3 * @defgroup Database Database
5 * This file deals with database interface functions
6 * and query specifics/optimisations.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21 * http://www.gnu.org/copyleft/gpl.html
26 namespace Wikimedia\Rdbms
;
28 use Psr\Log\LoggerAwareInterface
;
29 use Psr\Log\LoggerInterface
;
30 use Psr\Log\NullLogger
;
31 use Wikimedia\ScopedCallback
;
32 use Wikimedia\Timestamp\ConvertibleTimestamp
;
37 use InvalidArgumentException
;
38 use UnexpectedValueException
;
43 * Relational database abstraction object
48 abstract class Database
implements IDatabase
, IMaintainableDatabase
, LoggerAwareInterface
{
49 /** Number of times to re-try an operation in case of deadlock */
50 const DEADLOCK_TRIES
= 4;
51 /** Minimum time to wait before retry, in microseconds */
52 const DEADLOCK_DELAY_MIN
= 500000;
53 /** Maximum time to wait before retry */
54 const DEADLOCK_DELAY_MAX
= 1500000;
56 /** How long before it is worth doing a dummy query to test the connection */
58 const PING_QUERY
= 'SELECT 1 AS ping';
60 const TINY_WRITE_SEC
= 0.010;
61 const SLOW_WRITE_SEC
= 0.500;
62 const SMALL_WRITE_ROWS
= 100;
64 /** @var string Whether lock granularity is on the level of the entire database */
65 const ATTR_DB_LEVEL_LOCKING
= 'db-level-locking';
67 /** @var int New Database instance will not be connected yet when returned */
68 const NEW_UNCONNECTED
= 0;
69 /** @var int New Database instance will already be connected when returned */
70 const NEW_CONNECTED
= 1;
72 /** @var string SQL query */
73 protected $lastQuery = '';
74 /** @var float|bool UNIX timestamp of last write query */
75 protected $lastWriteTime = false;
76 /** @var string|bool */
77 protected $phpError = false;
78 /** @var string Server that this instance is currently connected to */
80 /** @var string User that this instance is currently connected under the name of */
82 /** @var string Password used to establish the current connection */
84 /** @var string Database that this instance is currently connected to */
86 /** @var array[] Map of (table => (dbname, schema, prefix) map) */
87 protected $tableAliases = [];
88 /** @var string[] Map of (index alias => index) */
89 protected $indexAliases = [];
90 /** @var bool Whether this PHP instance is for a CLI script */
92 /** @var string Agent name for query profiling */
94 /** @var array Parameters used by initConnection() to establish a connection */
95 protected $connectionParams = [];
96 /** @var BagOStuff APC cache */
98 /** @var LoggerInterface */
99 protected $connLogger;
100 /** @var LoggerInterface */
101 protected $queryLogger;
102 /** @var callback Error logging callback */
103 protected $errorLogger;
104 /** @var callback Deprecation logging callback */
105 protected $deprecationLogger;
107 /** @var resource|null Database connection */
108 protected $conn = null;
110 protected $opened = false;
112 /** @var array[] List of (callable, method name, atomic section id) */
113 protected $trxIdleCallbacks = [];
114 /** @var array[] List of (callable, method name, atomic section id) */
115 protected $trxPreCommitCallbacks = [];
116 /** @var array[] List of (callable, method name, atomic section id) */
117 protected $trxEndCallbacks = [];
118 /** @var callable[] Map of (name => callable) */
119 protected $trxRecurringCallbacks = [];
120 /** @var bool Whether to suppress triggering of transaction end callbacks */
121 protected $trxEndCallbacksSuppressed = false;
124 protected $tablePrefix = '';
126 protected $schema = '';
130 protected $lbInfo = [];
131 /** @var array|bool */
132 protected $schemaVars = false;
134 protected $sessionVars = [];
135 /** @var array|null */
136 protected $preparedArgs;
137 /** @var string|bool|null Stashed value of html_errors INI setting */
138 protected $htmlErrors;
140 protected $delimiter = ';';
141 /** @var DatabaseDomain */
142 protected $currentDomain;
143 /** @var integer|null Rows affected by the last query to query() or its CRUD wrappers */
144 protected $affectedRowCount;
147 * @var int Transaction status
149 protected $trxStatus = self
::STATUS_TRX_NONE
;
151 * @var Exception|null The last error that caused the status to become STATUS_TRX_ERROR
153 protected $trxStatusCause;
155 * @var array|null If wasKnownStatementRollbackError() prevented trxStatus from being set,
156 * the relevant details are stored here.
158 protected $trxStatusIgnoredCause;
160 * Either 1 if a transaction is active or 0 otherwise.
161 * The other Trx fields may not be meaningfull if this is 0.
165 protected $trxLevel = 0;
167 * Either a short hexidecimal string if a transaction is active or ""
170 * @see Database::trxLevel
172 protected $trxShortId = '';
174 * The UNIX time that the transaction started. Callers can assume that if
175 * snapshot isolation is used, then the data is *at least* up to date to that
176 * point (possibly more up-to-date since the first SELECT defines the snapshot).
179 * @see Database::trxLevel
181 private $trxTimestamp = null;
182 /** @var float Lag estimate at the time of BEGIN */
183 private $trxReplicaLag = null;
185 * Remembers the function name given for starting the most recent transaction via begin().
186 * Used to provide additional context for error reporting.
189 * @see Database::trxLevel
191 private $trxFname = null;
193 * Record if possible write queries were done in the last transaction started
196 * @see Database::trxLevel
198 private $trxDoneWrites = false;
200 * Record if the current transaction was started implicitly due to DBO_TRX being set.
203 * @see Database::trxLevel
205 private $trxAutomatic = false;
207 * Counter for atomic savepoint identifiers. Reset when a new transaction begins.
211 private $trxAtomicCounter = 0;
213 * Array of levels of atomicity within transactions
215 * @var array List of (name, unique ID, savepoint ID)
217 private $trxAtomicLevels = [];
219 * Record if the current transaction was started implicitly by Database::startAtomic
223 private $trxAutomaticAtomic = false;
225 * Track the write query callers of the current transaction
229 private $trxWriteCallers = [];
231 * @var float Seconds spent in write queries for the current transaction
233 private $trxWriteDuration = 0.0;
235 * @var int Number of write queries for the current transaction
237 private $trxWriteQueryCount = 0;
239 * @var int Number of rows affected by write queries for the current transaction
241 private $trxWriteAffectedRows = 0;
243 * @var float Like trxWriteQueryCount but excludes lock-bound, easy to replicate, queries
245 private $trxWriteAdjDuration = 0.0;
247 * @var int Number of write queries counted in trxWriteAdjDuration
249 private $trxWriteAdjQueryCount = 0;
251 * @var float RTT time estimate
253 private $rttEstimate = 0.0;
255 /** @var array Map of (name => 1) for locks obtained via lock() */
256 private $namedLocksHeld = [];
257 /** @var array Map of (table name => 1) for TEMPORARY tables */
258 protected $sessionTempTables = [];
260 /** @var IDatabase|null Lazy handle to the master DB this server replicates from */
261 private $lazyMasterHandle;
263 /** @var float UNIX timestamp */
264 protected $lastPing = 0.0;
266 /** @var int[] Prior flags member variable values */
267 private $priorFlags = [];
269 /** @var object|string Class name or object With profileIn/profileOut methods */
271 /** @var TransactionProfiler */
272 protected $trxProfiler;
275 protected $nonNativeInsertSelectBatchSize = 10000;
277 /** @var string Idiom used when a cancelable atomic section started the transaction */
278 private static $NOT_APPLICABLE = 'n/a';
279 /** @var string Prefix to the atomic section counter used to make savepoint IDs */
280 private static $SAVEPOINT_PREFIX = 'wikimedia_rdbms_atomic';
282 /** @var int Transaction is in a error state requiring a full or savepoint rollback */
283 const STATUS_TRX_ERROR
= 1;
284 /** @var int Transaction is active and in a normal state */
285 const STATUS_TRX_OK
= 2;
286 /** @var int No transaction is active */
287 const STATUS_TRX_NONE
= 3;
290 * @note: exceptions for missing libraries/drivers should be thrown in initConnection()
291 * @param array $params Parameters passed from Database::factory()
293 protected function __construct( array $params ) {
294 foreach ( [ 'host', 'user', 'password', 'dbname' ] as $name ) {
295 $this->connectionParams
[$name] = $params[$name];
298 $this->schema
= $params['schema'];
299 $this->tablePrefix
= $params['tablePrefix'];
301 $this->cliMode
= $params['cliMode'];
302 // Agent name is added to SQL queries in a comment, so make sure it can't break out
303 $this->agent
= str_replace( '/', '-', $params['agent'] );
305 $this->flags
= $params['flags'];
306 if ( $this->flags
& self
::DBO_DEFAULT
) {
307 if ( $this->cliMode
) {
308 $this->flags
&= ~self
::DBO_TRX
;
310 $this->flags |
= self
::DBO_TRX
;
313 // Disregard deprecated DBO_IGNORE flag (T189999)
314 $this->flags
&= ~self
::DBO_IGNORE
;
316 $this->sessionVars
= $params['variables'];
318 $this->srvCache
= $params['srvCache'] ??
new HashBagOStuff();
320 $this->profiler
= $params['profiler'];
321 $this->trxProfiler
= $params['trxProfiler'];
322 $this->connLogger
= $params['connLogger'];
323 $this->queryLogger
= $params['queryLogger'];
324 $this->errorLogger
= $params['errorLogger'];
325 $this->deprecationLogger
= $params['deprecationLogger'];
327 if ( isset( $params['nonNativeInsertSelectBatchSize'] ) ) {
328 $this->nonNativeInsertSelectBatchSize
= $params['nonNativeInsertSelectBatchSize'];
331 // Set initial dummy domain until open() sets the final DB/prefix
332 $this->currentDomain
= DatabaseDomain
::newUnspecified();
336 * Initialize the connection to the database over the wire (or to local files)
338 * @throws LogicException
339 * @throws InvalidArgumentException
340 * @throws DBConnectionError
343 final public function initConnection() {
344 if ( $this->isOpen() ) {
345 throw new LogicException( __METHOD__
. ': already connected.' );
347 // Establish the connection
348 $this->doInitConnection();
349 // Set the domain object after open() sets the relevant fields
350 if ( $this->dbName
!= '' ) {
351 // Domains with server scope but a table prefix are not used by IDatabase classes
352 $this->currentDomain
= new DatabaseDomain( $this->dbName
, null, $this->tablePrefix
);
357 * Actually connect to the database over the wire (or to local files)
359 * @throws InvalidArgumentException
360 * @throws DBConnectionError
363 protected function doInitConnection() {
364 if ( strlen( $this->connectionParams
['user'] ) ) {
366 $this->connectionParams
['host'],
367 $this->connectionParams
['user'],
368 $this->connectionParams
['password'],
369 $this->connectionParams
['dbname']
372 throw new InvalidArgumentException( "No database user provided." );
377 * Construct a Database subclass instance given a database type and parameters
379 * This also connects to the database immediately upon object construction
381 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
382 * @param array $p Parameter map with keys:
383 * - host : The hostname of the DB server
384 * - user : The name of the database user the client operates under
385 * - password : The password for the database user
386 * - dbname : The name of the database to use where queries do not specify one.
387 * The database must exist or an error might be thrown. Setting this to the empty string
388 * will avoid any such errors and make the handle have no implicit database scope. This is
389 * useful for queries like SHOW STATUS, CREATE DATABASE, or DROP DATABASE. Note that a
390 * "database" in Postgres is rougly equivalent to an entire MySQL server. This the domain
391 * in which user names and such are defined, e.g. users are database-specific in Postgres.
392 * - schema : The database schema to use (if supported). A "schema" in Postgres is roughly
393 * equivalent to a "database" in MySQL. Note that MySQL and SQLite do not use schemas.
394 * - tablePrefix : Optional table prefix that is implicitly added on to all table names
395 * recognized in queries. This can be used in place of schemas for handle site farms.
396 * - flags : Optional bitfield of DBO_* constants that define connection, protocol,
397 * buffering, and transaction behavior. It is STRONGLY adviced to leave the DBO_DEFAULT
398 * flag in place UNLESS this this database simply acts as a key/value store.
399 * - driver: Optional name of a specific DB client driver. For MySQL, there is only the
400 * 'mysqli' driver; the old one 'mysql' has been removed.
