Description</entry>
4684      </row>
4685     </thead>
4686
4687     <tbody>
4688      <row>
4689       <entry><literal>table_catalog</literal></entry>
4690       <entry><type>sql_identifier</type></entry>
4691       <entry>Name of the database that contains the table (always the current database)</entry>
4692      </row>
4693
4694      <row>
4695       <entry><literal>table_schema</literal></entry>
4696       <entry><type>sql_identifier</type></entry>
4697       <entry>Name of the schema that contains the table</entry>
4698      </row>
4699
4700      <row>
4701       <entry><literal>table_name</literal></entry>
4702       <entry><type>sql_identifier</type></entry>
4703       <entry>Name of the table</entry>
4704      </row>
4705
4706      <row>
4707       <entry><literal>table_type</literal></entry>
4708       <entry><type>character_data</type></entry>
4709       <entry>
4710        Type of the table: <literal>BASE TABLE</literal> for a
4711        persistent base table (the normal table type),
4712        <literal>VIEW</literal> for a view, or <literal>LOCAL
4713        TEMPORARY</literal> for a temporary table
4714       </entry>
4715      </row>
4716
4717      <row>
4718       <entry><literal>self_referencing_column_name</literal></entry>
4719       <entry><type>sql_identifier</type></entry>
4720       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4721      </row>
4722
4723      <row>
4724       <entry><literal>reference_generation</literal></entry>
4725       <entry><type>character_data</type></entry>
4726       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4727      </row>
4728
4729      <row>
4730       <entry><literal>user_defined_type_catalog</literal></entry>
4731       <entry><type>sql_identifier</type></entry>
4732       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4733      </row>
4734
4735      <row>
4736       <entry><literal>user_defined_type_schema</literal></entry>
4737       <entry><type>sql_identifier</type></entry>
4738       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4739      </row>
4740
4741      <row>
4742       <entry><literal>user_defined_type_name</literal></entry>
4743       <entry><type>sql_identifier</type></entry>
4744       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4745      </row>
4746
4747      <row>
4748       <entry><literal>is_insertable_into</literal></entry>
4749       <entry><type>character_data</type></entry>
4750       <entry>
4751        <literal>YES</literal> if the table is insertable into,
4752        <literal>NO</literal> if not (Base tables are always insertable
4753        into, views not necessarily.)
4754       </entry>
4755      </row>
4756
4757      <row>
4758       <entry><literal>is_typed</literal></entry>
4759       <entry><type>character_data</type></entry>
4760       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4761      </row>
4762
4763      <row>
4764       <entry><literal>commit_action</literal></entry>
4765       <entry><type>character_data</type></entry>
4766       <entry>
4767        If the table is a temporary table, then
4768        <literal>PRESERVE</literal>, else null.  (The SQL standard
4769        defines other commit actions for temporary tables, which are
4770        not supported by <productname>PostgreSQL</>.)
4771       </entry>
4772      </row>
4773     </tbody>
4774    </tgroup>
4775   </table>
4776  </sect1>
4777
4778  <sect1 id="infoschema-triggers">
4779   <title><literal>triggers</literal></title>
4780
4781   <para>
4782    The view <literal>triggers</literal> contains all triggers defined
4783    in the current database on tables that the current user owns or has
4784    some non-SELECT privilege on.
