3 * This is the IBM DB2 database abstraction layer.
4 * See maintenance/ibm_db2/README for development notes
5 * and other specific information
9 * @author leo.petr+mediawiki@gmail.com
13 * This represents a column in a DB2 database
16 class IBM_DB2Field
implements Field
{
18 private $tablename = '';
20 private $nullable = false;
21 private $max_length = 0;
24 * Builder method for the class
25 * @param $db DatabaseIbm_db2: Database interface
26 * @param $table String: table name
27 * @param $field String: column name
28 * @return IBM_DB2Field
30 static function fromText( $db, $table, $field ) {
35 lcase( coltype ) AS typname,
36 nulls AS attnotnull, length AS attlen
37 FROM sysibm.syscolumns
38 WHERE tbcreator=%s AND tbname=%s AND name=%s;
42 $db->addQuotes( $wgDBmwschema ),
43 $db->addQuotes( $table ),
44 $db->addQuotes( $field )
47 $row = $db->fetchObject( $res );
51 $n = new IBM_DB2Field
;
52 $n->type
= $row->typname
;
53 $n->nullable
= ( $row->attnotnull
== 'N' );
55 $n->tablename
= $table;
56 $n->max_length
= $row->attlen
;
61 * @return string column name
63 function name() { return $this->name
; }
66 * @return string table name
68 function tableName() { return $this->tablename
; }
71 * @return string column type
73 function type() { return $this->type
; }
76 * @return bool true or false
78 function isNullable() { return $this->nullable
; }
80 * How much can you fit in the column per row?
83 function maxLength() { return $this->max_length
; }
87 * Wrapper around binary large objects
93 public function __construct( $data ) {
97 public function getData() {
101 public function __toString() {
107 * Primary database interface
110 class DatabaseIbm_db2
extends DatabaseBase
{
113 protected $mLastQuery = '';
114 protected $mPHPError = false;
116 protected $mServer, $mUser, $mPassword, $mConn = null, $mDBname;
117 protected $mOpened = false;
119 protected $mTablePrefix;
121 protected $mTrxLevel = 0;
122 protected $mErrorCount = 0;
123 protected $mLBInfo = array();
124 protected $mFakeSlaveLag = null, $mFakeMaster = false;
128 /** Database server port */
129 protected $mPort = null;
130 /** Schema for tables, stored procedures, triggers */
131 protected $mSchema = null;
132 /** Whether the schema has been applied in this session */
133 protected $mSchemaSet = false;
134 /** Result of last query */
135 protected $mLastResult = null;
136 /** Number of rows affected by last INSERT/UPDATE/DELETE */
137 protected $mAffectedRows = null;
138 /** Number of rows returned by last SELECT */
139 protected $mNumRows = null;
141 /** Connection config options - see constructor */
142 public $mConnOptions = array();
143 /** Statement config options -- see constructor */
144 public $mStmtOptions = array();
146 /** Default schema */
147 const USE_GLOBAL
= 'get from global';
149 /** Option that applies to nothing */
150 const NONE_OPTION
= 0x00;
151 /** Option that applies to connection objects */
152 const CONN_OPTION
= 0x01;
153 /** Option that applies to statement objects */
154 const STMT_OPTION
= 0x02;
156 /** Regular operation mode -- minimal debug messages */
157 const REGULAR_MODE
= 'regular';
158 /** Installation mode -- lots of debug messages */
159 const INSTALL_MODE
= 'install';
161 /** Controls the level of debug message output */
162 protected $mMode = self
::REGULAR_MODE
;
164 /** Last sequence value used for a primary key */
165 protected $mInsertId = null;
167 ######################################
168 # Getters and Setters
169 ######################################
172 * Returns true if this database supports (and uses) cascading deletes
174 function cascadingDeletes() {
179 * Returns true if this database supports (and uses) triggers (e.g. on the
182 function cleanupTriggers() {
187 * Returns true if this database is strict about what can be put into an
189 * Specifically, it uses a NULL value instead of an empty string.