401 * - variables: Optional map of session variables to set after connecting. This can be
402 * used to adjust lock timeouts or encoding modes and the like.
403 * - connLogger: Optional PSR-3 logger interface instance.
404 * - queryLogger: Optional PSR-3 logger interface instance.
405 * - profiler: Optional class name or object with profileIn()/profileOut() methods.
406 * These will be called in query(), using a simplified version of the SQL that also
407 * includes the agent as a SQL comment.
408 * - trxProfiler: Optional TransactionProfiler instance.
409 * - errorLogger: Optional callback that takes an Exception and logs it.
410 * - deprecationLogger: Optional callback that takes a string and logs it.
411 * - cliMode: Whether to consider the execution context that of a CLI script.
412 * - agent: Optional name used to identify the end-user in query profiling/logging.
413 * - srvCache: Optional BagOStuff instance to an APC-style cache.
414 * - nonNativeInsertSelectBatchSize: Optional batch size for non-native INSERT SELECT emulation.
415 * @param int $connect One of the class constants (NEW_CONNECTED, NEW_UNCONNECTED) [optional]
416 * @return Database|null If the database driver or extension cannot be found
417 * @throws InvalidArgumentException If the database driver or extension cannot be found
420 final public static function factory( $dbType, $p = [], $connect = self
::NEW_CONNECTED
) {
421 $class = self
::getClass( $dbType, $p['driver'] ??
null );
423 if ( class_exists( $class ) && is_subclass_of( $class, IDatabase
::class ) ) {
424 // Resolve some defaults for b/c
425 $p['host'] = $p['host'] ??
false;
426 $p['user'] = $p['user'] ??
false;
427 $p['password'] = $p['password'] ??
false;
428 $p['dbname'] = $p['dbname'] ??
false;
429 $p['flags'] = $p['flags'] ??
0;
430 $p['variables'] = $p['variables'] ??
[];
431 $p['tablePrefix'] = $p['tablePrefix'] ??
'';
432 $p['schema'] = $p['schema'] ??
'';
433 $p['cliMode'] = $p['cliMode'] ??
( PHP_SAPI
=== 'cli' || PHP_SAPI
=== 'phpdbg' );
434 $p['agent'] = $p['agent'] ??
'';
435 if ( !isset( $p['connLogger'] ) ) {
436 $p['connLogger'] = new NullLogger();
438 if ( !isset( $p['queryLogger'] ) ) {
439 $p['queryLogger'] = new NullLogger();
441 $p['profiler'] = $p['profiler'] ??
null;
442 if ( !isset( $p['trxProfiler'] ) ) {
443 $p['trxProfiler'] = new TransactionProfiler();
445 if ( !isset( $p['errorLogger'] ) ) {
446 $p['errorLogger'] = function ( Exception
$e ) {
447 trigger_error( get_class( $e ) . ': ' . $e->getMessage(), E_USER_WARNING
);
450 if ( !isset( $p['deprecationLogger'] ) ) {
451 $p['deprecationLogger'] = function ( $msg ) {
452 trigger_error( $msg, E_USER_DEPRECATED
);
456 /** @var Database $conn */
457 $conn = new $class( $p );
458 if ( $connect == self
::NEW_CONNECTED
) {
459 $conn->initConnection();
469 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
470 * @param string|null $driver Optional name of a specific DB client driver
471 * @return array Map of (Database::ATTRIBUTE_* constant => value) for all such constants
472 * @throws InvalidArgumentException
475 final public static function attributesFromType( $dbType, $driver = null ) {
476 static $defaults = [ self
::ATTR_DB_LEVEL_LOCKING
=> false ];
478 $class = self
::getClass( $dbType, $driver );
480 return call_user_func( [ $class, 'getAttributes' ] ) +
$defaults;
484 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
485 * @param string|null $driver Optional name of a specific DB client driver
486 * @return string Database subclass name to use
487 * @throws InvalidArgumentException
489 private static function getClass( $dbType, $driver = null ) {
490 // For database types with built-in support, the below maps type to IDatabase
491 // implementations. For types with multipe driver implementations (PHP extensions),
492 // an array can be used, keyed by extension name. In case of an array, the
493 // optional 'driver' parameter can be used to force a specific driver. Otherwise,
494 // we auto-detect the first available driver. For types without built-in support,
495 // an class named "Database<Type>" us used, eg. DatabaseFoo for type 'foo'.
496 static $builtinTypes = [
497 'mssql' => DatabaseMssql
::class,
498 'mysql' => [ 'mysqli' => DatabaseMysqli
::class ],
499 'sqlite' => DatabaseSqlite
::class,
500 'postgres' => DatabasePostgres
::class,
503 $dbType = strtolower( $dbType );
506 if ( isset( $builtinTypes[$dbType] ) ) {
507 $possibleDrivers = $builtinTypes[$dbType];
508 if ( is_string( $possibleDrivers ) ) {
509 $class = $possibleDrivers;
511 if ( (string)$driver !== '' ) {
512 if ( !isset( $possibleDrivers[$driver] ) ) {
513 throw new InvalidArgumentException( __METHOD__
.
514 " type '$dbType' does not support driver '{$driver}'" );
516 $class = $possibleDrivers[$driver];
519 foreach ( $possibleDrivers as $posDriver => $possibleClass ) {
520 if ( extension_loaded( $posDriver ) ) {
521 $class = $possibleClass;
528 $class = 'Database' . ucfirst( $dbType );
531 if ( $class === false ) {
532 throw new InvalidArgumentException( __METHOD__
.
533 " no viable database extension found for type '$dbType'" );
540 * @return array Map of (Database::ATTRIBUTE_* constant => value
543 protected static function getAttributes() {
548 * Set the PSR-3 logger interface to use for query logging. (The logger
549 * interfaces for connection logging and error logging can be set with the
552 * @param LoggerInterface $logger
554 public function setLogger( LoggerInterface
$logger ) {
555 $this->queryLogger
= $logger;
558 public function getServerInfo() {
559 return $this->getServerVersion();
562 public function bufferResults( $buffer = null ) {
563 $res = !$this->getFlag( self
::DBO_NOBUFFER
);
564 if ( $buffer !== null ) {
566 ?
$this->clearFlag( self
::DBO_NOBUFFER
)
567 : $this->setFlag( self
::DBO_NOBUFFER
);
573 public function trxLevel() {
574 return $this->trxLevel
;
577 public function trxTimestamp() {
578 return $this->trxLevel ?
$this->trxTimestamp
: null;
582 * @return int One of the STATUS_TRX_* class constants
585 public function trxStatus() {
586 return $this->trxStatus
;
589 public function tablePrefix( $prefix = null ) {
590 $old = $this->tablePrefix
;
591 if ( $prefix !== null ) {
592 $this->tablePrefix
= $prefix;
593 $this->currentDomain
= ( $this->dbName
!= '' )
594 ?
new DatabaseDomain( $this->dbName
, null, $this->tablePrefix
)
595 : DatabaseDomain
::newUnspecified();
601 public function dbSchema( $schema = null ) {
602 $old = $this->schema
;
603 if ( $schema !== null ) {
604 $this->schema
= $schema;
610 public function getLBInfo( $name = null ) {
611 if ( is_null( $name ) ) {
612 return $this->lbInfo
;
614 if ( array_key_exists( $name, $this->lbInfo
) ) {
615 return $this->lbInfo
[$name];
622 public function setLBInfo( $name, $value = null ) {
623 if ( is_null( $value ) ) {
624 $this->lbInfo
= $name;
626 $this->lbInfo
[$name] = $value;
630 public function setLazyMasterHandle( IDatabase
$conn ) {
631 $this->lazyMasterHandle
= $conn;
635 * @return IDatabase|null
636 * @see setLazyMasterHandle()
639 protected function getLazyMasterHandle() {
640 return $this->lazyMasterHandle
;
643 public function implicitGroupby() {
647 public function implicitOrderby() {
651 public function lastQuery() {
652 return $this->lastQuery
;
655 public function doneWrites() {
656 return (bool)$this->lastWriteTime
;
659 public function lastDoneWrites() {
660 return $this->lastWriteTime ?
: false;
663 public function writesPending() {
664 return $this->trxLevel
&& $this->trxDoneWrites
;
667 public function writesOrCallbacksPending() {
668 return $this->trxLevel
&& (
669 $this->trxDoneWrites ||
670 $this->trxIdleCallbacks ||
671 $this->trxPreCommitCallbacks ||
672 $this->trxEndCallbacks
676 public function preCommitCallbacksPending() {
677 return $this->trxLevel
&& $this->trxPreCommitCallbacks
;
681 * @return string|null
683 final protected function getTransactionRoundId() {
684 // If transaction round participation is enabled, see if one is active
685 if ( $this->getFlag( self
::DBO_TRX
) ) {
686 $id = $this->getLBInfo( 'trxRoundId' );
688 return is_string( $id ) ?
$id : null;
694 public function pendingWriteQueryDuration( $type = self
::ESTIMATE_TOTAL
) {
695 if ( !$this->trxLevel
) {
697 } elseif ( !$this->trxDoneWrites
) {
702 case self
::ESTIMATE_DB_APPLY
:
704 $rttAdjTotal = $this->trxWriteAdjQueryCount
* $rtt;
705 $applyTime = max( $this->trxWriteAdjDuration
- $rttAdjTotal, 0 );
706 // For omitted queries, make them count as something at least
707 $omitted = $this->trxWriteQueryCount
- $this->trxWriteAdjQueryCount
;
708 $applyTime +
= self
::TINY_WRITE_SEC
* $omitted;
711 default: // everything
712 return $this->trxWriteDuration
;
716 public function pendingWriteCallers() {
717 return $this->trxLevel ?
$this->trxWriteCallers
: [];
720 public function pendingWriteRowsAffected() {
721 return $this->trxWriteAffectedRows
;
725 * List the methods that have write queries or callbacks for the current transaction
727 * This method should not be used outside of Database/LoadBalancer
732 public function pendingWriteAndCallbackCallers() {
733 $fnames = $this->pendingWriteCallers();
735 $this->trxIdleCallbacks
,
736 $this->trxPreCommitCallbacks
,
737 $this->trxEndCallbacks
739 foreach ( $callbacks as $callback ) {
740 $fnames[] = $callback[1];
750 private function flatAtomicSectionList() {
751 return array_reduce( $this->trxAtomicLevels
, function ( $accum, $v ) {
752 return $accum === null ?
$v[0] : "$accum, " . $v[0];
756 public function isOpen() {
757 return $this->opened
;
760 public function setFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
761 if ( ( $flag & self
::DBO_IGNORE
) ) {
762 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
765 if ( $remember === self
::REMEMBER_PRIOR
) {
766 array_push( $this->priorFlags
, $this->flags
);
768 $this->flags |
= $flag;
771 public function clearFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
772 if ( ( $flag & self
::DBO_IGNORE
) ) {
773 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
776 if ( $remember === self
::REMEMBER_PRIOR
) {
777 array_push( $this->priorFlags
, $this->flags
);
779 $this->flags
&= ~
$flag;
782 public function restoreFlags( $state = self
::RESTORE_PRIOR
) {
783 if ( !$this->priorFlags
) {
787 if ( $state === self
::RESTORE_INITIAL
) {
788 $this->flags
= reset( $this->priorFlags
);
789 $this->priorFlags
= [];
791 $this->flags
= array_pop( $this->priorFlags
);
795 public function getFlag( $flag ) {
796 return !!( $this->flags
& $flag );
800 * @param string $name Class field name
802 * @deprecated Since 1.28
804 public function getProperty( $name ) {
808 public function getDomainID() {
809 return $this->currentDomain
->getId();
812 final public function getWikiID() {
813 return $this->getDomainID();
817 * Get information about an index into an object
818 * @param string $table Table name
819 * @param string $index Index name
820 * @param string $fname Calling function name
821 * @return mixed Database-specific index description class or false if the index does not exist
823 abstract function indexInfo( $table, $index, $fname = __METHOD__
);
826 * Wrapper for addslashes()
828 * @param string $s String to be slashed.
829 * @return string Slashed string.