4785   </para>
4786
4787   <table>
4788    <title><literal>triggers</literal> Columns</title>
4789
4790    <tgroup cols="3">
4791     <thead>
4792      <row>
4793       <entry>Name</entry>
4794       <entry>Data Type</entry>
4795       <entry>Description</entry>
4796      </row>
4797     </thead>
4798
4799     <tbody>
4800      <row>
4801       <entry><literal>trigger_catalog</literal></entry>
4802       <entry><type>sql_identifier</type></entry>
4803       <entry>Name of the database that contains the trigger (always the current database)</entry>
4804      </row>
4805
4806      <row>
4807       <entry><literal>trigger_schema</literal></entry>
4808       <entry><type>sql_identifier</type></entry>
4809       <entry>Name of the schema that contains the trigger</entry>
4810      </row>
4811
4812      <row>
4813       <entry><literal>trigger_name</literal></entry>
4814       <entry><type>sql_identifier</type></entry>
4815       <entry>Name of the trigger</entry>
4816      </row>
4817
4818      <row>
4819       <entry><literal>event_manipulation</literal></entry>
4820       <entry><type>character_data</type></entry>
4821       <entry>
4822        Event that fires the trigger (<literal>INSERT</literal>,
4823        <literal>UPDATE</literal>, or <literal>DELETE</literal>)
4824       </entry>
4825      </row>
4826
4827      <row>
4828       <entry><literal>event_object_catalog</literal></entry>
4829       <entry><type>sql_identifier</type></entry>
4830       <entry>
4831        Name of the database that contains the table that the trigger
4832        is defined on (always the current database)
4833       </entry>
4834      </row>
4835
4836      <row>
4837       <entry><literal>event_object_schema</literal></entry>
4838       <entry><type>sql_identifier</type></entry>
4839       <entry>Name of the schema that contains the table that the trigger is defined on</entry>
4840      </row>
4841
4842      <row>
4843       <entry><literal>event_object_table</literal></entry>
4844       <entry><type>sql_identifier</type></entry>
4845       <entry>Name of the table that the trigger is defined on</entry>
4846      </row>
4847
4848      <row>
4849       <entry><literal>action_order</literal></entry>
4850       <entry><type>cardinal_number</type></entry>
4851       <entry>Not yet implemented</entry>
4852      </row>
4853
4854      <row>
4855       <entry><literal>action_condition</literal></entry>
4856       <entry><type>character_data</type></entry>
4857       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4858      </row>
4859
4860      <row>
4861       <entry><literal>action_statement</literal></entry>
4862       <entry><type>character_data</type></entry>
4863       <entry>
4864        Statement that is executed by the trigger (currently always
4865        <literal>EXECUTE PROCEDURE
4866        <replaceable>function</replaceable>(...)</literal>)
4867       </entry>
4868      </row>
4869
4870      <row>
4871       <entry><literal>action_orientation</literal></entry>
4872       <entry><type>character_data</type></entry>
4873       <entry>
4874        Identifies whether the trigger fires once for each processed
4875        row or once for each statement (<literal>ROW</literal> or
4876        <literal>STATEMENT</literal>)
4877       </entry>
4878      </row>
4879
4880      <row>
4881       <entry><literal>condition_timing</literal></entry>
4882       <entry><type>character_data</type></entry>
4883       <entry>
4884        Time at which the trigger fires (<literal>BEFORE</literal> or
4885        <literal>AFTER</literal>)
4886       </entry>
4887      </row>
4888
4889      <row>
4890       <entry><literal>condition_reference_old_table</literal></entry>
4891       <entry><type>sql_identifier</type></entry>
4892       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4893      </row>
4894
4895      <row>
4896       <entry><literal>condition_reference_new_table</literal></entry>
4897       <entry><type>sql_identifier</type></entry>
4898       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4899      </row>
4900
4901      <row>
4902       <entry><literal>condition_reference_old_row</literal></entry>
4903       <entry><type>sql_identifier</type></entry>
4904       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4905      </row>
4906
4907      <row>
4908       <entry><literal>condition_reference_new_row</literal></entry>
4909       <entry><type>sql_identifier</type></entry>
4910       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4911      </row>
4912
4913      <row>
4914       <entry><literal>created</literal></entry>
4915       <entry><type>time_stamp</type></entry>
4916       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
4917      </row>
4918     </tbody>
4919    </tgroup>
4920   </table>
4921
4922   <para>
4923    Triggers in <productname>PostgreSQL</productname> have two
4924    incompatibilities with the SQL standard that affect the
4925    representation in the information schema.  First, trigger names are
4926    local to the table in <productname>PostgreSQL</productname>, rather
4927    than being independent schema objects.  Therefore there can be duplicate
4928    trigger names defined in one schema, as long as they belong to
4929    different tables.  (<literal>trigger_catalog</literal> and
4930    <literal>trigger_schema</literal> are really the values pertaining
4931    to the table that the trigger is defined on.)  Second, triggers can
4932    be defined to fire on multiple events in
4933    <productname>PostgreSQL</productname> (e.g., <literal>ON INSERT OR
4934    UPDATE</literal>), whereas the SQL standard only allows one.  If a
4935    trigger is defined to fire on multiple events, it is represented as
4936    multiple rows in the information schema, one for each type of
4937    event.  As a consequence of these two issues, the primary key of
4938    the view <literal>triggers</literal> is really
4939    <literal>(trigger_catalog, trigger_schema, trigger_name,
4940    event_object_table, event_manipulation)</literal> instead of
4941    <literal>(trigger_catalog, trigger_schema, trigger_name)</literal>,
4942    which is what the SQL standard specifies.  Nonetheless, if you
4943    define your triggers in a manner that conforms with the SQL
4944    standard (trigger names unique in the schema and only one event
4945    type per trigger), this will not affect you.