191 function strictIPs() {
196 * Returns true if this database uses timestamps rather than integers
198 function realTimestamps() {
203 * Returns true if this database does an implicit sort when doing GROUP BY
205 function implicitGroupby() {
210 * Returns true if this database does an implicit order by when the column
212 * For example: SELECT page_title FROM page LIMIT 1
214 function implicitOrderby() {
219 * Returns true if this database can do a native search on IP columns
220 * e.g. this works as expected: .. WHERE rc_ip = '127.42.12.102/32';
222 function searchableIPs() {
227 * Returns true if this database can use functional indexes
229 function functionalIndexes() {
234 * Returns a unique string representing the wiki on the server
236 function getWikiID() {
237 if( $this->mSchema
) {
238 return "{$this->mDBname}-{$this->mSchema}";
240 return $this->mDBname
;
250 * @param $server String: hostname of database server
251 * @param $user String: username
252 * @param $password String: password
253 * @param $dbName String: database name on the server
254 * @param $flags Integer: database behaviour flags (optional, unused)
255 * @param $schema String
257 public function __construct( $server = false, $user = false,
259 $dbName = false, $flags = 0,
260 $schema = self
::USE_GLOBAL
)
262 global $wgDBmwschema;
264 if ( $schema == self
::USE_GLOBAL
) {
265 $this->mSchema
= $wgDBmwschema;
267 $this->mSchema
= $schema;
270 // configure the connection and statement objects
272 $this->setDB2Option( 'cursor', 'DB2_SCROLLABLE',
273 self::CONN_OPTION | self::STMT_OPTION );
275 $this->setDB2Option( 'db2_attr_case', 'DB2_CASE_LOWER',
276 self
::CONN_OPTION | self
::STMT_OPTION
);
277 $this->setDB2Option( 'deferred_prepare', 'DB2_DEFERRED_PREPARE_ON',
279 $this->setDB2Option( 'rowcount', 'DB2_ROWCOUNT_PREFETCH_ON',
282 parent
::__construct( $server, $user, $password, $dbName, DBO_TRX |
$flags );
286 * Enables options only if the ibm_db2 extension version supports them
287 * @param $name String: name of the option in the options array
288 * @param $const String: name of the constant holding the right option value
289 * @param $type Integer: whether this is a Connection or Statement otion
291 private function setDB2Option( $name, $const, $type ) {
292 if ( defined( $const ) ) {
293 if ( $type & self
::CONN_OPTION
) {
294 $this->mConnOptions
[$name] = constant( $const );
296 if ( $type & self
::STMT_OPTION
) {
297 $this->mStmtOptions
[$name] = constant( $const );
301 "$const is not defined. ibm_db2 version is likely too low." );
306 * Outputs debug information in the appropriate place
307 * @param $string String: the relevant debug message
309 private function installPrint( $string ) {
310 wfDebug( "$string\n" );
311 if ( $this->mMode
== self
::INSTALL_MODE
) {
312 print "<li><pre>$string</pre></li>";
318 * Opens a database connection and returns it
319 * Closes any existing connection
321 * @param $server String: hostname
322 * @param $user String
323 * @param $password String
324 * @param $dbName String: database name
325 * @return a fresh connection
327 public function open( $server, $user, $password, $dbName ) {
328 wfProfileIn( __METHOD__
);
330 # Load IBM DB2 driver if missing
333 # Test for IBM DB2 support, to avoid suppressed fatal error
334 if ( !function_exists( 'db2_connect' ) ) {
335 throw new DBConnectionError( $this, "DB2 functions missing, have you enabled the ibm_db2 extension for PHP?" );
340 // Close existing connection
343 $this->mServer
= $server;
344 $this->mPort
= $port = $wgDBport;
345 $this->mUser
= $user;
346 $this->mPassword
= $password;
347 $this->mDBname
= $dbName;
349 $this->openUncataloged( $dbName, $user, $password, $server, $port );
351 if ( !$this->mConn
) {
352 $this->installPrint( "DB connection error\n" );
354 "Server: $server, Database: $dbName, User: $user, Password: "
355 . substr( $password, 0, 3 ) . "...\n" );
356 $this->installPrint( $this->lastError() . "\n" );
357 wfProfileOut( __METHOD__
);
358 wfDebug( "DB connection error\n" );
359 wfDebug( "Server: $server, Database: $dbName, User: $user, Password: " . substr( $password, 0, 3 ) . "...\n" );
360 wfDebug( $this->lastError() . "\n" );
361 throw new DBConnectionError( $this, $this->lastError() );
364 // Apply connection config
365 db2_set_option( $this->mConn
, $this->mConnOptions
, 1 );
366 // Some MediaWiki code is still transaction-less (?).
367 // The strategy is to keep AutoCommit on for that code
368 // but switch it off whenever a transaction is begun.
369 db2_autocommit( $this->mConn
, DB2_AUTOCOMMIT_ON
);
371 $this->mOpened
= true;
372 $this->applySchema();
374 wfProfileOut( __METHOD__
);
379 * Opens a cataloged database connection, sets mConn
381 protected function openCataloged( $dbName, $user, $password ) {
382 wfSuppressWarnings();
383 $this->mConn
= db2_pconnect( $dbName, $user, $password );
388 * Opens an uncataloged database connection, sets mConn
390 protected function openUncataloged( $dbName, $user, $password, $server, $port )
392 $dsn = "DRIVER={IBM DB2 ODBC DRIVER};DATABASE=$dbName;CHARSET=UTF-8;HOSTNAME=$server;PORT=$port;PROTOCOL=TCPIP;UID=$user;PWD=$password;";
393 wfSuppressWarnings();
394 $this->mConn
= db2_pconnect($dsn, "", "", array());
399 * Closes a database connection, if it is open
400 * Returns success, true if already closed
402 public function close() {
403 $this->mOpened
= false;
404 if ( $this->mConn
) {
405 if ( $this->trxLevel() > 0 ) {
408 return db2_close( $this->mConn
);
415 * Retrieves the most current database error
416 * Forces a database rollback
418 public function lastError() {
419 $connerr = db2_conn_errormsg();
424 $stmterr = db2_stmt_errormsg();
434 * Get the last error number
435 * Return 0 if no error
438 public function lastErrno() {
439 $connerr = db2_conn_error();
443 $stmterr = db2_stmt_error();
451 * Is a database connection open?