831 abstract function strencode( $s );
834 * Set a custom error handler for logging errors during database connection
836 protected function installErrorHandler() {
837 $this->phpError
= false;
838 $this->htmlErrors
= ini_set( 'html_errors', '0' );
839 set_error_handler( [ $this, 'connectionErrorLogger' ] );
843 * Restore the previous error handler and return the last PHP error for this DB
845 * @return bool|string
847 protected function restoreErrorHandler() {
848 restore_error_handler();
849 if ( $this->htmlErrors
!== false ) {
850 ini_set( 'html_errors', $this->htmlErrors
);
853 return $this->getLastPHPError();
857 * @return string|bool Last PHP error for this DB (typically connection errors)
859 protected function getLastPHPError() {
860 if ( $this->phpError
) {
861 $error = preg_replace( '!\[<a.*</a>\]!', '', $this->phpError
);
862 $error = preg_replace( '!^.*?:\s?(.*)$!', '$1', $error );
871 * Error handler for logging errors during database connection
872 * This method should not be used outside of Database classes
875 * @param string $errstr
877 public function connectionErrorLogger( $errno, $errstr ) {
878 $this->phpError
= $errstr;
882 * Create a log context to pass to PSR-3 logger functions.
884 * @param array $extras Additional data to add to context
887 protected function getLogContext( array $extras = [] ) {
890 'db_server' => $this->server
,
891 'db_name' => $this->dbName
,
892 'db_user' => $this->user
,
898 final public function close() {
899 $exception = null; // error to throw after disconnecting
902 // Resolve any dangling transaction first
903 if ( $this->trxLevel
) {
904 if ( $this->trxAtomicLevels
) {
905 // Cannot let incomplete atomic sections be committed
906 $levels = $this->flatAtomicSectionList();
907 $exception = new DBUnexpectedError(
909 __METHOD__
. ": atomic sections $levels are still open."
911 } elseif ( $this->trxAutomatic
) {
912 // Only the connection manager can commit non-empty DBO_TRX transactions
913 if ( $this->writesOrCallbacksPending() ) {
914 $exception = new DBUnexpectedError(
917 ": mass commit/rollback of peer transaction required (DBO_TRX set)."
920 } elseif ( $this->trxLevel
) {
921 // Commit explicit transactions as if this was commit()
922 $this->queryLogger
->warning(
923 __METHOD__
. ": writes or callbacks still pending.",
924 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
928 if ( $this->trxEndCallbacksSuppressed
) {
929 $exception = $exception ?
: new DBUnexpectedError(
931 __METHOD__
. ': callbacks are suppressed; cannot properly commit.'
935 // Commit or rollback the changes and run any callbacks as needed
936 if ( $this->trxStatus
=== self
::STATUS_TRX_OK
&& !$exception ) {
939 $this->trxAutomatic ? self
::FLUSHING_INTERNAL
: self
::FLUSHING_ONE
942 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
946 // Close the actual connection in the binding handle
947 $closed = $this->closeConnection();
950 $closed = true; // already closed; nothing to do
953 $this->opened
= false;
955 // Throw any unexpected errors after having disconnected
956 if ( $exception instanceof Exception
) {
960 // Sanity check that no callbacks are dangling
961 $fnames = $this->pendingWriteAndCallbackCallers();
963 throw new RuntimeException(
964 "Transaction callbacks are still pending:\n" . implode( ', ', $fnames )
972 * Make sure isOpen() returns true as a sanity check
974 * @throws DBUnexpectedError
976 protected function assertOpen() {
977 if ( !$this->isOpen() ) {
978 throw new DBUnexpectedError( $this, "DB connection was already closed." );
983 * Closes underlying database connection
985 * @return bool Whether connection was closed successfully
987 abstract protected function closeConnection();
990 * @deprecated since 1.32
991 * @param string $error Fallback message, if none is given by DB
992 * @throws DBConnectionError
994 public function reportConnectionError( $error = 'Unknown error' ) {
995 call_user_func( $this->deprecationLogger
, 'Use of ' . __METHOD__
. ' is deprecated.' );
996 throw new DBConnectionError( $this, $this->lastError() ?
: $error );
1000 * Run a query and return a DBMS-dependent wrapper (that has all IResultWrapper methods)
1002 * This might return things, such as mysqli_result, that do not formally implement
1003 * IResultWrapper, but nonetheless implement all of its methods correctly
1005 * @param string $sql SQL query.
1006 * @return IResultWrapper|bool Iterator to feed to fetchObject/fetchRow; false on failure
1008 abstract protected function doQuery( $sql );
1011 * Determine whether a query writes to the DB.
1012 * Should return true if unsure.
1014 * @param string $sql
1017 protected function isWriteQuery( $sql ) {
1019 '/^(?:SELECT|BEGIN|ROLLBACK|COMMIT|SET|SHOW|EXPLAIN|\(SELECT)\b/i', $sql );
1023 * @param string $sql
1024 * @return string|null
1026 protected function getQueryVerb( $sql ) {
1027 return preg_match( '/^\s*([a-z]+)/i', $sql, $m ) ?
strtoupper( $m[1] ) : null;
1031 * Determine whether a SQL statement is sensitive to isolation level.
1032 * A SQL statement is considered transactable if its result could vary
1033 * depending on the transaction isolation level. Operational commands
1034 * such as 'SET' and 'SHOW' are not considered to be transactable.
1036 * @param string $sql
1039 protected function isTransactableQuery( $sql ) {
1041 $this->getQueryVerb( $sql ),
1042 [ 'BEGIN', 'COMMIT', 'ROLLBACK', 'SHOW', 'SET', 'CREATE', 'ALTER' ],
1048 * @param string $sql A SQL query
1049 * @return bool Whether $sql is SQL for TEMPORARY table operation
1051 protected function registerTempTableOperation( $sql ) {
1053 '/^CREATE\s+TEMPORARY\s+TABLE\s+(?:IF\s+NOT\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1057 $this->sessionTempTables
[$matches[1]] = 1;
1060 } elseif ( preg_match(
1061 '/^DROP\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1065 $isTemp = isset( $this->sessionTempTables
[$matches[1]] );
1066 unset( $this->sessionTempTables
[$matches[1]] );
1069 } elseif ( preg_match(
1070 '/^TRUNCATE\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1074 return isset( $this->sessionTempTables
[$matches[1]] );
1075 } elseif ( preg_match(
1076 '/^(?:INSERT\s+(?:\w+\s+)?INTO|UPDATE|DELETE\s+FROM)\s+[`"\']?(\w+)[`"\']?/i',
1080 return isset( $this->sessionTempTables
[$matches[1]] );
1086 public function query( $sql, $fname = __METHOD__
, $tempIgnore = false ) {
1087 $this->assertTransactionStatus( $sql, $fname );
1089 # Avoid fatals if close() was called
1090 $this->assertOpen();
1092 $priorWritesPending = $this->writesOrCallbacksPending();
1093 $this->lastQuery
= $sql;
1095 $isWrite = $this->isWriteQuery( $sql );
1097 $isNonTempWrite = !$this->registerTempTableOperation( $sql );
1099 $isNonTempWrite = false;
1103 if ( $this->getLBInfo( 'replica' ) === true ) {
1106 'Write operations are not allowed on replica database connections.'
1109 # In theory, non-persistent writes are allowed in read-only mode, but due to things
1110 # like https://bugs.mysql.com/bug.php?id=33669 that might not work anyway...
1111 $reason = $this->getReadOnlyReason();
1112 if ( $reason !== false ) {
1113 throw new DBReadOnlyError( $this, "Database is read-only: $reason" );
1115 # Set a flag indicating that writes have been done
1116 $this->lastWriteTime
= microtime( true );
1119 # Add trace comment to the begin of the sql string, right after the operator.
1120 # Or, for one-word queries (like "BEGIN" or COMMIT") add it to the end (T44598)
1121 $commentedSql = preg_replace( '/\s|$/', " /* $fname {$this->agent} */ ", $sql, 1 );
1123 # Start implicit transactions that wrap the request if DBO_TRX is enabled
1124 if ( !$this->trxLevel
&& $this->getFlag( self
::DBO_TRX
)
1125 && $this->isTransactableQuery( $sql )
1127 $this->begin( __METHOD__
. " ($fname)", self
::TRANSACTION_INTERNAL
);
1128 $this->trxAutomatic
= true;
1131 # Keep track of whether the transaction has write queries pending
1132 if ( $this->trxLevel
&& !$this->trxDoneWrites
&& $isWrite ) {
1133 $this->trxDoneWrites
= true;
1134 $this->trxProfiler
->transactionWritingIn(
1135 $this->server
, $this->dbName
, $this->trxShortId
);
1138 if ( $this->getFlag( self
::DBO_DEBUG
) ) {
1139 $this->queryLogger
->debug( "{$this->dbName} {$commentedSql}" );
1142 # Send the query to the server and fetch any corresponding errors
1143 $ret = $this->doProfiledQuery( $sql, $commentedSql, $isNonTempWrite, $fname );
1144 $lastError = $this->lastError();
1145 $lastErrno = $this->lastErrno();
1147 # Try reconnecting if the connection was lost
1148 if ( $ret === false && $this->wasConnectionLoss() ) {
1149 # Check if any meaningful session state was lost
1150 $recoverable = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
1151 # Update session state tracking and try to restore the connection
1152 $reconnected = $this->replaceLostConnection( __METHOD__
);
1153 # Silently resend the query to the server if it is safe and possible
1154 if ( $reconnected && $recoverable ) {
1155 $ret = $this->doProfiledQuery( $sql, $commentedSql, $isNonTempWrite, $fname );
1156 $lastError = $this->lastError();
1157 $lastErrno = $this->lastErrno();
1159 if ( $ret === false && $this->wasConnectionLoss() ) {
1160 # Query probably causes disconnects; reconnect and do not re-run it
1161 $this->replaceLostConnection( __METHOD__
);
1166 if ( $ret === false ) {
1167 if ( $this->trxLevel
) {
1168 if ( $this->wasKnownStatementRollbackError() ) {
1169 # We're ignoring an error that caused just the current query to be aborted.
1170 # But log the cause so we can log a deprecation notice if a caller actually
1172 $this->trxStatusIgnoredCause
= [ $lastError, $lastErrno, $fname ];
1174 # Either the query was aborted or all queries after BEGIN where aborted.
1175 # In the first case, the only options going forward are (a) ROLLBACK, or
1176 # (b) ROLLBACK TO SAVEPOINT (if one was set). If the later case, the only
1177 # option is ROLLBACK, since the snapshots would have been released.
1178 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
1179 $this->trxStatusCause
=
1180 $this->makeQueryException( $lastError, $lastErrno, $sql, $fname );
1181 $tempIgnore = false; // cannot recover
1182 $this->trxStatusIgnoredCause
= null;
1186 $this->reportQueryError( $lastError, $lastErrno, $sql, $fname, $tempIgnore );
1189 return $this->resultObject( $ret );
1193 * Wrapper for query() that also handles profiling, logging, and affected row count updates
1195 * @param string $sql Original SQL query
1196 * @param string $commentedSql SQL query with debugging/trace comment
1197 * @param bool $isWrite Whether the query is a (non-temporary) write operation
1198 * @param string $fname Name of the calling function
1199 * @return bool|ResultWrapper True for a successful write query, ResultWrapper
1200 * object for a successful read query, or false on failure
1202 private function doProfiledQuery( $sql, $commentedSql, $isWrite, $fname ) {
1203 $isMaster = !is_null( $this->getLBInfo( 'master' ) );
1204 # generalizeSQL() will probably cut down the query to reasonable
1205 # logging size most of the time. The substr is really just a sanity check.
1207 $queryProf = 'query-m: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1209 $queryProf = 'query: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1212 # Include query transaction state
1213 $queryProf .= $this->trxShortId ?
" [TRX#{$this->trxShortId}]" : "";
1215 $startTime = microtime( true );
1216 if ( $this->profiler
) {
1217 $this->profiler
->profileIn( $queryProf );
1219 $this->affectedRowCount
= null;
1220 $ret = $this->doQuery( $commentedSql );
1221 $this->affectedRowCount
= $this->affectedRows();
1222 if ( $this->profiler
) {
1223 $this->profiler
->profileOut( $queryProf );
1225 $queryRuntime = max( microtime( true ) - $startTime, 0.0 );
1227 unset( $queryProfSection ); // profile out (if set)
1229 if ( $ret !== false ) {
1230 $this->lastPing
= $startTime;
1231 if ( $isWrite && $this->trxLevel
) {
1232 $this->updateTrxWriteQueryTime( $sql, $queryRuntime, $this->affectedRows() );
1233 $this->trxWriteCallers
[] = $fname;
1237 if ( $sql === self
::PING_QUERY
) {
1238 $this->rttEstimate
= $queryRuntime;
1241 $this->trxProfiler
->recordQueryCompletion(
1242 $queryProf, $startTime, $isWrite, $this->affectedRows()
1244 $this->queryLogger
->debug( $sql, [
1246 'master' => $isMaster,
1247 'runtime' => $queryRuntime,
1254 * Update the estimated run-time of a query, not counting large row lock times
1256 * LoadBalancer can be set to rollback transactions that will create huge replication
1257 * lag. It bases this estimate off of pendingWriteQueryDuration(). Certain simple
1258 * queries, like inserting a row can take a long time due to row locking. This method
1259 * uses some simple heuristics to discount those cases.
