src/include/utils/rel.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * rel.h
   4  *        POSTGRES relation descriptor (a/k/a relcache entry) definitions.
   5  *
   6  *
   7  * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  * src/include/utils/rel.h
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #ifndef REL_H
  15 #define REL_H
  16
  17 #include "access/tupdesc.h"
  18 #include "access/xlog.h"
  19 #include "catalog/catalog.h"
  20 #include "catalog/pg_class.h"
  21 #include "catalog/pg_index.h"
  22 #include "catalog/pg_publication.h"
  23 #include "nodes/bitmapset.h"
  24 #include "partitioning/partdefs.h"
  25 #include "rewrite/prs2lock.h"
  26 #include "storage/block.h"
  27 #include "storage/relfilelocator.h"
  28 #include "storage/smgr.h"
  29 #include "utils/relcache.h"
  30 #include "utils/reltrigger.h"
  31
  32
  33 /*
  34  * LockRelId and LockInfo really belong to lmgr.h, but it's more convenient
  35  * to declare them here so we can have a LockInfoData field in a Relation.
  36  */
  37
  38 typedef struct LockRelId
  39 {
  40         Oid                     relId;                  /* a relation identifier */
  41         Oid                     dbId;                   /* a database identifier */
  42 } LockRelId;
  43
  44 typedef struct LockInfoData
  45 {
  46         LockRelId       lockRelId;
  47 } LockInfoData;
  48
  49 typedef LockInfoData *LockInfo;
  50
  51 /*
  52  * Here are the contents of a relation cache entry.
  53  */
  54
  55 typedef struct RelationData
  56 {
  57         RelFileLocator rd_locator;      /* relation physical identifier */
  58         SMgrRelation rd_smgr;           /* cached file handle, or NULL */
  59         int                     rd_refcnt;              /* reference count */
  60         BackendId       rd_backend;             /* owning backend id, if temporary relation */
  61         bool            rd_islocaltemp; /* rel is a temp rel of this session */
  62         bool            rd_isnailed;    /* rel is nailed in cache */
  63         bool            rd_isvalid;             /* relcache entry is valid */
  64         bool            rd_indexvalid;  /* is rd_indexlist valid? (also rd_pkindex and
  65                                                                  * rd_replidindex) */
  66         bool            rd_statvalid;   /* is rd_statlist valid? */
  67
  68         /*----------
  69          * rd_createSubid is the ID of the highest subtransaction the rel has
  70          * survived into or zero if the rel or its storage was created before the
  71          * current top transaction.  (IndexStmt.oldNumber leads to the case of a new
  72          * rel with an old rd_locator.)  rd_firstRelfilelocatorSubid is the ID of the
  73          * highest subtransaction an rd_locator change has survived into or zero if
  74          * rd_locator matches the value it had at the start of the current top
  75          * transaction.  (Rolling back the subtransaction that
  76          * rd_firstRelfilelocatorSubid denotes would restore rd_locator to the value it
  77          * had at the start of the current top transaction.  Rolling back any
  78          * lower subtransaction would not.)  Their accuracy is critical to
  79          * RelationNeedsWAL().
  80          *
  81          * rd_newRelfilelocatorSubid is the ID of the highest subtransaction the
  82          * most-recent relfilenumber change has survived into or zero if not changed
  83          * in the current transaction (or we have forgotten changing it).  This
  84          * field is accurate when non-zero, but it can be zero when a relation has
  85          * multiple new relfilenumbers within a single transaction, with one of them
  86          * occurring in a subsequently aborted subtransaction, e.g.
  87          *              BEGIN;
  88          *              TRUNCATE t;
  89          *              SAVEPOINT save;
  90          *              TRUNCATE t;
  91          *              ROLLBACK TO save;
  92          *              -- rd_newRelfilelocatorSubid is now forgotten
  93          *
  94          * If every rd_*Subid field is zero, they are read-only outside
  95          * relcache.c.  Files that trigger rd_locator changes by updating
  96          * pg_class.reltablespace and/or pg_class.relfilenode call
  97          * RelationAssumeNewRelfilelocator() to update rd_*Subid.