454 public function isOpen() { return $this->mOpened
; }
457 * The DBMS-dependent part of query()
458 * @param $sql String: SQL query.
459 * @return object Result object for fetch functions or false on failure
461 protected function doQuery( $sql ) {
462 $this->applySchema();
464 // Needed to handle any UTF-8 encoding issues in the raw sql
465 // Note that we fully support prepared statements for DB2
466 // prepare() and execute() should be used instead of doQuery() whenever possible
467 $sql = utf8_decode($sql);
469 $ret = db2_exec( $this->mConn
, $sql, $this->mStmtOptions
);
470 if( $ret == false ) {
471 $error = db2_stmt_errormsg();
473 $this->installPrint( "<pre>$sql</pre>" );
474 $this->installPrint( $error );
475 throw new DBUnexpectedError( $this, 'SQL error: '
476 . htmlspecialchars( $error ) );
478 $this->mLastResult
= $ret;
479 $this->mAffectedRows
= null; // Not calculated until asked for
484 * @return string Version information from the database
486 public function getServerVersion() {
487 $info = db2_server_info( $this->mConn
);
488 return $info->DBMS_VER
;
492 * Queries whether a given table exists
495 public function tableExists( $table ) {
496 $schema = $this->mSchema
;
498 $sql = "SELECT COUNT( * ) FROM SYSIBM.SYSTABLES ST WHERE ST.NAME = '" .
499 strtoupper( $table ) .
500 "' AND ST.CREATOR = '" .
501 strtoupper( $schema ) . "'";
502 $res = $this->query( $sql );
507 // If the table exists, there should be one of it
508 $row = $this->fetchRow( $res );
510 if ( $count == '1' ||
$count == 1 ) {
518 * Fetch the next row from the given result object, in object form.
519 * Fields can be retrieved with $row->fieldname, with fields acting like
522 * @param $res SQL result object as returned from Database::query(), etc.
523 * @return DB2 row object
524 * @throws DBUnexpectedError Thrown if the database returns an error
526 public function fetchObject( $res ) {
527 if ( $res instanceof ResultWrapper
) {
530 wfSuppressWarnings();
531 $row = db2_fetch_object( $res );
533 if( $this->lastErrno() ) {
534 throw new DBUnexpectedError( $this, 'Error in fetchObject(): '
535 . htmlspecialchars( $this->lastError() ) );
541 * Fetch the next row from the given result object, in associative array
542 * form. Fields are retrieved with $row['fieldname'].
544 * @param $res SQL result object as returned from Database::query(), etc.
545 * @return DB2 row object
546 * @throws DBUnexpectedError Thrown if the database returns an error
548 public function fetchRow( $res ) {
549 if ( $res instanceof ResultWrapper
) {
552 if ( db2_num_rows( $res ) > 0) {
553 wfSuppressWarnings();
554 $row = db2_fetch_array( $res );
556 if ( $this->lastErrno() ) {
557 throw new DBUnexpectedError( $this, 'Error in fetchRow(): '
558 . htmlspecialchars( $this->lastError() ) );
567 * Doesn't escape numbers
569 * @param $s String: string to escape
570 * @return escaped string
572 public function addQuotes( $s ) {
573 //$this->installPrint( "DB2::addQuotes( $s )\n" );
574 if ( is_null( $s ) ) {
576 } elseif ( $s instanceof Blob
) {
577 return "'" . $s->fetch( $s ) . "'";
578 } elseif ( $s instanceof IBM_DB2Blob
) {
579 return "'" . $this->decodeBlob( $s ) . "'";
581 $s = $this->strencode( $s );
582 if ( is_numeric( $s ) ) {
590 * Verifies that a DB2 column/field type is numeric
592 * @param $type String: DB2 column type
593 * @return Boolean: true if numeric
595 public function is_numeric_type( $type ) {
596 switch ( strtoupper( $type ) ) {
611 * Alias for addQuotes()
612 * @param $s String: string to escape
613 * @return escaped string
615 public function strencode( $s ) {
616 // Bloody useless function
617 // Prepends backslashes to \x00, \n, \r, \, ', " and \x1a.
618 // But also necessary
619 $s = db2_escape_string( $s );
620 // Wide characters are evil -- some of them look like '
621 $s = utf8_encode( $s );
623 $from = array( "\\\\", "\\'", '\\n', '\\t', '\\"', '\\r' );
624 $to = array( "\\", "''", "\n", "\t", '"', "\r" );
625 $s = str_replace( $from, $to, $s ); // DB2 expects '', not \' escaping
630 * Switch into the database schema
632 protected function applySchema() {
633 if ( !( $this->mSchemaSet
) ) {
634 $this->mSchemaSet
= true;
636 $this->doQuery( "SET SCHEMA = $this->mSchema" );
642 * Start a transaction (mandatory)
644 public function begin( $fname = 'DatabaseIbm_db2::begin' ) {
645 // BEGIN is implicit for DB2
646 // However, it requires that AutoCommit be off.