1261 * @param string $sql A SQL write query
1262 * @param float $runtime Total runtime, including RTT
1263 * @param int $affected Affected row count
1265 private function updateTrxWriteQueryTime( $sql, $runtime, $affected ) {
1266 // Whether this is indicative of replica DB runtime (except for RBR or ws_repl)
1267 $indicativeOfReplicaRuntime = true;
1268 if ( $runtime > self
::SLOW_WRITE_SEC
) {
1269 $verb = $this->getQueryVerb( $sql );
1270 // insert(), upsert(), replace() are fast unless bulky in size or blocked on locks
1271 if ( $verb === 'INSERT' ) {
1272 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
;
1273 } elseif ( $verb === 'REPLACE' ) {
1274 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
/ 2;
1278 $this->trxWriteDuration +
= $runtime;
1279 $this->trxWriteQueryCount +
= 1;
1280 $this->trxWriteAffectedRows +
= $affected;
1281 if ( $indicativeOfReplicaRuntime ) {
1282 $this->trxWriteAdjDuration +
= $runtime;
1283 $this->trxWriteAdjQueryCount +
= 1;
1288 * @param string $sql
1289 * @param string $fname
1290 * @throws DBTransactionStateError
1292 private function assertTransactionStatus( $sql, $fname ) {
1293 if ( $this->getQueryVerb( $sql ) === 'ROLLBACK' ) { // transaction/savepoint
1297 if ( $this->trxStatus
< self
::STATUS_TRX_OK
) {
1298 throw new DBTransactionStateError(
1300 "Cannot execute query from $fname while transaction status is ERROR.",
1302 $this->trxStatusCause
1304 } elseif ( $this->trxStatus
=== self
::STATUS_TRX_OK
&& $this->trxStatusIgnoredCause
) {
1305 list( $iLastError, $iLastErrno, $iFname ) = $this->trxStatusIgnoredCause
;
1306 call_user_func( $this->deprecationLogger
,
1307 "Caller from $fname ignored an error originally raised from $iFname: " .
1308 "[$iLastErrno] $iLastError"
1310 $this->trxStatusIgnoredCause
= null;
1315 * Determine whether or not it is safe to retry queries after a database
1316 * connection is lost
1318 * @param string $sql SQL query
1319 * @param bool $priorWritesPending Whether there is a transaction open with
1320 * possible write queries or transaction pre-commit/idle callbacks
1321 * waiting on it to finish.
1322 * @return bool True if it is safe to retry the query, false otherwise
1324 private function canRecoverFromDisconnect( $sql, $priorWritesPending ) {
1325 # Transaction dropped; this can mean lost writes, or REPEATABLE-READ snapshots.
1326 # Dropped connections also mean that named locks are automatically released.
1327 # Only allow error suppression in autocommit mode or when the lost transaction
1328 # didn't matter anyway (aside from DBO_TRX snapshot loss).
1329 if ( $this->namedLocksHeld
) {
1330 return false; // possible critical section violation
1331 } elseif ( $this->sessionTempTables
) {
1332 return false; // tables might be queried latter
1333 } elseif ( $sql === 'COMMIT' ) {
1334 return !$priorWritesPending; // nothing written anyway? (T127428)
1335 } elseif ( $sql === 'ROLLBACK' ) {
1336 return true; // transaction lost...which is also what was requested :)
1337 } elseif ( $this->explicitTrxActive() ) {
1338 return false; // don't drop atomocity and explicit snapshots
1339 } elseif ( $priorWritesPending ) {
1340 return false; // prior writes lost from implicit transaction
1347 * Clean things up after session (and thus transaction) loss
1349 private function handleSessionLoss() {
1350 // Clean up tracking of session-level things...
1351 // https://dev.mysql.com/doc/refman/5.7/en/implicit-commit.html
1352 // https://www.postgresql.org/docs/9.2/static/sql-createtable.html (ignoring ON COMMIT)
1353 $this->sessionTempTables
= [];
1354 // https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1355 // https://www.postgresql.org/docs/9.4/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1356 $this->namedLocksHeld
= [];
1357 // Session loss implies transaction loss
1358 $this->handleTransactionLoss();
1362 * Clean things up after transaction loss
1364 private function handleTransactionLoss() {
1365 $this->trxLevel
= 0;
1366 $this->trxAtomicCounter
= 0;
1367 $this->trxIdleCallbacks
= []; // T67263; transaction already lost
1368 $this->trxPreCommitCallbacks
= []; // T67263; transaction already lost
1370 // Handle callbacks in trxEndCallbacks, e.g. onTransactionResolution().
1371 // If callback suppression is set then the array will remain unhandled.
1372 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
1373 } catch ( Exception
$ex ) {
1374 // Already logged; move on...
1377 // Handle callbacks in trxRecurringCallbacks, e.g. setTransactionListener()
1378 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
1379 } catch ( Exception
$ex ) {
1380 // Already logged; move on...
1385 * Checks whether the cause of the error is detected to be a timeout.
1387 * It returns false by default, and not all engines support detecting this yet.
1388 * If this returns false, it will be treated as a generic query error.
1390 * @param string $error Error text
1391 * @param int $errno Error number
1394 protected function wasQueryTimeout( $error, $errno ) {
1399 * Report a query error. Log the error, and if neither the object ignore
1400 * flag nor the $tempIgnore flag is set, throw a DBQueryError.
1402 * @param string $error
1404 * @param string $sql
1405 * @param string $fname
1406 * @param bool $tempIgnore
1407 * @throws DBQueryError
1409 public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
1410 if ( $tempIgnore ) {
1411 $this->queryLogger
->debug( "SQL ERROR (ignored): $error\n" );
1413 $exception = $this->makeQueryException( $error, $errno, $sql, $fname );
1420 * @param string $error
1421 * @param string|int $errno
1422 * @param string $sql
1423 * @param string $fname
1426 private function makeQueryException( $error, $errno, $sql, $fname ) {
1427 $sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
1428 $this->queryLogger
->error(
1429 "{fname}\t{db_server}\t{errno}\t{error}\t{sql1line}",
1430 $this->getLogContext( [
1431 'method' => __METHOD__
,
1434 'sql1line' => $sql1line,
1438 $this->queryLogger
->debug( "SQL ERROR: " . $error . "\n" );
1439 $wasQueryTimeout = $this->wasQueryTimeout( $error, $errno );
1440 if ( $wasQueryTimeout ) {
1441 $e = new DBQueryTimeoutError( $this, $error, $errno, $sql, $fname );
1443 $e = new DBQueryError( $this, $error, $errno, $sql, $fname );
1449 public function freeResult( $res ) {
1452 public function selectField(
1453 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1455 if ( $var === '*' ) { // sanity
1456 throw new DBUnexpectedError( $this, "Cannot use a * field: got '$var'" );
1459 if ( !is_array( $options ) ) {
1460 $options = [ $options ];
1463 $options['LIMIT'] = 1;
1465 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1466 if ( $res === false ||
!$this->numRows( $res ) ) {
1470 $row = $this->fetchRow( $res );
1472 if ( $row !== false ) {
1473 return reset( $row );
1479 public function selectFieldValues(
1480 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1482 if ( $var === '*' ) { // sanity
1483 throw new DBUnexpectedError( $this, "Cannot use a * field" );
1484 } elseif ( !is_string( $var ) ) { // sanity
1485 throw new DBUnexpectedError( $this, "Cannot use an array of fields" );
1488 if ( !is_array( $options ) ) {
1489 $options = [ $options ];
1492 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1493 if ( $res === false ) {
1498 foreach ( $res as $row ) {
1499 $values[] = $row->$var;
1506 * Returns an optional USE INDEX clause to go after the table, and a
1507 * string to go at the end of the query.
1509 * @param array $options Associative array of options to be turned into
1510 * an SQL query, valid keys are listed in the function.
1512 * @see Database::select()
1514 protected function makeSelectOptions( $options ) {
1515 $preLimitTail = $postLimitTail = '';
1520 foreach ( $options as $key => $option ) {
1521 if ( is_numeric( $key ) ) {
1522 $noKeyOptions[$option] = true;
1526 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1528 $preLimitTail .= $this->makeOrderBy( $options );
1530 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1531 $postLimitTail .= ' FOR UPDATE';
1534 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1535 $postLimitTail .= ' LOCK IN SHARE MODE';
1538 if ( isset( $noKeyOptions['DISTINCT'] ) ||
isset( $noKeyOptions['DISTINCTROW'] ) ) {
1539 $startOpts .= 'DISTINCT';
1542 # Various MySQL extensions
1543 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) {
1544 $startOpts .= ' /*! STRAIGHT_JOIN */';
1547 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) {
1548 $startOpts .= ' HIGH_PRIORITY';
1551 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) {
1552 $startOpts .= ' SQL_BIG_RESULT';
1555 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) {
1556 $startOpts .= ' SQL_BUFFER_RESULT';
1559 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) {
1560 $startOpts .= ' SQL_SMALL_RESULT';
1563 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) {
1564 $startOpts .= ' SQL_CALC_FOUND_ROWS';
1567 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) {
1568 $startOpts .= ' SQL_CACHE';
1571 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) {
1572 $startOpts .= ' SQL_NO_CACHE';
1575 if ( isset( $options['USE INDEX'] ) && is_string( $options['USE INDEX'] ) ) {
1576 $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1580 if ( isset( $options['IGNORE INDEX'] ) && is_string( $options['IGNORE INDEX'] ) ) {
1581 $ignoreIndex = $this->ignoreIndexClause( $options['IGNORE INDEX'] );
1586 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1590 * Returns an optional GROUP BY with an optional HAVING
1592 * @param array $options Associative array of options
1594 * @see Database::select()
1597 protected function makeGroupByWithHaving( $options ) {
1599 if ( isset( $options['GROUP BY'] ) ) {
1600 $gb = is_array( $options['GROUP BY'] )
1601 ?
implode( ',', $options['GROUP BY'] )
1602 : $options['GROUP BY'];
1603 $sql .= ' GROUP BY ' . $gb;
1605 if ( isset( $options['HAVING'] ) ) {
1606 $having = is_array( $options['HAVING'] )
1607 ?
$this->makeList( $options['HAVING'], self
::LIST_AND
)
1608 : $options['HAVING'];
1609 $sql .= ' HAVING ' . $having;
1616 * Returns an optional ORDER BY
1618 * @param array $options Associative array of options
1620 * @see Database::select()
1623 protected function makeOrderBy( $options ) {
1624 if ( isset( $options['ORDER BY'] ) ) {
1625 $ob = is_array( $options['ORDER BY'] )
1626 ?
implode( ',', $options['ORDER BY'] )
1627 : $options['ORDER BY'];
1629 return ' ORDER BY ' . $ob;
1635 public function select(
1636 $table, $vars, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1638 $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
1640 return $this->query( $sql, $fname );
1643 public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__
,
1644 $options = [], $join_conds = []
1646 if ( is_array( $vars ) ) {
1647 $fields = implode( ',', $this->fieldNamesWithAlias( $vars ) );
1652 $options = (array)$options;
1653 $useIndexes = ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1654 ?
$options['USE INDEX']
1657 isset( $options['IGNORE INDEX'] ) &&
1658 is_array( $options['IGNORE INDEX'] )
1660 ?
$options['IGNORE INDEX']
1664 $this->selectOptionsIncludeLocking( $options ) &&
1665 $this->selectFieldsOrOptionsAggregate( $vars, $options )
1667 // Some DB types (postgres/oracle) disallow FOR UPDATE with aggregate
1668 // functions. Discourage use of such queries to encourage compatibility.
1670 $this->deprecationLogger
,
1671 __METHOD__
. ": aggregation used with a locking SELECT ($fname)."