  98          *
  99          * rd_droppedSubid is the ID of the highest subtransaction that a drop of
 100          * the rel has survived into.  In entries visible outside relcache.c, this
 101          * is always zero.
 102          */
 103         SubTransactionId rd_createSubid;        /* rel was created in current xact */
 104         SubTransactionId rd_newRelfilelocatorSubid; /* highest subxact changing
 105                                                                                                  * rd_locator to current value */
 106         SubTransactionId rd_firstRelfilelocatorSubid;   /* highest subxact
 107                                                                                                          * changing rd_locator to
 108                                                                                                          * any value */
 109         SubTransactionId rd_droppedSubid;       /* dropped with another Subid set */
 110
 111         Form_pg_class rd_rel;           /* RELATION tuple */
 112         TupleDesc       rd_att;                 /* tuple descriptor */
 113         Oid                     rd_id;                  /* relation's object id */
 114         LockInfoData rd_lockInfo;       /* lock mgr's info for locking relation */
 115         RuleLock   *rd_rules;           /* rewrite rules */
 116         MemoryContext rd_rulescxt;      /* private memory cxt for rd_rules, if any */
 117         TriggerDesc *trigdesc;          /* Trigger info, or NULL if rel has none */
 118         /* use "struct" here to avoid needing to include rowsecurity.h: */
 119         struct RowSecurityDesc *rd_rsdesc;      /* row security policies, or NULL */
 120
 121         /* data managed by RelationGetFKeyList: */
 122         List       *rd_fkeylist;        /* list of ForeignKeyCacheInfo (see below) */
 123         bool            rd_fkeyvalid;   /* true if list has been computed */
 124
 125         /* data managed by RelationGetPartitionKey: */
 126         PartitionKey rd_partkey;        /* partition key, or NULL */
 127         MemoryContext rd_partkeycxt;    /* private context for rd_partkey, if any */
 128
 129         /* data managed by RelationGetPartitionDesc: */
 130         PartitionDesc rd_partdesc;      /* partition descriptor, or NULL */
 131         MemoryContext rd_pdcxt;         /* private context for rd_partdesc, if any */
 132
 133         /* Same as above, for partdescs that omit detached partitions */
 134         PartitionDesc rd_partdesc_nodetached;   /* partdesc w/o detached parts */
 135         MemoryContext rd_pddcxt;        /* for rd_partdesc_nodetached, if any */
 136
 137         /*
 138          * pg_inherits.xmin of the partition that was excluded in
 139          * rd_partdesc_nodetached.  This informs a future user of that partdesc:
 140          * if this value is not in progress for the active snapshot, then the
 141          * partdesc can be used, otherwise they have to build a new one.  (This
 142          * matches what find_inheritance_children_extended would do).
 143          */
 144         TransactionId rd_partdesc_nodetached_xmin;
 145
 146         /* data managed by RelationGetPartitionQual: */
 147         List       *rd_partcheck;       /* partition CHECK quals */
 148         bool            rd_partcheckvalid;      /* true if list has been computed */
 149         MemoryContext rd_partcheckcxt;  /* private cxt for rd_partcheck, if any */
 150
 151         /* data managed by RelationGetIndexList: */
 152         List       *rd_indexlist;       /* list of OIDs of indexes on relation */
 153         Oid                     rd_pkindex;             /* OID of primary key, if any */
 154         Oid                     rd_replidindex; /* OID of replica identity index, if any */
 155
 156         /* data managed by RelationGetStatExtList: */
 157         List       *rd_statlist;        /* list of OIDs of extended stats */
 158
 159         /* data managed by RelationGetIndexAttrBitmap: */
 160         bool            rd_attrsvalid;  /* are bitmaps of attrs valid? */
 161         Bitmapset  *rd_keyattr;         /* cols that can be ref'd by foreign keys */
 162         Bitmapset  *rd_pkattr;          /* cols included in primary key */
 163         Bitmapset  *rd_idattr;          /* included in replica identity index */
 164         Bitmapset  *rd_hotblockingattr; /* cols blocking HOT update */
 165         Bitmapset  *rd_summarizedattr;  /* cols indexed by summarizing indexes */
 166
 167         PublicationDesc *rd_pubdesc;    /* publication descriptor, or NULL */
 168
 169         /*
 170          * rd_options is set whenever rd_rel is loaded into the relcache entry.