648 // Some MediaWiki code is still transaction-less (?).
649 // The strategy is to keep AutoCommit on for that code
650 // but switch it off whenever a transaction is begun.
651 db2_autocommit( $this->mConn
, DB2_AUTOCOMMIT_OFF
);
653 $this->mTrxLevel
= 1;
658 * Must have a preceding begin()
660 public function commit( $fname = 'DatabaseIbm_db2::commit' ) {
661 db2_commit( $this->mConn
);
663 // Some MediaWiki code is still transaction-less (?).
664 // The strategy is to keep AutoCommit on for that code
665 // but switch it off whenever a transaction is begun.
666 db2_autocommit( $this->mConn
, DB2_AUTOCOMMIT_ON
);
668 $this->mTrxLevel
= 0;
672 * Cancel a transaction
674 public function rollback( $fname = 'DatabaseIbm_db2::rollback' ) {
675 db2_rollback( $this->mConn
);
676 // turn auto-commit back on
677 // not sure if this is appropriate
678 db2_autocommit( $this->mConn
, DB2_AUTOCOMMIT_ON
);
679 $this->mTrxLevel
= 0;
683 * Makes an encoded list of strings from an array
685 * LIST_COMMA - comma separated, no field names
686 * LIST_AND - ANDed WHERE clause (without the WHERE)
687 * LIST_OR - ORed WHERE clause (without the WHERE)
688 * LIST_SET - comma separated with field names, like a SET clause
689 * LIST_NAMES - comma separated field names
690 * LIST_SET_PREPARED - like LIST_SET, except with ? tokens as values
692 function makeList( $a, $mode = LIST_COMMA
) {
693 if ( !is_array( $a ) ) {
694 throw new DBUnexpectedError( $this,
695 'DatabaseIbm_db2::makeList called with incorrect parameters' );
698 // if this is for a prepared UPDATE statement
699 // (this should be promoted to the parent class
700 // once other databases use prepared statements)
701 if ( $mode == LIST_SET_PREPARED
) {
704 foreach ( $a as $field => $value ) {
706 $list .= ", $field = ?";
708 $list .= "$field = ?";
717 // otherwise, call the usual function
718 return parent
::makeList( $a, $mode );
722 * Construct a LIMIT query with optional offset
723 * This is used for query pages
725 * @param $sql string SQL query we will append the limit too
726 * @param $limit integer the SQL limit
727 * @param $offset integer the SQL offset (default false)
729 public function limitResult( $sql, $limit, $offset=false ) {
730 if( !is_numeric( $limit ) ) {
731 throw new DBUnexpectedError( $this,
732 "Invalid non-numeric limit passed to limitResult()\n" );
735 if ( stripos( $sql, 'where' ) === false ) {
736 return "$sql AND ( ROWNUM BETWEEN $offset AND $offset+$limit )";
738 return "$sql WHERE ( ROWNUM BETWEEN $offset AND $offset+$limit )";
741 return "$sql FETCH FIRST $limit ROWS ONLY ";
745 * Handle reserved keyword replacement in table names
747 * @param $name Object
748 * @param $name Boolean
751 public function tableName( $name, $format = 'quoted' ) {
752 // we want maximum compatibility with MySQL schema
757 * Generates a timestamp in an insertable format
759 * @param $ts timestamp
760 * @return String: timestamp value
762 public function timestamp( $ts = 0 ) {
763 // TS_MW cannot be easily distinguished from an integer
764 return wfTimestamp( TS_DB2
, $ts );
768 * Return the next in a sequence, save the value for retrieval via insertId()
769 * @param $seqName String: name of a defined sequence in the database
770 * @return next value in that sequence
772 public function nextSequenceValue( $seqName ) {
773 // Not using sequences in the primary schema to allow for easier migration
775 // Emulating MySQL behaviour of using NULL to signal that sequences
778 $safeseq = preg_replace( "/'/", "''", $seqName );
779 $res = $this->query( "VALUES NEXTVAL FOR $safeseq" );
780 $row = $this->fetchRow( $res );
781 $this->mInsertId = $row[0];
782 return $this->mInsertId;
788 * This must be called after nextSequenceVal
789 * @return Last sequence value used as a primary key
791 public function insertId() {
792 return $this->mInsertId
;
796 * Updates the mInsertId property with the value of the last insert
797 * into a generated column
799 * @param $table String: sanitized table name
800 * @param $primaryKey Mixed: string name of the primary key
801 * @param $stmt Resource: prepared statement resource
802 * of the SELECT primary_key FROM FINAL TABLE ( INSERT ... ) form
804 private function calcInsertId( $table, $primaryKey, $stmt ) {
806 $this->mInsertId
= db2_last_insert_id( $this->mConn
);
811 * INSERT wrapper, inserts an array into a table
813 * $args may be a single associative array, or an array of arrays
814 * with numeric keys, for multi-row insert
816 * @param $table String: Name of the table to insert to.
817 * @param $args Array: Items to insert into the table.
818 * @param $fname String: Name of the function, for profiling
819 * @param $options String or Array. Valid options: IGNORE
821 * @return bool Success of insert operation. IGNORE always returns true.