1675 if ( is_array( $table ) ) {
1677 $this->tableNamesWithIndexClauseOrJOIN(
1678 $table, $useIndexes, $ignoreIndexes, $join_conds );
1679 } elseif ( $table != '' ) {
1681 $this->tableNamesWithIndexClauseOrJOIN(
1682 [ $table ], $useIndexes, $ignoreIndexes, [] );
1687 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ) =
1688 $this->makeSelectOptions( $options );
1690 if ( is_array( $conds ) ) {
1691 $conds = $this->makeList( $conds, self
::LIST_AND
);
1694 if ( $conds === null ||
$conds === false ) {
1695 $this->queryLogger
->warning(
1699 . ' with incorrect parameters: $conds must be a string or an array'
1704 if ( $conds === '' ) {
1705 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex $preLimitTail";
1706 } elseif ( is_string( $conds ) ) {
1707 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex " .
1708 "WHERE $conds $preLimitTail";
1710 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
1713 if ( isset( $options['LIMIT'] ) ) {
1714 $sql = $this->limitResult( $sql, $options['LIMIT'],
1715 $options['OFFSET'] ??
false );
1717 $sql = "$sql $postLimitTail";
1719 if ( isset( $options['EXPLAIN'] ) ) {
1720 $sql = 'EXPLAIN ' . $sql;
1726 public function selectRow( $table, $vars, $conds, $fname = __METHOD__
,
1727 $options = [], $join_conds = []
1729 $options = (array)$options;
1730 $options['LIMIT'] = 1;
1731 $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
1733 if ( $res === false ) {
1737 if ( !$this->numRows( $res ) ) {
1741 $obj = $this->fetchObject( $res );
1746 public function estimateRowCount(
1747 $table, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1749 $conds = $this->normalizeConditions( $conds, $fname );
1750 $column = $this->extractSingleFieldFromList( $var );
1751 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1752 $conds[] = "$column IS NOT NULL";
1755 $res = $this->select(
1756 $table, [ 'rowcount' => 'COUNT(*)' ], $conds, $fname, $options, $join_conds
1758 $row = $res ?
$this->fetchRow( $res ) : [];
1760 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1763 public function selectRowCount(
1764 $tables, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1766 $conds = $this->normalizeConditions( $conds, $fname );
1767 $column = $this->extractSingleFieldFromList( $var );
1768 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1769 $conds[] = "$column IS NOT NULL";
1772 $res = $this->select(
1774 'tmp_count' => $this->buildSelectSubquery(
1783 [ 'rowcount' => 'COUNT(*)' ],
1787 $row = $res ?
$this->fetchRow( $res ) : [];
1789 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1793 * @param string|array $options
1796 private function selectOptionsIncludeLocking( $options ) {
1797 $options = (array)$options;
1798 foreach ( [ 'FOR UPDATE', 'LOCK IN SHARE MODE' ] as $lock ) {
1799 if ( in_array( $lock, $options, true ) ) {
1808 * @param array|string $fields
1809 * @param array|string $options
1812 private function selectFieldsOrOptionsAggregate( $fields, $options ) {
1813 foreach ( (array)$options as $key => $value ) {
1814 if ( is_string( $key ) ) {
1815 if ( preg_match( '/^(?:GROUP BY|HAVING)$/i', $key ) ) {
1818 } elseif ( is_string( $value ) ) {
1819 if ( preg_match( '/^(?:DISTINCT|DISTINCTROW)$/i', $value ) ) {
1825 $regex = '/^(?:COUNT|MIN|MAX|SUM|GROUP_CONCAT|LISTAGG|ARRAY_AGG)\s*\\(/i';
1826 foreach ( (array)$fields as $field ) {
1827 if ( is_string( $field ) && preg_match( $regex, $field ) ) {
1836 * @param array|string $conds
1837 * @param string $fname
1840 final protected function normalizeConditions( $conds, $fname ) {
1841 if ( $conds === null ||
$conds === false ) {
1842 $this->queryLogger
->warning(
1846 . ' with incorrect parameters: $conds must be a string or an array'
1851 if ( !is_array( $conds ) ) {
1852 $conds = ( $conds === '' ) ?
[] : [ $conds ];
1859 * @param array|string $var Field parameter in the style of select()
1860 * @return string|null Column name or null; ignores aliases
1861 * @throws DBUnexpectedError Errors out if multiple columns are given
1863 final protected function extractSingleFieldFromList( $var ) {
1864 if ( is_array( $var ) ) {
1867 } elseif ( count( $var ) == 1 ) {
1868 $column = $var[0] ??
reset( $var );
1870 throw new DBUnexpectedError( $this, __METHOD__
. ': got multiple columns.' );
1879 public function lockForUpdate(
1880 $table, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1882 if ( !$this->trxLevel
&& !$this->getFlag( self
::DBO_TRX
) ) {
1883 throw new DBUnexpectedError(
1885 __METHOD__
. ': no transaction is active nor is DBO_TRX set'
1889 $options = (array)$options;
1890 $options[] = 'FOR UPDATE';
1892 return $this->selectRowCount( $table, '*', $conds, $fname, $options, $join_conds );
1896 * Removes most variables from an SQL query and replaces them with X or N for numbers.
1897 * It's only slightly flawed. Don't use for anything important.
1899 * @param string $sql A SQL Query
1903 protected static function generalizeSQL( $sql ) {
1904 # This does the same as the regexp below would do, but in such a way
1905 # as to avoid crashing php on some large strings.
1906 # $sql = preg_replace( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql );
1908 $sql = str_replace( "\\\\", '', $sql );
1909 $sql = str_replace( "\\'", '', $sql );
1910 $sql = str_replace( "\\\"", '', $sql );
1911 $sql = preg_replace( "/'.*'/s", "'X'", $sql );
1912 $sql = preg_replace( '/".*"/s', "'X'", $sql );
1914 # All newlines, tabs, etc replaced by single space
1915 $sql = preg_replace( '/\s+/', ' ', $sql );
1918 # except the ones surrounded by characters, e.g. l10n
1919 $sql = preg_replace( '/-?\d+(,-?\d+)+/s', 'N,...,N', $sql );
1920 $sql = preg_replace( '/(?<![a-zA-Z])-?\d+(?![a-zA-Z])/s', 'N', $sql );
1925 public function fieldExists( $table, $field, $fname = __METHOD__
) {
1926 $info = $this->fieldInfo( $table, $field );
1931 public function indexExists( $table, $index, $fname = __METHOD__
) {
1932 if ( !$this->tableExists( $table ) ) {
1936 $info = $this->indexInfo( $table, $index, $fname );
1937 if ( is_null( $info ) ) {
1940 return $info !== false;
1944 abstract public function tableExists( $table, $fname = __METHOD__
);
1946 public function indexUnique( $table, $index ) {
1947 $indexInfo = $this->indexInfo( $table, $index );
1949 if ( !$indexInfo ) {
1953 return !$indexInfo[0]->Non_unique
;
1957 * Helper for Database::insert().
1959 * @param array $options
1962 protected function makeInsertOptions( $options ) {
1963 return implode( ' ', $options );
1966 public function insert( $table, $a, $fname = __METHOD__
, $options = [] ) {
1967 # No rows to insert, easy just return now
1968 if ( !count( $a ) ) {
1972 $table = $this->tableName( $table );
1974 if ( !is_array( $options ) ) {
1975 $options = [ $options ];
1979 if ( isset( $options['fileHandle'] ) ) {
1980 $fh = $options['fileHandle'];
1982 $options = $this->makeInsertOptions( $options );
1984 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
1986 $keys = array_keys( $a[0] );
1989 $keys = array_keys( $a );
1992 $sql = 'INSERT ' . $options .
1993 " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
1997 foreach ( $a as $row ) {
2003 $sql .= '(' . $this->makeList( $row ) . ')';
2006 $sql .= '(' . $this->makeList( $a ) . ')';
2009 if ( $fh !== null && false === fwrite( $fh, $sql ) ) {
2011 } elseif ( $fh !== null ) {
2015 return (bool)$this->query( $sql, $fname );
2019 * Make UPDATE options array for Database::makeUpdateOptions
2021 * @param array $options
2024 protected function makeUpdateOptionsArray( $options ) {
2025 if ( !is_array( $options ) ) {
2026 $options = [ $options ];
2031 if ( in_array( 'IGNORE', $options ) ) {
2039 * Make UPDATE options for the Database::update function
2041 * @param array $options The options passed to Database::update
2044 protected function makeUpdateOptions( $options ) {
2045 $opts = $this->makeUpdateOptionsArray( $options );
2047 return implode( ' ', $opts );
2050 public function update( $table, $values, $conds, $fname = __METHOD__
, $options = [] ) {
2051 $table = $this->tableName( $table );
2052 $opts = $this->makeUpdateOptions( $options );
2053 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, self
::LIST_SET
);
2055 if ( $conds !== [] && $conds !== '*' ) {
2056 $sql .= " WHERE " . $this->makeList( $conds, self
::LIST_AND
);
2059 return (bool)$this->query( $sql, $fname );
2062 public function makeList( $a, $mode = self
::LIST_COMMA
) {
2063 if ( !is_array( $a ) ) {
2064 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
2070 foreach ( $a as $field => $value ) {
2072 if ( $mode == self
::LIST_AND
) {
2074 } elseif ( $mode == self
::LIST_OR
) {
2083 if ( ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_numeric( $field ) ) {
2084 $list .= "($value)";
2085 } elseif ( $mode == self
::LIST_SET
&& is_numeric( $field ) ) {
2088 ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_array( $value )
2090 // Remove null from array to be handled separately if found
2091 $includeNull = false;
2092 foreach ( array_keys( $value, null, true ) as $nullKey ) {
2093 $includeNull = true;
2094 unset( $value[$nullKey] );
2096 if ( count( $value ) == 0 && !$includeNull ) {
2097 throw new InvalidArgumentException(
2098 __METHOD__
. ": empty input for field $field" );
2099 } elseif ( count( $value ) == 0 ) {
2100 // only check if $field is null
2101 $list .= "$field IS NULL";
2103 // IN clause contains at least one valid element
2104 if ( $includeNull ) {
2105 // Group subconditions to ensure correct precedence
2108 if ( count( $value ) == 1 ) {
2109 // Special-case single values, as IN isn't terribly efficient
2110 // Don't necessarily assume the single key is 0; we don't
2111 // enforce linear numeric ordering on other arrays here.
2112 $value = array_values( $value )[0];
2113 $list .= $field . " = " . $this->addQuotes( $value );
2115 $list .= $field . " IN (" . $this->makeList( $value ) . ") ";
2117 // if null present in array, append IS NULL
2118 if ( $includeNull ) {
2119 $list .= " OR $field IS NULL)";
2122 } elseif ( $value === null ) {
2123 if ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) {
2124 $list .= "$field IS ";
2125 } elseif ( $mode == self
::LIST_SET
) {
2126 $list .= "$field = ";
2131 $mode == self
::LIST_AND ||
$mode == self
::LIST_OR ||
$mode == self
::LIST_SET
2133 $list .= "$field = ";
2135 $list .= $mode == self
::LIST_NAMES ?
$value : $this->addQuotes( $value );
2142 public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
2145 foreach ( $data as $base => $sub ) {
2146 if ( count( $sub ) ) {
2147 $conds[] = $this->makeList(
2148 [ $baseKey => $base, $subKey => array_keys( $sub ) ],
2154 return $this->makeList( $conds, self
::LIST_OR
);
2156 // Nothing to search for...
2161 public function aggregateValue( $valuedata, $valuename = 'value' ) {
2165 public function bitNot( $field ) {
2169 public function bitAnd( $fieldLeft, $fieldRight ) {
2170 return "($fieldLeft & $fieldRight)";
2173 public function bitOr( $fieldLeft, $fieldRight ) {
2174 return "($fieldLeft | $fieldRight)";
2177 public function buildConcat( $stringList ) {
2178 return 'CONCAT(' . implode( ',', $stringList ) . ')';
2181 public function buildGroupConcatField(
2182 $delim, $table, $field, $conds = '', $join_conds = []
2184 $fld = "GROUP_CONCAT($field SEPARATOR " . $this->addQuotes( $delim ) . ')';
2186 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
2189 public function buildSubstring( $input, $startPosition, $length = null ) {
2190 $this->assertBuildSubstringParams( $startPosition, $length );
2191 $functionBody = "$input FROM $startPosition";
2192 if ( $length !== null ) {
2193 $functionBody .= " FOR $length";
2195 return 'SUBSTRING(' . $functionBody . ')';
2199 * Check type and bounds for parameters to self::buildSubstring()
2201 * All supported databases have substring functions that behave the same for
2202 * positive $startPosition and non-negative $length, but behaviors differ when
2203 * given 0 or negative $startPosition or negative $length. The simplest
2204 * solution to that is to just forbid those values.