 171          * Note that you can NOT look into rd_rel for this data.  NULL means "use
 172          * defaults".
 173          */
 174         bytea      *rd_options;         /* parsed pg_class.reloptions */
 175
 176         /*
 177          * Oid of the handler for this relation. For an index this is a function
 178          * returning IndexAmRoutine, for table like relations a function returning
 179          * TableAmRoutine.  This is stored separately from rd_indam, rd_tableam as
 180          * its lookup requires syscache access, but during relcache bootstrap we
 181          * need to be able to initialize rd_tableam without syscache lookups.
 182          */
 183         Oid                     rd_amhandler;   /* OID of index AM's handler function */
 184
 185         /*
 186          * Table access method.
 187          */
 188         const struct TableAmRoutine *rd_tableam;
 189
 190         /* These are non-NULL only for an index relation: */
 191         Form_pg_index rd_index;         /* pg_index tuple describing this index */
 192         /* use "struct" here to avoid needing to include htup.h: */
 193         struct HeapTupleData *rd_indextuple;    /* all of pg_index tuple */
 194
 195         /*
 196          * index access support info (used only for an index relation)
 197          *
 198          * Note: only default support procs for each opclass are cached, namely
 199          * those with lefttype and righttype equal to the opclass's opcintype. The
 200          * arrays are indexed by support function number, which is a sufficient
 201          * identifier given that restriction.
 202          */
 203         MemoryContext rd_indexcxt;      /* private memory cxt for this stuff */
 204         /* use "struct" here to avoid needing to include amapi.h: */
 205         struct IndexAmRoutine *rd_indam;        /* index AM's API struct */
 206         Oid                *rd_opfamily;        /* OIDs of op families for each index col */
 207         Oid                *rd_opcintype;       /* OIDs of opclass declared input data types */
 208         RegProcedure *rd_support;       /* OIDs of support procedures */
 209         struct FmgrInfo *rd_supportinfo;        /* lookup info for support procedures */
 210         int16      *rd_indoption;       /* per-column AM-specific flags */
 211         List       *rd_indexprs;        /* index expression trees, if any */
 212         List       *rd_indpred;         /* index predicate tree, if any */
 213         Oid                *rd_exclops;         /* OIDs of exclusion operators, if any */
 214         Oid                *rd_exclprocs;       /* OIDs of exclusion ops' procs, if any */
 215         uint16     *rd_exclstrats;      /* exclusion ops' strategy numbers, if any */
 216         Oid                *rd_indcollation;    /* OIDs of index collations */
 217         bytea     **rd_opcoptions;      /* parsed opclass-specific options */
 218
 219         /*
 220          * rd_amcache is available for index and table AMs to cache private data
 221          * about the relation.  This must be just a cache since it may get reset
 222          * at any time (in particular, it will get reset by a relcache inval
 223          * message for the relation).  If used, it must point to a single memory
 224          * chunk palloc'd in CacheMemoryContext, or in rd_indexcxt for an index
 225          * relation.  A relcache reset will include freeing that chunk and setting
 226          * rd_amcache = NULL.
 227          */
 228         void       *rd_amcache;         /* available for use by index/table AM */
 229
 230         /*
 231          * foreign-table support
 232          *
 233          * rd_fdwroutine must point to a single memory chunk palloc'd in
 234          * CacheMemoryContext.  It will be freed and reset to NULL on a relcache
 235          * reset.
 236          */
 237
 238         /* use "struct" here to avoid needing to include fdwapi.h: */
 239         struct FdwRoutine *rd_fdwroutine;       /* cached function pointers, or NULL */
 240
 241         /*
 242          * Hack for CLUSTER, rewriting ALTER TABLE, etc: when writing a new
 243          * version of a table, we need to make any toast pointers inserted into it
 244          * have the existing toast table's OID, not the OID of the transient toast
 245          * table.  If rd_toastoid isn't InvalidOid, it is the OID to place in
 246          * toast pointers inserted into this rel.  (Note it's set on the new
 247          * version of the main heap, not the toast table itself.)  This also
 248          * causes toast_save_datum() to try to preserve toast value OIDs.