823 public function insert( $table, $args, $fname = 'DatabaseIbm_db2::insert',
826 if ( !count( $args ) ) {
829 // get database-specific table name (not used)
830 $table = $this->tableName( $table );
831 // format options as an array
832 $options = IBM_DB2Helper
::makeArray( $options );
833 // format args as an array of arrays
834 if ( !( isset( $args[0] ) && is_array( $args[0] ) ) ) {
835 $args = array( $args );
838 // prevent insertion of NULL into primary key columns
839 list( $args, $primaryKeys ) = $this->removeNullPrimaryKeys( $table, $args );
840 // if there's only one primary key
841 // we'll be able to read its value after insertion
843 if ( count( $primaryKeys ) == 1 ) {
844 $primaryKey = $primaryKeys[0];
848 $keys = array_keys( $args[0] );
849 $key_count = count( $keys );
851 // If IGNORE is set, we use savepoints to emulate mysql's behavior
852 $ignore = in_array( 'IGNORE', $options ) ?
'mw' : '';
856 // If we are not in a transaction, we need to be for savepoint trickery
857 if ( !$this->mTrxLevel
) {
861 $sql = "INSERT INTO $table ( " . implode( ',', $keys ) . ' ) VALUES ';
862 if ( $key_count == 1 ) {
865 $sql .= '( ?' . str_repeat( ',?', $key_count-1 ) . ' )';
867 $this->installPrint( "Preparing the following SQL:" );
868 $this->installPrint( "$sql" );
869 $this->installPrint( print_r( $args, true ));
870 $stmt = $this->prepare( $sql );
872 // start a transaction/enter transaction mode
877 foreach ( $args as $row ) {
878 //$this->installPrint( "Inserting " . print_r( $row, true ));
879 // insert each row into the database
880 $res = $res & $this->execute( $stmt, $row );
882 $this->installPrint( 'Last error:' );
883 $this->installPrint( $this->lastError() );
885 // get the last inserted value into a generated column
886 $this->calcInsertId( $table, $primaryKey, $stmt );
889 $olde = error_reporting( 0 );
890 // For future use, we may want to track the number of actual inserts
891 // Right now, insert (all writes) simply return true/false
892 $numrowsinserted = 0;
894 // always return true
897 foreach ( $args as $row ) {
898 $overhead = "SAVEPOINT $ignore ON ROLLBACK RETAIN CURSORS";
899 db2_exec( $this->mConn
, $overhead, $this->mStmtOptions
);
901 $res2 = $this->execute( $stmt, $row );
904 $this->installPrint( 'Last error:' );
905 $this->installPrint( $this->lastError() );
907 // get the last inserted value into a generated column
908 $this->calcInsertId( $table, $primaryKey, $stmt );
910 $errNum = $this->lastErrno();
912 db2_exec( $this->mConn
, "ROLLBACK TO SAVEPOINT $ignore",
913 $this->mStmtOptions
);
915 db2_exec( $this->mConn
, "RELEASE SAVEPOINT $ignore",
916 $this->mStmtOptions
);
921 $olde = error_reporting( $olde );
922 // Set the affected row count for the whole operation
923 $this->mAffectedRows
= $numrowsinserted;
927 $this->freePrepared( $stmt );
933 * Given a table name and a hash of columns with values
934 * Removes primary key columns from the hash where the value is NULL
936 * @param $table String: name of the table
937 * @param $args Array of hashes of column names with values
938 * @return Array: tuple( filtered array of columns, array of primary keys )
940 private function removeNullPrimaryKeys( $table, $args ) {
941 $schema = $this->mSchema
;
943 // find out the primary keys
944 $keyres = $this->doQuery( "SELECT NAME FROM SYSIBM.SYSCOLUMNS WHERE TBNAME = '"
945 . strtoupper( $table )
946 . "' AND TBCREATOR = '"
947 . strtoupper( $schema )
948 . "' AND KEYSEQ > 0" );
952 $row = $this->fetchRow( $keyres );
954 $row = $this->fetchRow( $keyres )
957 $keys[] = strtolower( $row[0] );
959 // remove primary keys
960 foreach ( $args as $ai => $row ) {
961 foreach ( $keys as $key ) {
962 if ( $row[$key] == null ) {
968 // return modified hash
969 return array( $args, $keys );
973 * UPDATE wrapper, takes a condition array and a SET array
975 * @param $table String: The table to UPDATE
976 * @param $values An array of values to SET
977 * @param $conds An array of conditions ( WHERE ). Use '*' to update all rows.