4946   </para>
4947  </sect1>
4948
4949  <sect1 id="infoschema-usage-privileges">
4950   <title><literal>usage_privileges</literal></title>
4951
4952   <para>
4953    The view <literal>usage_privileges</literal> identifies
4954    <literal>USAGE</literal> privileges granted on various kinds of
4955    objects to a currently enabled role or by a currently enabled role.
4956    In <productname>PostgreSQL</productname>, this currently applies to
4957    domains, foreign-data wrappers, and foreign servers.  There is one
4958    row for each combination of object, grantor, and grantee.
4959   </para>
4960
4961   <para>
4962    Since domains do not have real privileges
4963    in <productname>PostgreSQL</productname>, this view shows implicit
4964    non-grantable <literal>USAGE</literal> privileges granted by the
4965    owner to <literal>PUBLIC</literal> for all domains.  The other
4966    object types, however, show real privileges.
4967   </para>
4968
4969   <table>
4970    <title><literal>usage_privileges</literal> Columns</title>
4971
4972    <tgroup cols="3">
4973     <thead>
4974      <row>
4975       <entry>Name</entry>
4976       <entry>Data Type</entry>
4977       <entry>Description</entry>
4978      </row>
4979     </thead>
4980
4981     <tbody>
4982      <row>
4983       <entry><literal>grantor</literal></entry>
4984       <entry><type>sql_identifier</type></entry>
4985       <entry>Name of the role that granted the privilege</entry>
4986      </row>
4987
4988      <row>
4989       <entry><literal>grantee</literal></entry>
4990       <entry><type>sql_identifier</type></entry>
4991       <entry>Name of the role that the privilege was granted to</entry>
4992      </row>
4993
4994      <row>
4995       <entry><literal>object_catalog</literal></entry>
4996       <entry><type>sql_identifier</type></entry>
4997       <entry>Name of the database containing the object (always the current database)</entry>
4998      </row>
4999
5000      <row>
5001       <entry><literal>object_schema</literal></entry>
5002       <entry><type>sql_identifier</type></entry>
5003       <entry>Name of the schema containing the object, if applicable,
5004       else an empty string</entry>
5005      </row>
5006
5007      <row>
5008       <entry><literal>object_name</literal></entry>
5009       <entry><type>sql_identifier</type></entry>
5010       <entry>Name of the object</entry>
5011      </row>
5012
5013      <row>
5014       <entry><literal>object_type</literal></entry>
5015       <entry><type>character_data</type></entry>
5016       <entry><literal>DOMAIN</literal> or <literal>FOREIGN DATA WRAPPER</literal> or <literal>FOREIGN SERVER</literal></entry>
5017      </row>
5018
5019      <row>
5020       <entry><literal>privilege_type</literal></entry>
5021       <entry><type>character_data</type></entry>
5022       <entry>Always <literal>USAGE</literal></entry>
5023      </row>
5024
5025      <row>
5026       <entry><literal>is_grantable</literal></entry>
5027       <entry><type>character_data</type></entry>
5028       <entry><literal>YES</literal> if the privilege is grantable, <literal>NO</literal> if not</entry>
5029      </row>
5030     </tbody>
5031    </tgroup>
5032   </table>
5033  </sect1>
5034
5035  <sect1 id="infoschema-user-mapping-options">
5036   <title><literal>user_mapping_options</literal></title>
5037
5038   <para>
5039    The view <literal>user_mapping_options</literal> contains all the
5040    options defined for user mappings in the current database.  Only
5041    those user mappings are shown where the current user has access to
5042    the corresponding foreign server (by way of being the owner or
5043    having some privilege).