 249          */
 250         Oid                     rd_toastoid;    /* Real TOAST table's OID, or InvalidOid */
 251
 252         bool            pgstat_enabled; /* should relation stats be counted */
 253         /* use "struct" here to avoid needing to include pgstat.h: */
 254         struct PgStat_TableStatus *pgstat_info; /* statistics collection area */
 255 } RelationData;
 256
 257
 258 /*
 259  * ForeignKeyCacheInfo
 260  *              Information the relcache can cache about foreign key constraints
 261  *
 262  * This is basically just an image of relevant columns from pg_constraint.
 263  * We make it a subclass of Node so that copyObject() can be used on a list
 264  * of these, but we also ensure it is a "flat" object without substructure,
 265  * so that list_free_deep() is sufficient to free such a list.
 266  * The per-FK-column arrays can be fixed-size because we allow at most
 267  * INDEX_MAX_KEYS columns in a foreign key constraint.
 268  *
 269  * Currently, we mostly cache fields of interest to the planner, but the set
 270  * of fields has already grown the constraint OID for other uses.
 271  */
 272 typedef struct ForeignKeyCacheInfo
 273 {
 274         pg_node_attr(no_equal, no_read, no_query_jumble)
 275
 276         NodeTag         type;
 277         /* oid of the constraint itself */
 278         Oid                     conoid;
 279         /* relation constrained by the foreign key */
 280         Oid                     conrelid;
 281         /* relation referenced by the foreign key */
 282         Oid                     confrelid;
 283         /* number of columns in the foreign key */
 284         int                     nkeys;
 285
 286         /*
 287          * these arrays each have nkeys valid entries:
 288          */
 289         /* cols in referencing table */
 290         AttrNumber      conkey[INDEX_MAX_KEYS] pg_node_attr(array_size(nkeys));
 291         /* cols in referenced table */
 292         AttrNumber      confkey[INDEX_MAX_KEYS] pg_node_attr(array_size(nkeys));
 293         /* PK = FK operator OIDs */
 294         Oid                     conpfeqop[INDEX_MAX_KEYS] pg_node_attr(array_size(nkeys));
 295 } ForeignKeyCacheInfo;
 296
 297
 298 /*
 299  * StdRdOptions
 300  *              Standard contents of rd_options for heaps.
 301  *
 302  * RelationGetFillFactor() and RelationGetTargetPageFreeSpace() can only
 303  * be applied to relations that use this format or a superset for
 304  * private options data.
 305  */
 306  /* autovacuum-related reloptions. */
 307 typedef struct AutoVacOpts
 308 {
 309         bool            enabled;
 310         int                     vacuum_threshold;
 311         int                     vacuum_ins_threshold;
 312         int                     analyze_threshold;
 313         int                     vacuum_cost_limit;
 314         int                     freeze_min_age;
 315         int                     freeze_max_age;
 316         int                     freeze_table_age;
 317         int                     multixact_freeze_min_age;
 318         int                     multixact_freeze_max_age;
 319         int                     multixact_freeze_table_age;
 320         int                     log_min_duration;
 321         float8          vacuum_cost_delay;
 322         float8          vacuum_scale_factor;
 323         float8          vacuum_ins_scale_factor;
 324         float8          analyze_scale_factor;
 325 } AutoVacOpts;
 326
 327 /* StdRdOptions->vacuum_index_cleanup values */
 328 typedef enum StdRdOptIndexCleanup
 329 {
 330         STDRD_OPTION_VACUUM_INDEX_CLEANUP_AUTO = 0,
 331         STDRD_OPTION_VACUUM_INDEX_CLEANUP_OFF,
 332         STDRD_OPTION_VACUUM_INDEX_CLEANUP_ON
 333 } StdRdOptIndexCleanup;
 334
 335 typedef struct StdRdOptions
 336 {
 337         int32           vl_len_;                /* varlena header (do not touch directly!) */
 338         int                     fillfactor;             /* page fill factor in percent (0..100) */
 339         int                     toast_tuple_target; /* target for tuple toasting */
 340         AutoVacOpts autovacuum;         /* autovacuum-related options */
 341         bool            user_catalog_table; /* use as an additional catalog relation */
 342         int                     parallel_workers;       /* max number of parallel workers */
 343         StdRdOptIndexCleanup vacuum_index_cleanup;      /* controls index vacuuming */
 344         bool            vacuum_truncate;        /* enables vacuum to truncate a relation */
 345 } StdRdOptions;
 346
 347 #define HEAP_MIN_FILLFACTOR                     10
 348 #define HEAP_DEFAULT_FILLFACTOR         100
 349
 350 /*
 351  * RelationGetToastTupleTarget
 352  *              Returns the relation's toast_tuple_target.  Note multiple eval of argument!