2206 * @param int $startPosition
2207 * @param int|null $length
2210 protected function assertBuildSubstringParams( $startPosition, $length ) {
2211 if ( !is_int( $startPosition ) ||
$startPosition <= 0 ) {
2212 throw new InvalidArgumentException(
2213 '$startPosition must be a positive integer'
2216 if ( !( is_int( $length ) && $length >= 0 ||
$length === null ) ) {
2217 throw new InvalidArgumentException(
2218 '$length must be null or an integer greater than or equal to 0'
2223 public function buildStringCast( $field ) {
2227 public function buildIntegerCast( $field ) {
2228 return 'CAST( ' . $field . ' AS INTEGER )';
2231 public function buildSelectSubquery(
2232 $table, $vars, $conds = '', $fname = __METHOD__
,
2233 $options = [], $join_conds = []
2235 return new Subquery(
2236 $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds )
2240 public function databasesAreIndependent() {
2244 public function selectDB( $db ) {
2245 # Stub. Shouldn't cause serious problems if it's not overridden, but
2246 # if your database engine supports a concept similar to MySQL's
2247 # databases you may as well.
2248 $this->dbName
= $db;
2253 public function getDBname() {
2254 return $this->dbName
;
2257 public function getServer() {
2258 return $this->server
;
2261 public function tableName( $name, $format = 'quoted' ) {
2262 if ( $name instanceof Subquery
) {
2263 throw new DBUnexpectedError(
2265 __METHOD__
. ': got Subquery instance when expecting a string.'
2269 # Skip the entire process when we have a string quoted on both ends.
2270 # Note that we check the end so that we will still quote any use of
2271 # use of `database`.table. But won't break things if someone wants
2272 # to query a database table with a dot in the name.
2273 if ( $this->isQuotedIdentifier( $name ) ) {
2277 # Lets test for any bits of text that should never show up in a table
2278 # name. Basically anything like JOIN or ON which are actually part of
2279 # SQL queries, but may end up inside of the table value to combine
2280 # sql. Such as how the API is doing.
2281 # Note that we use a whitespace test rather than a \b test to avoid
2282 # any remote case where a word like on may be inside of a table name
2283 # surrounded by symbols which may be considered word breaks.
2284 if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) {
2285 $this->queryLogger
->warning(
2286 __METHOD__
. ": use of subqueries is not supported this way.",
2287 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
2293 # Split database and table into proper variables.
2294 list( $database, $schema, $prefix, $table ) = $this->qualifiedTableComponents( $name );
2296 # Quote $table and apply the prefix if not quoted.
2297 # $tableName might be empty if this is called from Database::replaceVars()
2298 $tableName = "{$prefix}{$table}";
2299 if ( $format === 'quoted'
2300 && !$this->isQuotedIdentifier( $tableName )
2301 && $tableName !== ''
2303 $tableName = $this->addIdentifierQuotes( $tableName );
2306 # Quote $schema and $database and merge them with the table name if needed
2307 $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
2308 $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
2314 * Get the table components needed for a query given the currently selected database
2316 * @param string $name Table name in the form of db.schema.table, db.table, or table
2317 * @return array (DB name or "" for default, schema name, table prefix, table name)
2319 protected function qualifiedTableComponents( $name ) {
2320 # We reverse the explode so that database.table and table both output the correct table.
2321 $dbDetails = explode( '.', $name, 3 );
2322 if ( count( $dbDetails ) == 3 ) {
2323 list( $database, $schema, $table ) = $dbDetails;
2324 # We don't want any prefix added in this case
2326 } elseif ( count( $dbDetails ) == 2 ) {
2327 list( $database, $table ) = $dbDetails;
2328 # We don't want any prefix added in this case
2330 # In dbs that support it, $database may actually be the schema
2331 # but that doesn't affect any of the functionality here
2334 list( $table ) = $dbDetails;
2335 if ( isset( $this->tableAliases
[$table] ) ) {
2336 $database = $this->tableAliases
[$table]['dbname'];
2337 $schema = is_string( $this->tableAliases
[$table]['schema'] )
2338 ?
$this->tableAliases
[$table]['schema']
2340 $prefix = is_string( $this->tableAliases
[$table]['prefix'] )
2341 ?
$this->tableAliases
[$table]['prefix']
2342 : $this->tablePrefix
;
2345 $schema = $this->schema
; # Default schema
2346 $prefix = $this->tablePrefix
; # Default prefix
2350 return [ $database, $schema, $prefix, $table ];
2354 * @param string|null $namespace Database or schema
2355 * @param string $relation Name of table, view, sequence, etc...
2356 * @param string $format One of (raw, quoted)
2357 * @return string Relation name with quoted and merged $namespace as needed
2359 private function prependDatabaseOrSchema( $namespace, $relation, $format ) {
2360 if ( strlen( $namespace ) ) {
2361 if ( $format === 'quoted' && !$this->isQuotedIdentifier( $namespace ) ) {
2362 $namespace = $this->addIdentifierQuotes( $namespace );
2364 $relation = $namespace . '.' . $relation;
2370 public function tableNames() {
2371 $inArray = func_get_args();
2374 foreach ( $inArray as $name ) {
2375 $retVal[$name] = $this->tableName( $name );
2381 public function tableNamesN() {
2382 $inArray = func_get_args();
2385 foreach ( $inArray as $name ) {
2386 $retVal[] = $this->tableName( $name );
2393 * Get an aliased table name
2395 * This returns strings like "tableName AS newTableName" for aliased tables
2396 * and "(SELECT * from tableA) newTablename" for subqueries (e.g. derived tables)
2398 * @see Database::tableName()
2399 * @param string|Subquery $table Table name or object with a 'sql' field
2400 * @param string|bool $alias Table alias (optional)
2401 * @return string SQL name for aliased table. Will not alias a table to its own name
2403 protected function tableNameWithAlias( $table, $alias = false ) {
2404 if ( is_string( $table ) ) {
2405 $quotedTable = $this->tableName( $table );
2406 } elseif ( $table instanceof Subquery
) {
2407 $quotedTable = (string)$table;
2409 throw new InvalidArgumentException( "Table must be a string or Subquery." );
2412 if ( !strlen( $alias ) ||
$alias === $table ) {
2413 if ( $table instanceof Subquery
) {
2414 throw new InvalidArgumentException( "Subquery table missing alias." );
2417 return $quotedTable;
2419 return $quotedTable . ' ' . $this->addIdentifierQuotes( $alias );
2424 * Gets an array of aliased table names
2426 * @param array $tables [ [alias] => table ]
2427 * @return string[] See tableNameWithAlias()
2429 protected function tableNamesWithAlias( $tables ) {
2431 foreach ( $tables as $alias => $table ) {
2432 if ( is_numeric( $alias ) ) {
2435 $retval[] = $this->tableNameWithAlias( $table, $alias );
2442 * Get an aliased field name
2443 * e.g. fieldName AS newFieldName
2445 * @param string $name Field name
2446 * @param string|bool $alias Alias (optional)
2447 * @return string SQL name for aliased field. Will not alias a field to its own name
2449 protected function fieldNameWithAlias( $name, $alias = false ) {
2450 if ( !$alias ||
(string)$alias === (string)$name ) {
2453 return $name . ' AS ' . $this->addIdentifierQuotes( $alias ); // PostgreSQL needs AS
2458 * Gets an array of aliased field names
2460 * @param array $fields [ [alias] => field ]
2461 * @return string[] See fieldNameWithAlias()
2463 protected function fieldNamesWithAlias( $fields ) {
2465 foreach ( $fields as $alias => $field ) {
2466 if ( is_numeric( $alias ) ) {
2469 $retval[] = $this->fieldNameWithAlias( $field, $alias );
2476 * Get the aliased table name clause for a FROM clause
2477 * which might have a JOIN and/or USE INDEX or IGNORE INDEX clause
2479 * @param array $tables ( [alias] => table )
2480 * @param array $use_index Same as for select()
2481 * @param array $ignore_index Same as for select()
2482 * @param array $join_conds Same as for select()
2485 protected function tableNamesWithIndexClauseOrJOIN(
2486 $tables, $use_index = [], $ignore_index = [], $join_conds = []
2490 $use_index = (array)$use_index;
2491 $ignore_index = (array)$ignore_index;
2492 $join_conds = (array)$join_conds;
2494 foreach ( $tables as $alias => $table ) {
2495 if ( !is_string( $alias ) ) {
2496 // No alias? Set it equal to the table name
2500 if ( is_array( $table ) ) {
2501 // A parenthesized group
2502 if ( count( $table ) > 1 ) {
2503 $joinedTable = '(' .
2504 $this->tableNamesWithIndexClauseOrJOIN(
2505 $table, $use_index, $ignore_index, $join_conds ) . ')';
2508 $innerTable = reset( $table );
2509 $innerAlias = key( $table );
2510 $joinedTable = $this->tableNameWithAlias(
2512 is_string( $innerAlias ) ?
$innerAlias : $innerTable
2516 $joinedTable = $this->tableNameWithAlias( $table, $alias );
2519 // Is there a JOIN clause for this table?
2520 if ( isset( $join_conds[$alias] ) ) {
2521 list( $joinType, $conds ) = $join_conds[$alias];
2522 $tableClause = $joinType;
2523 $tableClause .= ' ' . $joinedTable;
2524 if ( isset( $use_index[$alias] ) ) { // has USE INDEX?
2525 $use = $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) );
2527 $tableClause .= ' ' . $use;
2530 if ( isset( $ignore_index[$alias] ) ) { // has IGNORE INDEX?
2531 $ignore = $this->ignoreIndexClause(
2532 implode( ',', (array)$ignore_index[$alias] ) );
2533 if ( $ignore != '' ) {
2534 $tableClause .= ' ' . $ignore;
2537 $on = $this->makeList( (array)$conds, self
::LIST_AND
);
2539 $tableClause .= ' ON (' . $on . ')';
2542 $retJOIN[] = $tableClause;
2543 } elseif ( isset( $use_index[$alias] ) ) {
2544 // Is there an INDEX clause for this table?
2545 $tableClause = $joinedTable;
2546 $tableClause .= ' ' . $this->useIndexClause(
2547 implode( ',', (array)$use_index[$alias] )
2550 $ret[] = $tableClause;
2551 } elseif ( isset( $ignore_index[$alias] ) ) {
2552 // Is there an INDEX clause for this table?
2553 $tableClause = $joinedTable;
2554 $tableClause .= ' ' . $this->ignoreIndexClause(
2555 implode( ',', (array)$ignore_index[$alias] )
2558 $ret[] = $tableClause;
2560 $tableClause = $joinedTable;
2562 $ret[] = $tableClause;
2566 // We can't separate explicit JOIN clauses with ',', use ' ' for those
2567 $implicitJoins = $ret ?
implode( ',', $ret ) : "";
2568 $explicitJoins = $retJOIN ?
implode( ' ', $retJOIN ) : "";
2570 // Compile our final table clause
2571 return implode( ' ', [ $implicitJoins, $explicitJoins ] );
2575 * Allows for index remapping in queries where this is not consistent across DBMS
2577 * @param string $index
2580 protected function indexName( $index ) {
2581 return $this->indexAliases
[$index] ??
$index;
2584 public function addQuotes( $s ) {
2585 if ( $s instanceof Blob
) {
2588 if ( $s === null ) {
2590 } elseif ( is_bool( $s ) ) {
2593 # This will also quote numeric values. This should be harmless,
2594 # and protects against weird problems that occur when they really
2595 # _are_ strings such as article titles and string->number->string
2596 # conversion is not 1:1.
2597 return "'" . $this->strencode( $s ) . "'";
2602 * Quotes an identifier using `backticks` or "double quotes" depending on the database type.
2603 * MySQL uses `backticks` while basically everything else uses double quotes.
2604 * Since MySQL is the odd one out here the double quotes are our generic
2605 * and we implement backticks in DatabaseMysqlBase.
2610 public function addIdentifierQuotes( $s ) {
2611 return '"' . str_replace( '"', '""', $s ) . '"';
2615 * Returns if the given identifier looks quoted or not according to
2616 * the database convention for quoting identifiers .
2618 * @note Do not use this to determine if untrusted input is safe.
2619 * A malicious user can trick this function.