5044   </para>
5045
5046   <table>
5047    <title><literal>user_mapping_options</literal> Columns</title>
5048
5049    <tgroup cols="3">
5050     <thead>
5051      <row>
5052       <entry>Name</entry>
5053       <entry>Data Type</entry>
5054       <entry>Description</entry>
5055      </row>
5056     </thead>
5057
5058     <tbody>
5059      <row>
5060       <entry><literal>authorization_identifier</literal></entry>
5061       <entry><type>sql_identifier</type></entry>
5062       <entry>Name of the user being mapped,
5063       or <literal>PUBLIC</literal> if the mapping is public</entry>
5064      </row>
5065
5066      <row>
5067       <entry><literal>foreign_server_catalog</literal></entry>
5068       <entry><type>sql_identifier</type></entry>
5069       <entry>Name of the database that the foreign server used by this
5070       mapping is defined in (always the current database)</entry>
5071      </row>
5072
5073      <row>
5074       <entry><literal>foreign_server_name</literal></entry>
5075       <entry><type>sql_identifier</type></entry>
5076       <entry>Name of the foreign server used by this mapping</entry>
5077      </row>
5078
5079      <row>
5080       <entry><literal>option_name</literal></entry>
5081       <entry><type>sql_identifier</type></entry>
5082       <entry>Name of an option</entry>
5083      </row>
5084
5085      <row>
5086       <entry><literal>option_value</literal></entry>
5087       <entry><type>character_data</type></entry>
5088       <entry>Value of the option.  This column will show as null
5089       unless the current user is the user being mapped, or the mapping
5090       is for <literal>PUBLIC</literal> and the current user is the
5091       server owner, or the current user is a superuser.  The intent is
5092       to protect password information stored as user mapping
5093       option.</entry>
5094      </row>
5095     </tbody>
5096    </tgroup>
5097   </table>
5098  </sect1>
5099
5100  <sect1 id="infoschema-user-mappings">
5101   <title><literal>user_mappings</literal></title>
5102
5103   <para>
5104    The view <literal>user_mappings</literal> contains all user
5105    mappings defined in the current database.  Only those user mappings
5106    are shown where the current user has access to the corresponding
5107    foreign server (by way of being the owner or having some
5108    privilege).
5109   </para>
5110
5111   <table>
5112    <title><literal>user_mappings</literal> Columns</title>
5113
5114    <tgroup cols="3">
5115     <thead>
5116      <row>
5117       <entry>Name</entry>
5118       <entry>Data Type</entry>
5119       <entry>Description</entry>
5120      </row>
5121     </thead>
5122
5123     <tbody>
5124      <row>
5125       <entry><literal>authorization_identifier</literal></entry>
5126       <entry><type>sql_identifier</type></entry>
5127       <entry>Name of the user being mapped,
5128       or <literal>PUBLIC</literal> if the mapping is public</entry>
5129      </row>
5130
5131      <row>
5132       <entry><literal>foreign_server_catalog</literal></entry>
5133       <entry><type>sql_identifier</type></entry>
5134       <entry>Name of the database that the foreign server used by this
5135       mapping is defined in (always the current database)</entry>
5136      </row>
5137
5138      <row>
5139       <entry><literal>foreign_server_name</literal></entry>
5140       <entry><type>sql_identifier</type></entry>
5141       <entry>Name of the foreign server used by this mapping</entry>
5142      </row>
5143     </tbody>
5144    </tgroup>
5145   </table>
5146  </sect1>
5147
5148  <sect1 id="infoschema-view-column-usage">
5149   <title><literal>view_column_usage</literal></title>
5150
5151   <para>
5152    The view <literal>view_column_usage</literal> identifies all
5153    columns that are used in the query expression of a view (the
5154    <command>SELECT</command> statement that defines the view).  A
5155    column is only included if the table that contains the column is
5156    owned by a currently enabled role.
5157   </para>
5158
5159   <note>
5160    <para>
5161     Columns of system tables are not included.  This should be fixed
5162     sometime.