 353  */
 354 #define RelationGetToastTupleTarget(relation, defaulttarg) \
 355         ((relation)->rd_options ? \
 356          ((StdRdOptions *) (relation)->rd_options)->toast_tuple_target : (defaulttarg))
 357
 358 /*
 359  * RelationGetFillFactor
 360  *              Returns the relation's fillfactor.  Note multiple eval of argument!
 361  */
 362 #define RelationGetFillFactor(relation, defaultff) \
 363         ((relation)->rd_options ? \
 364          ((StdRdOptions *) (relation)->rd_options)->fillfactor : (defaultff))
 365
 366 /*
 367  * RelationGetTargetPageUsage
 368  *              Returns the relation's desired space usage per page in bytes.
 369  */
 370 #define RelationGetTargetPageUsage(relation, defaultff) \
 371         (BLCKSZ * RelationGetFillFactor(relation, defaultff) / 100)
 372
 373 /*
 374  * RelationGetTargetPageFreeSpace
 375  *              Returns the relation's desired freespace per page in bytes.
 376  */
 377 #define RelationGetTargetPageFreeSpace(relation, defaultff) \
 378         (BLCKSZ * (100 - RelationGetFillFactor(relation, defaultff)) / 100)
 379
 380 /*
 381  * RelationIsUsedAsCatalogTable
 382  *              Returns whether the relation should be treated as a catalog table
 383  *              from the pov of logical decoding.  Note multiple eval of argument!
 384  */
 385 #define RelationIsUsedAsCatalogTable(relation)  \
 386         ((relation)->rd_options && \
 387          ((relation)->rd_rel->relkind == RELKIND_RELATION || \
 388           (relation)->rd_rel->relkind == RELKIND_MATVIEW) ? \
 389          ((StdRdOptions *) (relation)->rd_options)->user_catalog_table : false)
 390
 391 /*
 392  * RelationGetParallelWorkers
 393  *              Returns the relation's parallel_workers reloption setting.
 394  *              Note multiple eval of argument!
 395  */
 396 #define RelationGetParallelWorkers(relation, defaultpw) \
 397         ((relation)->rd_options ? \
 398          ((StdRdOptions *) (relation)->rd_options)->parallel_workers : (defaultpw))
 399
 400 /* ViewOptions->check_option values */
 401 typedef enum ViewOptCheckOption
 402 {
 403         VIEW_OPTION_CHECK_OPTION_NOT_SET,
 404         VIEW_OPTION_CHECK_OPTION_LOCAL,
 405         VIEW_OPTION_CHECK_OPTION_CASCADED
 406 } ViewOptCheckOption;
 407
 408 /*
 409  * ViewOptions
 410  *              Contents of rd_options for views
 411  */
 412 typedef struct ViewOptions
 413 {
 414         int32           vl_len_;                /* varlena header (do not touch directly!) */
 415         bool            security_barrier;
 416         bool            security_invoker;
 417         ViewOptCheckOption check_option;
 418 } ViewOptions;
 419
 420 /*
 421  * RelationIsSecurityView
 422  *              Returns whether the relation is security view, or not.  Note multiple
 423  *              eval of argument!