978 * @param $fname String: The Class::Function calling this function
980 * @param $options An array of UPDATE options, can be one or
981 * more of IGNORE, LOW_PRIORITY
984 public function update( $table, $values, $conds, $fname = 'DatabaseIbm_db2::update',
987 $table = $this->tableName( $table );
988 $opts = $this->makeUpdateOptions( $options );
989 $sql = "UPDATE $opts $table SET "
990 . $this->makeList( $values, LIST_SET_PREPARED
);
991 if ( $conds != '*' ) {
992 $sql .= " WHERE " . $this->makeList( $conds, LIST_AND
);
994 $stmt = $this->prepare( $sql );
995 $this->installPrint( 'UPDATE: ' . print_r( $values, true ) );
996 // assuming for now that an array with string keys will work
997 // if not, convert to simple array first
998 $result = $this->execute( $stmt, $values );
999 $this->freePrepared( $stmt );
1005 * DELETE query wrapper
1007 * Use $conds == "*" to delete all rows
1009 public function delete( $table, $conds, $fname = 'DatabaseIbm_db2::delete' ) {
1011 throw new DBUnexpectedError( $this,
1012 'DatabaseIbm_db2::delete() called with no conditions' );
1014 $table = $this->tableName( $table );
1015 $sql = "DELETE FROM $table";
1016 if ( $conds != '*' ) {
1017 $sql .= ' WHERE ' . $this->makeList( $conds, LIST_AND
);
1019 $result = $this->query( $sql, $fname );
1025 * Returns the number of rows affected by the last query or 0
1026 * @return Integer: the number of rows affected by the last query
1028 public function affectedRows() {
1029 if ( !is_null( $this->mAffectedRows
) ) {
1030 // Forced result for simulated queries
1031 return $this->mAffectedRows
;
1033 if( empty( $this->mLastResult
) ) {
1036 return db2_num_rows( $this->mLastResult
);
1040 * Returns the number of rows in the result set
1041 * Has to be called right after the corresponding select query
1042 * @param $res Object result set
1043 * @return Integer: number of rows
1045 public function numRows( $res ) {
1046 if ( $res instanceof ResultWrapper
) {
1047 $res = $res->result
;
1050 if ( $this->mNumRows
) {
1051 return $this->mNumRows
;
1058 * Moves the row pointer of the result set
1059 * @param $res Object: result set
1060 * @param $row Integer: row number
1061 * @return success or failure
1063 public function dataSeek( $res, $row ) {
1064 if ( $res instanceof ResultWrapper
) {
1065 $res = $res->result
;
1067 return db2_fetch_row( $res, $row );
1071 # Fix notices in Block.php
1075 * Frees memory associated with a statement resource
1076 * @param $res Object: statement resource to free
1077 * @return Boolean success or failure
1079 public function freeResult( $res ) {
1080 if ( $res instanceof ResultWrapper
) {
1081 $res = $res->result
;
1083 wfSuppressWarnings();
1084 $ok = db2_free_result( $res );
1085 wfRestoreWarnings();
1087 throw new DBUnexpectedError( $this, "Unable to free DB2 result\n" );
1092 * Returns the number of columns in a resource
1093 * @param $res Object: statement resource
1094 * @return Number of fields/columns in resource
1096 public function numFields( $res ) {
1097 if ( $res instanceof ResultWrapper
) {
1098 $res = $res->result
;
1100 return db2_num_fields( $res );
1104 * Returns the nth column name
1105 * @param $res Object: statement resource
1106 * @param $n Integer: Index of field or column
1107 * @return String name of nth column
1109 public function fieldName( $res, $n ) {
1110 if ( $res instanceof ResultWrapper
) {
1111 $res = $res->result
;
1113 return db2_field_name( $res, $n );
1119 * @param $table Array or string, table name(s) (prefix auto-added)
1120 * @param $vars Array or string, field name(s) to be retrieved
1121 * @param $conds Array or string, condition(s) for WHERE
1122 * @param $fname String: calling function name (use __METHOD__)
1123 * for logs/profiling
1124 * @param $options Associative array of options
1125 * (e.g. array('GROUP BY' => 'page_title')),
1126 * see Database::makeSelectOptions code for list of
1128 * @param $join_conds Associative array of table join conditions (optional)
1129 * (e.g. array( 'page' => array('LEFT JOIN',
1130 * 'page_latest=rev_id') )
1131 * @return Mixed: database result resource for fetch functions or false
1134 public function select( $table, $vars, $conds = '', $fname = 'DatabaseIbm_db2::select', $options = array(), $join_conds = array() )
1136 $res = parent
::select( $table, $vars, $conds, $fname, $options,
1139 // We must adjust for offset
1140 if ( isset( $options['LIMIT'] ) && isset ( $options['OFFSET'] ) ) {
1141 $limit = $options['LIMIT'];
1142 $offset = $options['OFFSET'];
1145 // DB2 does not have a proper num_rows() function yet, so we must emulate
1146 // DB2 9.5.4 and the corresponding ibm_db2 driver will introduce
1150 // we want the count
1151 $vars2 = array( 'count( * ) as num_rows' );
1152 // respecting just the limit option
1153 $options2 = array();
1154 if ( isset( $options['LIMIT'] ) ) {
1155 $options2['LIMIT'] = $options['LIMIT'];
1157 // but don't try to emulate for GROUP BY
1158 if ( isset( $options['GROUP BY'] ) ) {
1162 $res2 = parent
::select( $table, $vars2, $conds, $fname, $options2,
1164 $obj = $this->fetchObject( $res2 );
1165 $this->mNumRows
= $obj->num_rows
;
1171 * Handles ordering, grouping, and having options ('GROUP BY' => colname)
1172 * Has limited support for per-column options (colnum => 'DISTINCT')
1176 * @param $options Associative array of options to be turned into
1177 * an SQL query, valid keys are listed in the function.