2620 * @param string $name
2623 public function isQuotedIdentifier( $name ) {
2624 return $name[0] == '"' && substr( $name, -1, 1 ) == '"';
2629 * @param string $escapeChar
2632 protected function escapeLikeInternal( $s, $escapeChar = '`' ) {
2633 return str_replace( [ $escapeChar, '%', '_' ],
2634 [ "{$escapeChar}{$escapeChar}", "{$escapeChar}%", "{$escapeChar}_" ],
2638 public function buildLike() {
2639 $params = func_get_args();
2641 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
2642 $params = $params[0];
2647 // We use ` instead of \ as the default LIKE escape character, since addQuotes()
2648 // may escape backslashes, creating problems of double escaping. The `
2649 // character has good cross-DBMS compatibility, avoiding special operators
2650 // in MS SQL like ^ and %
2653 foreach ( $params as $value ) {
2654 if ( $value instanceof LikeMatch
) {
2655 $s .= $value->toString();
2657 $s .= $this->escapeLikeInternal( $value, $escapeChar );
2662 $this->addQuotes( $s ) . ' ESCAPE ' . $this->addQuotes( $escapeChar ) . ' ';
2665 public function anyChar() {
2666 return new LikeMatch( '_' );
2669 public function anyString() {
2670 return new LikeMatch( '%' );
2673 public function nextSequenceValue( $seqName ) {
2678 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
2679 * is only needed because a) MySQL must be as efficient as possible due to
2680 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2681 * which index to pick. Anyway, other databases might have different
2682 * indexes on a given table. So don't bother overriding this unless you're
2684 * @param string $index
2687 public function useIndexClause( $index ) {
2692 * IGNORE INDEX clause. Unlikely to be useful for anything but MySQL. This
2693 * is only needed because a) MySQL must be as efficient as possible due to
2694 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2695 * which index to pick. Anyway, other databases might have different
2696 * indexes on a given table. So don't bother overriding this unless you're
2698 * @param string $index
2701 public function ignoreIndexClause( $index ) {
2705 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__
) {
2706 if ( count( $rows ) == 0 ) {
2711 if ( !is_array( reset( $rows ) ) ) {
2716 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2717 $affectedRowCount = 0;
2718 foreach ( $rows as $row ) {
2719 // Delete rows which collide with this one
2720 $indexWhereClauses = [];
2721 foreach ( $uniqueIndexes as $index ) {
2722 $indexColumns = (array)$index;
2723 $indexRowValues = array_intersect_key( $row, array_flip( $indexColumns ) );
2724 if ( count( $indexRowValues ) != count( $indexColumns ) ) {
2725 throw new DBUnexpectedError(
2727 'New record does not provide all values for unique key (' .
2728 implode( ', ', $indexColumns ) . ')'
2730 } elseif ( in_array( null, $indexRowValues, true ) ) {
2731 throw new DBUnexpectedError(
2733 'New record has a null value for unique key (' .
2734 implode( ', ', $indexColumns ) . ')'
2737 $indexWhereClauses[] = $this->makeList( $indexRowValues, LIST_AND
);
2740 if ( $indexWhereClauses ) {
2741 $this->delete( $table, $this->makeList( $indexWhereClauses, LIST_OR
), $fname );
2742 $affectedRowCount +
= $this->affectedRows();
2745 // Now insert the row
2746 $this->insert( $table, $row, $fname );
2747 $affectedRowCount +
= $this->affectedRows();
2749 $this->endAtomic( $fname );
2750 $this->affectedRowCount
= $affectedRowCount;
2751 } catch ( Exception
$e ) {
2752 $this->cancelAtomic( $fname );
2758 * REPLACE query wrapper for MySQL and SQLite, which have a native REPLACE
2761 * @param string $table Table name
2762 * @param array|string $rows Row(s) to insert
2763 * @param string $fname Caller function name
2765 * @return ResultWrapper
2767 protected function nativeReplace( $table, $rows, $fname ) {
2768 $table = $this->tableName( $table );
2771 if ( !is_array( reset( $rows ) ) ) {
2775 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES ';
2778 foreach ( $rows as $row ) {
2785 $sql .= '(' . $this->makeList( $row ) . ')';
2788 return $this->query( $sql, $fname );
2791 public function upsert( $table, array $rows, array $uniqueIndexes, array $set,
2794 if ( !count( $rows ) ) {
2795 return true; // nothing to do
2798 if ( !is_array( reset( $rows ) ) ) {
2802 if ( count( $uniqueIndexes ) ) {
2803 $clauses = []; // list WHERE clauses that each identify a single row
2804 foreach ( $rows as $row ) {
2805 foreach ( $uniqueIndexes as $index ) {
2806 $index = is_array( $index ) ?
$index : [ $index ]; // columns
2807 $rowKey = []; // unique key to this row
2808 foreach ( $index as $column ) {
2809 $rowKey[$column] = $row[$column];
2811 $clauses[] = $this->makeList( $rowKey, self
::LIST_AND
);
2814 $where = [ $this->makeList( $clauses, self
::LIST_OR
) ];
2819 $affectedRowCount = 0;
2821 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2822 # Update any existing conflicting row(s)
2823 if ( $where !== false ) {
2824 $ok = $this->update( $table, $set, $where, $fname );
2825 $affectedRowCount +
= $this->affectedRows();
2829 # Now insert any non-conflicting row(s)
2830 $ok = $this->insert( $table, $rows, $fname, [ 'IGNORE' ] ) && $ok;
2831 $affectedRowCount +
= $this->affectedRows();
2832 $this->endAtomic( $fname );
2833 $this->affectedRowCount
= $affectedRowCount;
2834 } catch ( Exception
$e ) {
2835 $this->cancelAtomic( $fname );
2842 public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
2846 throw new DBUnexpectedError( $this, __METHOD__
. ' called with empty $conds' );
2849 $delTable = $this->tableName( $delTable );
2850 $joinTable = $this->tableName( $joinTable );
2851 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
2852 if ( $conds != '*' ) {
2853 $sql .= 'WHERE ' . $this->makeList( $conds, self
::LIST_AND
);
2857 $this->query( $sql, $fname );
2860 public function textFieldSize( $table, $field ) {
2861 $table = $this->tableName( $table );
2862 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
2863 $res = $this->query( $sql, __METHOD__
);
2864 $row = $this->fetchObject( $res );
2868 if ( preg_match( '/\((.*)\)/', $row->Type
, $m ) ) {
2877 public function delete( $table, $conds, $fname = __METHOD__
) {
2879 throw new DBUnexpectedError( $this, __METHOD__
. ' called with no conditions' );
2882 $table = $this->tableName( $table );
2883 $sql = "DELETE FROM $table";
2885 if ( $conds != '*' ) {
2886 if ( is_array( $conds ) ) {
2887 $conds = $this->makeList( $conds, self
::LIST_AND
);
2889 $sql .= ' WHERE ' . $conds;
2892 return $this->query( $sql, $fname );
2895 final public function insertSelect(
2896 $destTable, $srcTable, $varMap, $conds,
2897 $fname = __METHOD__
, $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2899 static $hints = [ 'NO_AUTO_COLUMNS' ];
2901 $insertOptions = (array)$insertOptions;
2902 $selectOptions = (array)$selectOptions;
2904 if ( $this->cliMode
&& $this->isInsertSelectSafe( $insertOptions, $selectOptions ) ) {
2905 // For massive migrations with downtime, we don't want to select everything
2906 // into memory and OOM, so do all this native on the server side if possible.
2907 return $this->nativeInsertSelect(
2913 array_diff( $insertOptions, $hints ),
2919 return $this->nonNativeInsertSelect(
2925 array_diff( $insertOptions, $hints ),
2932 * @param array $insertOptions INSERT options
2933 * @param array $selectOptions SELECT options
2934 * @return bool Whether an INSERT SELECT with these options will be replication safe
2937 protected function isInsertSelectSafe( array $insertOptions, array $selectOptions ) {
2942 * Implementation of insertSelect() based on select() and insert()
2944 * @see IDatabase::insertSelect()
2946 * @param string $destTable
2947 * @param string|array $srcTable
2948 * @param array $varMap
2949 * @param array $conds
2950 * @param string $fname
2951 * @param array $insertOptions
2952 * @param array $selectOptions
2953 * @param array $selectJoinConds
2956 protected function nonNativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
2957 $fname = __METHOD__
,
2958 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2960 // For web requests, do a locking SELECT and then INSERT. This puts the SELECT burden
2961 // on only the master (without needing row-based-replication). It also makes it easy to
2962 // know how big the INSERT is going to be.
2964 foreach ( $varMap as $dstColumn => $sourceColumnOrSql ) {
2965 $fields[] = $this->fieldNameWithAlias( $sourceColumnOrSql, $dstColumn );
2967 $selectOptions[] = 'FOR UPDATE';
2968 $res = $this->select(
2969 $srcTable, implode( ',', $fields ), $conds, $fname, $selectOptions, $selectJoinConds
2976 $affectedRowCount = 0;
2977 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2980 foreach ( $res as $row ) {
2981 $rows[] = (array)$row;
2983 // Avoid inserts that are too huge
2984 if ( count( $rows ) >= $this->nonNativeInsertSelectBatchSize
) {
2985 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
2989 $affectedRowCount +
= $this->affectedRows();
2993 if ( $rows && $ok ) {
2994 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
2996 $affectedRowCount +
= $this->affectedRows();
3000 $this->endAtomic( $fname );
3001 $this->affectedRowCount
= $affectedRowCount;
3003 $this->cancelAtomic( $fname );
3006 } catch ( Exception
$e ) {
3007 $this->cancelAtomic( $fname );
3013 * Native server-side implementation of insertSelect() for situations where
3014 * we don't want to select everything into memory
3016 * @see IDatabase::insertSelect()
3017 * @param string $destTable
3018 * @param string|array $srcTable
3019 * @param array $varMap
3020 * @param array $conds
3021 * @param string $fname
3022 * @param array $insertOptions
3023 * @param array $selectOptions
3024 * @param array $selectJoinConds
3027 protected function nativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3028 $fname = __METHOD__
,
3029 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3031 $destTable = $this->tableName( $destTable );
3033 if ( !is_array( $insertOptions ) ) {
3034 $insertOptions = [ $insertOptions ];
3037 $insertOptions = $this->makeInsertOptions( $insertOptions );
3039 $selectSql = $this->selectSQLText(
3041 array_values( $varMap ),
3048 $sql = "INSERT $insertOptions" .
3049 " INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ') ' .
3052 return $this->query( $sql, $fname );
3056 * Construct a LIMIT query with optional offset. This is used for query
3057 * pages. The SQL should be adjusted so that only the first $limit rows
3058 * are returned. If $offset is provided as well, then the first $offset
3059 * rows should be discarded, and the next $limit rows should be returned.
3060 * If the result of the query is not ordered, then the rows to be returned
3061 * are theoretically arbitrary.
3063 * $sql is expected to be a SELECT, if that makes a difference.
3065 * The version provided by default works in MySQL and SQLite. It will very
3066 * likely need to be overridden for most other DBMSes.
3068 * @param string $sql SQL query we will append the limit too
3069 * @param int $limit The SQL limit
3070 * @param int|bool $offset The SQL offset (default false)
3071 * @throws DBUnexpectedError
3074 public function limitResult( $sql, $limit, $offset = false ) {
3075 if ( !is_numeric( $limit ) ) {
3076 throw new DBUnexpectedError( $this,
3077 "Invalid non-numeric limit passed to limitResult()\n" );
3080 return "$sql LIMIT "
3081 . ( ( is_numeric( $offset ) && $offset != 0 ) ?
"{$offset}," : "" )
3085 public function unionSupportsOrderAndLimit() {
3086 return true; // True for almost every DB supported
3089 public function unionQueries( $sqls, $all ) {
3090 $glue = $all ?
') UNION ALL (' : ') UNION (';
3092 return '(' . implode( $glue, $sqls ) . ')';
3095 public function unionConditionPermutations(
3096 $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__
,
3097 $options = [], $join_conds = []
3099 // First, build the Cartesian product of $permute_conds
3101 foreach ( $permute_conds as $field => $values ) {
3103 // Skip empty $values
3106 $values = array_unique( $values ); // For sanity
3108 foreach ( $conds as $cond ) {
3109 foreach ( $values as $value ) {
3110 $cond[$field] = $value;
3111 $newConds[] = $cond; // Arrays are by-value, not by-reference, so this works
3117 $extra_conds = $extra_conds === '' ?