5163    </para>
5164   </note>
5165
5166   <table>
5167    <title><literal>view_column_usage</literal> Columns</title>
5168
5169    <tgroup cols="3">
5170     <thead>
5171      <row>
5172       <entry>Name</entry>
5173       <entry>Data Type</entry>
5174       <entry>Description</entry>
5175      </row>
5176     </thead>
5177
5178     <tbody>
5179      <row>
5180       <entry><literal>view_catalog</literal></entry>
5181       <entry><type>sql_identifier</type></entry>
5182       <entry>Name of the database that contains the view (always the current database)</entry>
5183      </row>
5184
5185      <row>
5186       <entry><literal>view_schema</literal></entry>
5187       <entry><type>sql_identifier</type></entry>
5188       <entry>Name of the schema that contains the view</entry>
5189      </row>
5190
5191      <row>
5192       <entry><literal>view_name</literal></entry>
5193       <entry><type>sql_identifier</type></entry>
5194       <entry>Name of the view</entry>
5195      </row>
5196
5197      <row>
5198       <entry><literal>table_catalog</literal></entry>
5199       <entry><type>sql_identifier</type></entry>
5200       <entry>
5201        Name of the database that contains the table that contains the
5202        column that is used by the view (always the current database)
5203       </entry>
5204      </row>
5205
5206      <row>
5207       <entry><literal>table_schema</literal></entry>
5208       <entry><type>sql_identifier</type></entry>
5209       <entry>
5210        Name of the schema that contains the table that contains the
5211        column that is used by the view
5212       </entry>
5213      </row>
5214
5215      <row>
5216       <entry><literal>table_name</literal></entry>
5217       <entry><type>sql_identifier</type></entry>
5218       <entry>
5219        Name of the table that contains the column that is used by the
5220        view
5221       </entry>
5222      </row>
5223
5224      <row>
5225       <entry><literal>column_name</literal></entry>
5226       <entry><type>sql_identifier</type></entry>
5227       <entry>Name of the column that is used by the view</entry>
5228      </row>
5229     </tbody>
5230    </tgroup>
5231   </table>
5232  </sect1>
5233
5234  <sect1 id="infoschema-view-routine-usage">
5235   <title><literal>view_routine_usage</literal></title>
5236
5237   <para>
5238    The view <literal>view_routine_usage</literal> identifies all
5239    routines (functions and procedures) that are used in the query
5240    expression of a view (the <command>SELECT</command> statement that
5241    defines the view).  A routine is only included if that routine is
5242    owned by a currently enabled role.
5243   </para>
5244
5245   <table>
5246    <title><literal>view_routine_usage</literal> Columns</title>
5247
5248    <tgroup cols="3">
5249     <thead>
5250      <row>
5251       <entry>Name</entry>
5252       <entry>Data Type</entry>
5253       <entry>Description</entry>
5254      </row>
5255     </thead>
5256
5257     <tbody>
5258      <row>
5259       <entry><literal>table_catalog</literal></entry>
5260       <entry><literal>sql_identifier</literal></entry>
5261       <entry>Name of the database containing the view (always the current database)</entry>
5262      </row>
5263
5264      <row>
5265       <entry><literal>table_schema</literal></entry>
5266       <entry><literal>sql_identifier</literal></entry>
5267       <entry>Name of the schema containing the view</entry>
5268      </row>
5269
5270      <row>
5271       <entry><literal>table_name</literal></entry>
5272       <entry><literal>sql_identifier</literal></entry>
5273       <entry>Name of the view</entry>
5274      </row>
5275
5276      <row>
5277       <entry><literal>specific_catalog</literal></entry>
5278       <entry><literal>sql_identifier</literal></entry>
5279       <entry>Name of the database containing the function (always the current database)</entry>
5280      </row>
5281
5282      <row>
5283       <entry><literal>specific_schema</literal></entry>
5284       <entry><literal>sql_identifier</literal></entry>
5285       <entry>Name of the schema containing the function</entry>
5286      </row>
5287
5288      <row>
5289       <entry><literal>specific_name</literal></entry>
5290       <entry><literal>sql_identifier</literal></entry>
5291       <entry>
5292        The <quote>specific name</quote> of the function.  See <xref
5293        linkend="infoschema-routines"> for more information.
5294       </entry>
5295      </row>
5296     </tbody>
5297    </tgroup>
5298   </table>
5299  </sect1>
5300
5301  <sect1 id="infoschema-view-table-usage">
5302   <title><literal>view_table_usage</literal></title>
5303
5304   <para>
5305    The view <literal>view_table_usage</literal> identifies all tables
5306    that are used in the query expression of a view (the
5307    <command>SELECT</command> statement that defines the view).  A
5308    table is only included if that table is owned by a currently
5309    enabled role.