 424  */
 425 #define RelationIsSecurityView(relation)                                                                        \
 426         (AssertMacro(relation->rd_rel->relkind == RELKIND_VIEW),                                \
 427          (relation)->rd_options ?                                                                                               \
 428           ((ViewOptions *) (relation)->rd_options)->security_barrier : false)
 429
 430 /*
 431  * RelationHasSecurityInvoker
 432  *              Returns true if the relation has the security_invoker property set.
 433  *              Note multiple eval of argument!
 434  */
 435 #define RelationHasSecurityInvoker(relation)                                                            \
 436         (AssertMacro(relation->rd_rel->relkind == RELKIND_VIEW),                                \
 437          (relation)->rd_options ?                                                                                               \
 438           ((ViewOptions *) (relation)->rd_options)->security_invoker : false)
 439
 440 /*
 441  * RelationHasCheckOption
 442  *              Returns true if the relation is a view defined with either the local
 443  *              or the cascaded check option.  Note multiple eval of argument!
 444  */
 445 #define RelationHasCheckOption(relation)                                                                        \
 446         (AssertMacro(relation->rd_rel->relkind == RELKIND_VIEW),                                \
 447          (relation)->rd_options &&                                                                                              \
 448          ((ViewOptions *) (relation)->rd_options)->check_option !=                              \
 449          VIEW_OPTION_CHECK_OPTION_NOT_SET)
 450
 451 /*
 452  * RelationHasLocalCheckOption
 453  *              Returns true if the relation is a view defined with the local check
 454  *              option.  Note multiple eval of argument!
 455  */
 456 #define RelationHasLocalCheckOption(relation)                                                           \
 457         (AssertMacro(relation->rd_rel->relkind == RELKIND_VIEW),                                \
 458          (relation)->rd_options &&                                                                                              \
 459          ((ViewOptions *) (relation)->rd_options)->check_option ==                              \
 460          VIEW_OPTION_CHECK_OPTION_LOCAL)
 461
 462 /*
 463  * RelationHasCascadedCheckOption
 464  *              Returns true if the relation is a view defined with the cascaded check
 465  *              option.  Note multiple eval of argument!
 466  */
 467 #define RelationHasCascadedCheckOption(relation)                                                        \
 468         (AssertMacro(relation->rd_rel->relkind == RELKIND_VIEW),                                \
 469          (relation)->rd_options &&                                                                                              \
 470          ((ViewOptions *) (relation)->rd_options)->check_option ==                              \
 471           VIEW_OPTION_CHECK_OPTION_CASCADED)
 472
 473 /*
 474  * RelationIsValid
 475  *              True iff relation descriptor is valid.
 476  */
 477 #define RelationIsValid(relation) PointerIsValid(relation)
 478
 479 #define InvalidRelation ((Relation) NULL)
 480
 481 /*
 482  * RelationHasReferenceCountZero
 483  *              True iff relation reference count is zero.
 484  *
 485  * Note:
 486  *              Assumes relation descriptor is valid.
 487  */
 488 #define RelationHasReferenceCountZero(relation) \
 489                 ((bool)((relation)->rd_refcnt == 0))
 490
 491 /*
 492  * RelationGetForm
 493  *              Returns pg_class tuple for a relation.
 494  *
 495  * Note:
 496  *              Assumes relation descriptor is valid.
 497  */
 498 #define RelationGetForm(relation) ((relation)->rd_rel)
 499
 500 /*
 501  * RelationGetRelid
 502  *              Returns the OID of the relation
 503  */
 504 #define RelationGetRelid(relation) ((relation)->rd_id)
 505
 506 /*
 507  * RelationGetNumberOfAttributes
 508  *              Returns the total number of attributes in a relation.
 509  */
 510 #define RelationGetNumberOfAttributes(relation) ((relation)->rd_rel->relnatts)
 511
 512 /*
 513  * IndexRelationGetNumberOfAttributes
 514  *              Returns the number of attributes in an index.