1180 function makeSelectOptions( $options ) {
1181 $preLimitTail = $postLimitTail = '';
1184 $noKeyOptions = array();
1185 foreach ( $options as $key => $option ) {
1186 if ( is_numeric( $key ) ) {
1187 $noKeyOptions[$option] = true;
1191 if ( isset( $options['GROUP BY'] ) ) {
1192 $preLimitTail .= " GROUP BY {$options['GROUP BY']}";
1194 if ( isset( $options['HAVING'] ) ) {
1195 $preLimitTail .= " HAVING {$options['HAVING']}";
1197 if ( isset( $options['ORDER BY'] ) ) {
1198 $preLimitTail .= " ORDER BY {$options['ORDER BY']}";
1201 if ( isset( $noKeyOptions['DISTINCT'] )
1202 ||
isset( $noKeyOptions['DISTINCTROW'] ) )
1204 $startOpts .= 'DISTINCT';
1207 return array( $startOpts, '', $preLimitTail, $postLimitTail );
1211 * Returns link to IBM DB2 free download
1212 * @return String: wikitext of a link to the server software's web site
1214 public static function getSoftwareLink() {
1215 return '[http://www.ibm.com/db2/express/ IBM DB2]';
1219 * Get search engine class. All subclasses of this
1220 * need to implement this if they wish to use searching.
1224 public function getSearchEngine() {
1225 return 'SearchIBM_DB2';
1229 * Did the last database access fail because of deadlock?
1232 public function wasDeadlock() {
1234 $err = $this->lastErrno();
1236 // This is literal port of the MySQL logic and may be wrong for DB2
1237 case '40001': // sql0911n, Deadlock or timeout, rollback
1238 case '57011': // sql0904n, Resource unavailable, no rollback
1239 case '57033': // sql0913n, Deadlock or timeout, no rollback
1240 $this->installPrint( "In a deadlock because of SQLSTATE $err" );
1247 * Ping the server and try to reconnect if it there is no connection
1248 * The connection may be closed and reopened while this happens
1249 * @return Boolean: whether the connection exists
1251 public function ping() {
1252 // db2_ping() doesn't exist
1255 $this->mConn
= $this->openUncataloged( $this->mDBName
, $this->mUser
,
1256 $this->mPassword
, $this->mServer
, $this->mPort
);
1260 ######################################
1261 # Unimplemented and not applicable
1262 ######################################
1265 * @return string $sql
1267 public function limitResultForUpdate( $sql, $num ) {
1268 $this->installPrint( 'Not implemented for DB2: limitResultForUpdate()' );
1273 * Only useful with fake prepare like in base Database class
1276 public function fillPreparedArg( $matches ) {
1277 $this->installPrint( 'Not useful for DB2: fillPreparedArg()' );
1281 ######################################
1283 ######################################
1286 * Returns information about an index
1287 * If errors are explicitly ignored, returns NULL on failure
1288 * @param $table String: table name
1289 * @param $index String: index name
1290 * @param $fname String: function name for logging and profiling
1291 * @return Object query row in object form
1293 public function indexInfo( $table, $index,
1294 $fname = 'DatabaseIbm_db2::indexExists' )
1296 $table = $this->tableName( $table );
1298 SELECT name as indexname
1299 FROM sysibm.sysindexes si
1300 WHERE si.name='$index' AND si.tbname='$table'
1301 AND sc.tbcreator='$this->mSchema'
1303 $res = $this->query( $sql, $fname );
1307 $row = $this->fetchObject( $res );
1308 if ( $row != null ) {
1316 * Returns an information object on a table column
1317 * @param $table String: table name
1318 * @param $field String: column name
1319 * @return IBM_DB2Field
1321 public function fieldInfo( $table, $field ) {
1322 return IBM_DB2Field
::fromText( $this, $table, $field );
1326 * db2_field_type() wrapper
1327 * @param $res Object: result of executed statement
1328 * @param $index Mixed: number or name of the column
1329 * @return String column type
1331 public function fieldType( $res, $index ) {
1332 if ( $res instanceof ResultWrapper
) {
1333 $res = $res->result
;
1335 return db2_field_type( $res, $index );
1339 * Verifies that an index was created as unique
1340 * @param $table String: table name
1341 * @param $index String: index name
1342 * @param $fname function name for profiling
1345 public function indexUnique ( $table, $index,
1346 $fname = 'DatabaseIbm_db2::indexUnique' )
1348 $table = $this->tableName( $table );
1350 SELECT si.name as indexname
1351 FROM sysibm.sysindexes si
1352 WHERE si.name='$index' AND si.tbname='$table'
1353 AND sc.tbcreator='$this->mSchema'
1354 AND si.uniquerule IN ( 'U', 'P' )
1356 $res = $this->query( $sql, $fname );
1360 if ( $this->fetchObject( $res ) ) {
1368 * Returns the size of a text field, or -1 for "unlimited"
1369 * @param $table String: table name
1370 * @param $field String: column name
1371 * @return Integer: length or -1 for unlimited