5310   </para>
5311
5312   <note>
5313    <para>
5314     System tables are not included.  This should be fixed sometime.
5315    </para>
5316   </note>
5317
5318   <table>
5319    <title><literal>view_table_usage</literal> Columns</title>
5320
5321    <tgroup cols="3">
5322     <thead>
5323      <row>
5324       <entry>Name</entry>
5325       <entry>Data Type</entry>
5326       <entry>Description</entry>
5327      </row>
5328     </thead>
5329
5330     <tbody>
5331      <row>
5332       <entry><literal>view_catalog</literal></entry>
5333       <entry><type>sql_identifier</type></entry>
5334       <entry>Name of the database that contains the view (always the current database)</entry>
5335      </row>
5336
5337      <row>
5338       <entry><literal>view_schema</literal></entry>
5339       <entry><type>sql_identifier</type></entry>
5340       <entry>Name of the schema that contains the view</entry>
5341      </row>
5342
5343      <row>
5344       <entry><literal>view_name</literal></entry>
5345       <entry><type>sql_identifier</type></entry>
5346       <entry>Name of the view</entry>
5347      </row>
5348
5349      <row>
5350       <entry><literal>table_catalog</literal></entry>
5351       <entry><type>sql_identifier</type></entry>
5352       <entry>
5353        Name of the database that contains the table that is
5354        used by the view (always the current database)
5355       </entry>
5356      </row>
5357
5358      <row>
5359       <entry><literal>table_schema</literal></entry>
5360       <entry><type>sql_identifier</type></entry>
5361       <entry>
5362        Name of the schema that contains the table that is used by the
5363        view
5364       </entry>
5365      </row>
5366
5367      <row>
5368       <entry><literal>table_name</literal></entry>
5369       <entry><type>sql_identifier</type></entry>
5370       <entry>
5371        Name of the table that is used by the view
5372       </entry>
5373      </row>
5374     </tbody>
5375    </tgroup>
5376   </table>
5377  </sect1>
5378
5379  <sect1 id="infoschema-views">
5380   <title><literal>views</literal></title>
5381
5382   <para>
5383    The view <literal>views</literal> contains all views defined in the
5384    current database.  Only those views are shown that the current user
5385    has access to (by way of being the owner or having some privilege).
5386   </para>
5387
5388   <table>
5389    <title><literal>views</literal> Columns</title>
5390
5391    <tgroup cols="3">
5392     <thead>
5393      <row>
5394       <entry>Name</entry>
5395       <entry>Data Type</entry>
5396       <entry>Description</entry>
5397      </row>
5398     </thead>
5399
5400     <tbody>
5401      <row>
5402       <entry><literal>table_catalog</literal></entry>
5403       <entry><type>sql_identifier</type></entry>
5404       <entry>Name of the database that contains the view (always the current database)</entry>
5405      </row>
5406
5407      <row>
5408       <entry><literal>table_schema</literal></entry>
5409       <entry><type>sql_identifier</type></entry>
5410       <entry>Name of the schema that contains the view</entry>
5411      </row>
5412
5413      <row>
5414       <entry><literal>table_name</literal></entry>
5415       <entry><type>sql_identifier</type></entry>
5416       <entry>Name of the view</entry>
5417      </row>
5418
5419      <row>
5420       <entry><literal>view_definition</literal></entry>
5421       <entry><type>character_data</type></entry>
5422       <entry>
5423        Query expression defining the view (null if the view is not
5424        owned by a currently enabled role)
5425       </entry>
5426      </row>
5427
5428      <row>
5429       <entry><literal>check_option</literal></entry>
5430       <entry><type>character_data</type></entry>
5431       <entry>Applies to a feature not available in <productname>PostgreSQL</></entry>
5432      </row>
5433
5434      <row>
5435       <entry><literal>is_updatable</literal></entry>
5436       <entry><type>character_data</type></entry>
5437       <entry>
5438        <literal>YES</literal> if the view is updatable (allows
5439        <command>UPDATE</command> and <command>DELETE</command>),
5440        <literal>NO</literal> if not
5441       </entry>
5442      </row>
5443
5444      <row>
5445       <entry><literal>is_insertable_into</literal></entry>
5446       <entry><type>character_data</type></entry>
5447       <entry>
5448        <literal>YES</literal> if the view is insertable into (allows
5449        <command>INSERT</command>), <literal>NO</literal> if not
5450       </entry>
5451      </row>
5452     </tbody>
5453    </tgroup>
5454   </table>
5455  </sect1>
5456
5457 </chapter>