 515  */
 516 #define IndexRelationGetNumberOfAttributes(relation) \
 517                 ((relation)->rd_index->indnatts)
 518
 519 /*
 520  * IndexRelationGetNumberOfKeyAttributes
 521  *              Returns the number of key attributes in an index.
 522  */
 523 #define IndexRelationGetNumberOfKeyAttributes(relation) \
 524                 ((relation)->rd_index->indnkeyatts)
 525
 526 /*
 527  * RelationGetDescr
 528  *              Returns tuple descriptor for a relation.
 529  */
 530 #define RelationGetDescr(relation) ((relation)->rd_att)
 531
 532 /*
 533  * RelationGetRelationName
 534  *              Returns the rel's name.
 535  *
 536  * Note that the name is only unique within the containing namespace.
 537  */
 538 #define RelationGetRelationName(relation) \
 539         (NameStr((relation)->rd_rel->relname))
 540
 541 /*
 542  * RelationGetNamespace
 543  *              Returns the rel's namespace OID.
 544  */
 545 #define RelationGetNamespace(relation) \
 546         ((relation)->rd_rel->relnamespace)
 547
 548 /*
 549  * RelationIsMapped
 550  *              True if the relation uses the relfilenumber map.  Note multiple eval
 551  *              of argument!
 552  */
 553 #define RelationIsMapped(relation) \
 554         (RELKIND_HAS_STORAGE((relation)->rd_rel->relkind) && \
 555          ((relation)->rd_rel->relfilenode == InvalidRelFileNumber))
 556
 557 #ifndef FRONTEND
 558 /*
 559  * RelationGetSmgr
 560  *              Returns smgr file handle for a relation, opening it if needed.
 561  *
 562  * Very little code is authorized to touch rel->rd_smgr directly.  Instead
 563  * use this function to fetch its value.
 564  *
 565  * Note: since a relcache flush can cause the file handle to be closed again,
 566  * it's unwise to hold onto the pointer returned by this function for any
 567  * long period.  Recommended practice is to just re-execute RelationGetSmgr
 568  * each time you need to access the SMgrRelation.  It's quite cheap in
 569  * comparison to whatever an smgr function is going to do.
 570  */
 571 static inline SMgrRelation
 572 RelationGetSmgr(Relation rel)
 573 {
 574         if (unlikely(rel->rd_smgr == NULL))
 575                 smgrsetowner(&(rel->rd_smgr), smgropen(rel->rd_locator, rel->rd_backend));
 576         return rel->rd_smgr;
 577 }
 578
 579 /*
 580  * RelationCloseSmgr
 581  *              Close the relation at the smgr level, if not already done.
 582  */
 583 static inline void
 584 RelationCloseSmgr(Relation relation)
 585 {
 586         if (relation->rd_smgr != NULL)
 587                 smgrclose(relation->rd_smgr);
 588
 589         /* smgrclose should unhook from owner pointer */
 590         Assert(relation->rd_smgr == NULL);
 591 }
 592 #endif                                                  /* !FRONTEND */
 593
 594 /*
 595  * RelationGetTargetBlock
 596  *              Fetch relation's current insertion target block.
 597  *
 598  * Returns InvalidBlockNumber if there is no current target block.  Note
 599  * that the target block status is discarded on any smgr-level invalidation,
 600  * so there's no need to re-open the smgr handle if it's not currently open.
 601  */
 602 #define RelationGetTargetBlock(relation) \
 603         ( (relation)->rd_smgr != NULL ? (relation)->rd_smgr->smgr_targblock : InvalidBlockNumber )
 604
 605 /*
 606  * RelationSetTargetBlock
 607  *              Set relation's current insertion target block.
 608  */
 609 #define RelationSetTargetBlock(relation, targblock) \
 610         do { \
 611                 RelationGetSmgr(relation)->smgr_targblock = (targblock); \
 612         } while (0)
 613
 614 /*
 615  * RelationIsPermanent
 616  *              True if relation is permanent.
 617  */
 618 #define RelationIsPermanent(relation) \
 619         ((relation)->rd_rel->relpersistence == RELPERSISTENCE_PERMANENT)
 620
 621 /*
 622  * RelationNeedsWAL
 623  *              True if relation needs WAL.