1373 public function textFieldSize( $table, $field ) {
1374 $table = $this->tableName( $table );
1376 SELECT length as size
1377 FROM sysibm.syscolumns sc
1378 WHERE sc.name='$field' AND sc.tbname='$table'
1379 AND sc.tbcreator='$this->mSchema'
1381 $res = $this->query( $sql );
1382 $row = $this->fetchObject( $res );
1388 * Description is left as an exercise for the reader
1389 * @param $b Mixed: data to be encoded
1390 * @return IBM_DB2Blob
1392 public function encodeBlob( $b ) {
1393 return new IBM_DB2Blob( $b );
1397 * Description is left as an exercise for the reader
1398 * @param $b IBM_DB2Blob: data to be decoded
1401 public function decodeBlob( $b ) {
1406 * Convert into a list of string being concatenated
1407 * @param $stringList Array: strings that need to be joined together
1409 * @return String: joined by the concatenation operator
1411 public function buildConcat( $stringList ) {
1412 // || is equivalent to CONCAT
1413 // Sample query: VALUES 'foo' CONCAT 'bar' CONCAT 'baz'
1414 return implode( ' || ', $stringList );
1418 * Generates the SQL required to convert a DB2 timestamp into a Unix epoch
1419 * @param $column String: name of timestamp column
1420 * @return String: SQL code
1422 public function extractUnixEpoch( $column ) {
1424 // see SpecialAncientpages
1427 ######################################
1428 # Prepared statements
1429 ######################################
1432 * Intended to be compatible with the PEAR::DB wrapper functions.
1433 * http://pear.php.net/manual/en/package.database.db.intro-execute.php
1435 * ? = scalar value, quoted as necessary
1436 * ! = raw SQL bit (a function for instance)
1437 * & = filename; reads the file and inserts as a blob
1438 * (we don't use this though...)
1439 * @param $sql String: SQL statement with appropriate markers
1440 * @param $func String: Name of the function, for profiling
1441 * @return resource a prepared DB2 SQL statement
1443 public function prepare( $sql, $func = 'DB2::prepare' ) {
1444 $stmt = db2_prepare( $this->mConn
, $sql, $this->mStmtOptions
);
1449 * Frees resources associated with a prepared statement
1450 * @return Boolean success or failure
1452 public function freePrepared( $prepared ) {
1453 return db2_free_stmt( $prepared );
1457 * Execute a prepared query with the various arguments
1458 * @param $prepared String: the prepared sql
1459 * @param $args Mixed: either an array here, or put scalars as varargs
1460 * @return Resource: results object
1462 public function execute( $prepared, $args = null ) {
1463 if( !is_array( $args ) ) {
1465 $args = func_get_args();
1466 array_shift( $args );
1468 $res = db2_execute( $prepared, $args );
1470 $this->installPrint( db2_stmt_errormsg() );
1476 * Prepare & execute an SQL statement, quoting and inserting arguments
1477 * in the appropriate places.
1478 * @param $query String
1481 public function safeQuery( $query, $args = null ) {
1482 // copied verbatim from Database.php
1483 $prepared = $this->prepare( $query, 'DB2::safeQuery' );
1484 if( !is_array( $args ) ) {
1486 $args = func_get_args();
1487 array_shift( $args );
1489 $retval = $this->execute( $prepared, $args );
1490 $this->freePrepared( $prepared );
1495 * For faking prepared SQL statements on DBs that don't support
1497 * @param $preparedQuery String: a 'preparable' SQL statement
1498 * @param $args Array of arguments to fill it with
1499 * @return String: executable statement
1501 public function fillPrepared( $preparedQuery, $args ) {
1503 $this->preparedArgs
=& $args;
1505 foreach ( $args as $i => $arg ) {
1506 db2_bind_param( $preparedQuery, $i+
1, $args[$i] );
1509 return $preparedQuery;
1513 * Switches module between regular and install modes
1515 public function setMode( $mode ) {
1516 $old = $this->mMode
;
1517 $this->mMode
= $mode;
1522 * Bitwise negation of a column or value in SQL
1523 * Same as (~field) in C
1524 * @param $field String
1527 function bitNot( $field ) {
1528 // expecting bit-fields smaller than 4bytes
1529 return "BITNOT( $field )";
1533 * Bitwise AND of two columns or values in SQL
1534 * Same as (fieldLeft & fieldRight) in C
1535 * @param $fieldLeft String
1536 * @param $fieldRight String
1539 function bitAnd( $fieldLeft, $fieldRight ) {
1540 return "BITAND( $fieldLeft, $fieldRight )";
1544 * Bitwise OR of two columns or values in SQL
1545 * Same as (fieldLeft | fieldRight) in C
1546 * @param $fieldLeft String
1547 * @param $fieldRight String
1550 function bitOr( $fieldLeft, $fieldRight ) {
1551 return "BITOR( $fieldLeft, $fieldRight )";
1555 class IBM_DB2Helper
{
1556 public static function makeArray( $maybeArray ) {
1557 if ( !is_array( $maybeArray ) ) {
1558 return array( $maybeArray );