 624  *
 625  * Returns false if wal_level = minimal and this relation is created or
 626  * truncated in the current transaction.  See "Skipping WAL for New
 627  * RelFileLocator" in src/backend/access/transam/README.
 628  */
 629 #define RelationNeedsWAL(relation)                                                                              \
 630         (RelationIsPermanent(relation) && (XLogIsNeeded() ||                            \
 631           (relation->rd_createSubid == InvalidSubTransactionId &&                       \
 632            relation->rd_firstRelfilelocatorSubid == InvalidSubTransactionId)))
 633
 634 /*
 635  * RelationUsesLocalBuffers
 636  *              True if relation's pages are stored in local buffers.
 637  */
 638 #define RelationUsesLocalBuffers(relation) \
 639         ((relation)->rd_rel->relpersistence == RELPERSISTENCE_TEMP)
 640
 641 /*
 642  * RELATION_IS_LOCAL
 643  *              If a rel is either temp or newly created in the current transaction,
 644  *              it can be assumed to be accessible only to the current backend.
 645  *              This is typically used to decide that we can skip acquiring locks.
 646  *
 647  * Beware of multiple eval of argument
 648  */
 649 #define RELATION_IS_LOCAL(relation) \
 650         ((relation)->rd_islocaltemp || \
 651          (relation)->rd_createSubid != InvalidSubTransactionId)
 652
 653 /*
 654  * RELATION_IS_OTHER_TEMP
 655  *              Test for a temporary relation that belongs to some other session.
 656  *
 657  * Beware of multiple eval of argument
 658  */
 659 #define RELATION_IS_OTHER_TEMP(relation) \
 660         ((relation)->rd_rel->relpersistence == RELPERSISTENCE_TEMP && \
 661          !(relation)->rd_islocaltemp)
 662
 663
 664 /*
 665  * RelationIsScannable
 666  *              Currently can only be false for a materialized view which has not been
 667  *              populated by its query.  This is likely to get more complicated later,
 668  *              so use a macro which looks like a function.
 669  */
 670 #define RelationIsScannable(relation) ((relation)->rd_rel->relispopulated)
 671
 672 /*
 673  * RelationIsPopulated
 674  *              Currently, we don't physically distinguish the "populated" and
 675  *              "scannable" properties of matviews, but that may change later.
 676  *              Hence, use the appropriate one of these macros in code tests.
 677  */
 678 #define RelationIsPopulated(relation) ((relation)->rd_rel->relispopulated)
 679
 680 /*
 681  * RelationIsAccessibleInLogicalDecoding
 682  *              True if we need to log enough information to have access via
 683  *              decoding snapshot.
 684  */
 685 #define RelationIsAccessibleInLogicalDecoding(relation) \
 686         (XLogLogicalInfoActive() && \
 687          RelationNeedsWAL(relation) && \
 688          (IsCatalogRelation(relation) || RelationIsUsedAsCatalogTable(relation)))
 689
 690 /*
 691  * RelationIsLogicallyLogged
 692  *              True if we need to log enough information to extract the data from the
 693  *              WAL stream.
 694  *
 695  * We don't log information for unlogged tables (since they don't WAL log
 696  * anyway), for foreign tables (since they don't WAL log, either),
 697  * and for system tables (their content is hard to make sense of, and
 698  * it would complicate decoding slightly for little gain). Note that we *do*
 699  * log information for user defined catalog tables since they presumably are
 700  * interesting to the user...
 701  */
 702 #define RelationIsLogicallyLogged(relation) \
 703         (XLogLogicalInfoActive() && \
 704          RelationNeedsWAL(relation) && \
 705          (relation)->rd_rel->relkind != RELKIND_FOREIGN_TABLE &&        \
 706          !IsCatalogRelation(relation))
 707
 708 /* routines in utils/cache/relcache.c */
 709 extern void RelationIncrementReferenceCount(Relation rel);
 710 extern void RelationDecrementReferenceCount(Relation rel);
 711
 712 #endif                                                  /* REL_H */