[] : (array)$extra_conds;
3119 // If there's just one condition and no subordering, hand off to
3120 // selectSQLText directly.
3121 if ( count( $conds ) === 1 &&
3122 ( !isset( $options['INNER ORDER BY'] ) ||
!$this->unionSupportsOrderAndLimit() )
3124 return $this->selectSQLText(
3125 $table, $vars, $conds[0] +
$extra_conds, $fname, $options, $join_conds
3129 // Otherwise, we need to pull out the order and limit to apply after
3130 // the union. Then build the SQL queries for each set of conditions in
3131 // $conds. Then union them together (using UNION ALL, because the
3132 // product *should* already be distinct).
3133 $orderBy = $this->makeOrderBy( $options );
3134 $limit = $options['LIMIT'] ??
null;
3135 $offset = $options['OFFSET'] ??
false;
3136 $all = empty( $options['NOTALL'] ) && !in_array( 'NOTALL', $options );
3137 if ( !$this->unionSupportsOrderAndLimit() ) {
3138 unset( $options['ORDER BY'], $options['LIMIT'], $options['OFFSET'] );
3140 if ( array_key_exists( 'INNER ORDER BY', $options ) ) {
3141 $options['ORDER BY'] = $options['INNER ORDER BY'];
3143 if ( $limit !== null && is_numeric( $offset ) && $offset != 0 ) {
3144 // We need to increase the limit by the offset rather than
3145 // using the offset directly, otherwise it'll skip incorrectly
3146 // in the subqueries.
3147 $options['LIMIT'] = $limit +
$offset;
3148 unset( $options['OFFSET'] );
3153 foreach ( $conds as $cond ) {
3154 $sqls[] = $this->selectSQLText(
3155 $table, $vars, $cond +
$extra_conds, $fname, $options, $join_conds
3158 $sql = $this->unionQueries( $sqls, $all ) . $orderBy;
3159 if ( $limit !== null ) {
3160 $sql = $this->limitResult( $sql, $limit, $offset );
3166 public function conditional( $cond, $trueVal, $falseVal ) {
3167 if ( is_array( $cond ) ) {
3168 $cond = $this->makeList( $cond, self
::LIST_AND
);
3171 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
3174 public function strreplace( $orig, $old, $new ) {
3175 return "REPLACE({$orig}, {$old}, {$new})";
3178 public function getServerUptime() {
3182 public function wasDeadlock() {
3186 public function wasLockTimeout() {
3190 public function wasConnectionLoss() {
3191 return $this->wasConnectionError( $this->lastErrno() );
3194 public function wasReadOnlyError() {
3198 public function wasErrorReissuable() {
3200 $this->wasDeadlock() ||
3201 $this->wasLockTimeout() ||
3202 $this->wasConnectionLoss()
3207 * Do not use this method outside of Database/DBError classes
3209 * @param int|string $errno
3210 * @return bool Whether the given query error was a connection drop
3212 public function wasConnectionError( $errno ) {
3217 * @return bool Whether it is safe to assume the given error only caused statement rollback
3218 * @note This is for backwards compatibility for callers catching DBError exceptions in
3219 * order to ignore problems like duplicate key errors or foriegn key violations
3222 protected function wasKnownStatementRollbackError() {
3223 return false; // don't know; it could have caused a transaction rollback
3226 public function deadlockLoop() {
3227 $args = func_get_args();
3228 $function = array_shift( $args );
3229 $tries = self
::DEADLOCK_TRIES
;
3231 $this->begin( __METHOD__
);
3234 /** @var Exception $e */
3238 $retVal = $function( ...$args );
3240 } catch ( DBQueryError
$e ) {
3241 if ( $this->wasDeadlock() ) {
3242 // Retry after a randomized delay
3243 usleep( mt_rand( self
::DEADLOCK_DELAY_MIN
, self
::DEADLOCK_DELAY_MAX
) );
3245 // Throw the error back up
3249 } while ( --$tries > 0 );
3251 if ( $tries <= 0 ) {
3252 // Too many deadlocks; give up
3253 $this->rollback( __METHOD__
);
3256 $this->commit( __METHOD__
);
3262 public function masterPosWait( DBMasterPos
$pos, $timeout ) {
3263 # Real waits are implemented in the subclass.
3267 public function getReplicaPos() {
3272 public function getMasterPos() {
3277 public function serverIsReadOnly() {
3281 final public function onTransactionResolution( callable
$callback, $fname = __METHOD__
) {
3282 if ( !$this->trxLevel
) {
3283 throw new DBUnexpectedError( $this, "No transaction is active." );
3285 $this->trxEndCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3288 final public function onTransactionCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3289 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3290 // Start an implicit transaction similar to how query() does
3291 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3292 $this->trxAutomatic
= true;
3295 $this->trxIdleCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3296 if ( !$this->trxLevel
) {
3297 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_IDLE
);
3301 final public function onTransactionIdle( callable
$callback, $fname = __METHOD__
) {
3302 $this->onTransactionCommitOrIdle( $callback, $fname );
3305 final public function onTransactionPreCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3306 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3307 // Start an implicit transaction similar to how query() does
3308 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3309 $this->trxAutomatic
= true;
3312 if ( $this->trxLevel
) {
3313 $this->trxPreCommitCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3315 // No transaction is active nor will start implicitly, so make one for this callback
3316 $this->startAtomic( __METHOD__
, self
::ATOMIC_CANCELABLE
);
3319 $this->endAtomic( __METHOD__
);
3320 } catch ( Exception
$e ) {
3321 $this->cancelAtomic( __METHOD__
);
3328 * @return AtomicSectionIdentifier|null ID of the topmost atomic section level
3330 private function currentAtomicSectionId() {
3331 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3332 $levelInfo = end( $this->trxAtomicLevels
);
3334 return $levelInfo[1];
3341 * @param AtomicSectionIdentifier $old
3342 * @param AtomicSectionIdentifier $new
3344 private function reassignCallbacksForSection(
3345 AtomicSectionIdentifier
$old, AtomicSectionIdentifier
$new
3347 foreach ( $this->trxPreCommitCallbacks
as $key => $info ) {
3348 if ( $info[2] === $old ) {
3349 $this->trxPreCommitCallbacks
[$key][2] = $new;
3352 foreach ( $this->trxIdleCallbacks
as $key => $info ) {
3353 if ( $info[2] === $old ) {
3354 $this->trxIdleCallbacks
[$key][2] = $new;
3357 foreach ( $this->trxEndCallbacks
as $key => $info ) {
3358 if ( $info[2] === $old ) {
3359 $this->trxEndCallbacks
[$key][2] = $new;
3365 * @param AtomicSectionIdentifier[] $sectionIds ID of an actual savepoint
3366 * @throws UnexpectedValueException
3368 private function modifyCallbacksForCancel( array $sectionIds ) {
3369 // Cancel the "on commit" callbacks owned by this savepoint
3370 $this->trxIdleCallbacks
= array_filter(
3371 $this->trxIdleCallbacks
,
3372 function ( $entry ) use ( $sectionIds ) {
3373 return !in_array( $entry[2], $sectionIds, true );
3376 $this->trxPreCommitCallbacks
= array_filter(
3377 $this->trxPreCommitCallbacks
,
3378 function ( $entry ) use ( $sectionIds ) {
3379 return !in_array( $entry[2], $sectionIds, true );
3382 // Make "on resolution" callbacks owned by this savepoint to perceive a rollback
3383 foreach ( $this->trxEndCallbacks
as $key => $entry ) {
3384 if ( in_array( $entry[2], $sectionIds, true ) ) {
3385 $callback = $entry[0];
3386 $this->trxEndCallbacks
[$key][0] = function () use ( $callback ) {
3387 return $callback( self
::TRIGGER_ROLLBACK
, $this );
3393 final public function setTransactionListener( $name, callable
$callback = null ) {
3395 $this->trxRecurringCallbacks
[$name] = $callback;
3397 unset( $this->trxRecurringCallbacks
[$name] );
3402 * Whether to disable running of post-COMMIT/ROLLBACK callbacks
3404 * This method should not be used outside of Database/LoadBalancer
3406 * @param bool $suppress
3409 final public function setTrxEndCallbackSuppression( $suppress ) {
3410 $this->trxEndCallbacksSuppressed
= $suppress;
3414 * Actually consume and run any "on transaction idle/resolution" callbacks.
3416 * This method should not be used outside of Database/LoadBalancer
3418 * @param int $trigger IDatabase::TRIGGER_* constant
3419 * @return int Number of callbacks attempted
3423 public function runOnTransactionIdleCallbacks( $trigger ) {
3424 if ( $this->trxLevel
) { // sanity
3425 throw new DBUnexpectedError( $this, __METHOD__
. ': a transaction is still open.' );
3428 if ( $this->trxEndCallbacksSuppressed
) {
3433 $autoTrx = $this->getFlag( self
::DBO_TRX
); // automatic begin() enabled?
3434 /** @var Exception $e */
3435 $e = null; // first exception
3436 do { // callbacks may add callbacks :)
3437 $callbacks = array_merge(
3438 $this->trxIdleCallbacks
,
3439 $this->trxEndCallbacks
// include "transaction resolution" callbacks
3441 $this->trxIdleCallbacks
= []; // consumed (and recursion guard)
3442 $this->trxEndCallbacks
= []; // consumed (recursion guard)
3443 foreach ( $callbacks as $callback ) {
3445 list( $phpCallback ) = $callback;
3446 $this->clearFlag( self
::DBO_TRX
); // make each query its own transaction
3448 call_user_func( $phpCallback, $trigger, $this );
3449 } catch ( Exception
$ex ) {
3450 call_user_func( $this->errorLogger
, $ex );
3452 // Some callbacks may use startAtomic/endAtomic, so make sure
3453 // their transactions are ended so other callbacks don't fail
3454 if ( $this->trxLevel() ) {
3455 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
3459 $this->setFlag( self
::DBO_TRX
); // restore automatic begin()
3461 $this->clearFlag( self
::DBO_TRX
); // restore auto-commit
3465 } while ( count( $this->trxIdleCallbacks
) );
3467 if ( $e instanceof Exception
) {
3468 throw $e; // re-throw any first exception
3475 * Actually consume and run any "on transaction pre-commit" callbacks.
3477 * This method should not be used outside of Database/LoadBalancer
3480 * @return int Number of callbacks attempted
3483 public function runOnTransactionPreCommitCallbacks() {
3486 $e = null; // first exception
3487 do { // callbacks may add callbacks :)
3488 $callbacks = $this->trxPreCommitCallbacks
;
3489 $this->trxPreCommitCallbacks
= []; // consumed (and recursion guard)
3490 foreach ( $callbacks as $callback ) {
3493 list( $phpCallback ) = $callback;
3494 $phpCallback( $this );
3495 } catch ( Exception
$ex ) {
3496 $this->errorLogger( $ex );
3500 } while ( count( $this->trxPreCommitCallbacks
) );
3502 if ( $e instanceof Exception
) {
3503 throw $e; // re-throw any first exception
3510 * Actually run any "transaction listener" callbacks.
3512 * This method should not be used outside of Database/LoadBalancer
3514 * @param int $trigger IDatabase::TRIGGER_* constant
3518 public function runTransactionListenerCallbacks( $trigger ) {
3519 if ( $this->trxEndCallbacksSuppressed
) {
3523 /** @var Exception $e */
3524 $e = null; // first exception
3526 foreach ( $this->trxRecurringCallbacks
as $phpCallback ) {
3528 $phpCallback( $trigger, $this );
3529 } catch ( Exception
$ex ) {
3530 ( $this->errorLogger
)( $ex );
3535 if ( $e instanceof Exception
) {
3536 throw $e; // re-throw any first exception
3541 * Create a savepoint
3543 * This is used internally to implement atomic sections. It should not be
3547 * @param string $identifier Identifier for the savepoint
3548 * @param string $fname Calling function name
3550 protected function doSavepoint( $identifier, $fname ) {
3551 $this->query( 'SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3555 * Release a savepoint
3557 * This is used internally to implement atomic sections. It should not be
3561 * @param string $identifier Identifier for the savepoint
3562 * @param string $fname Calling function name
3564 protected function doReleaseSavepoint( $identifier, $fname ) {
3565 $this->query( 'RELEASE SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3569 * Rollback to a savepoint
3571 * This is used internally to implement atomic sections. It should not be
3575 * @param string $identifier Identifier for the savepoint
3576 * @param string $fname Calling function name
3578 protected function doRollbackToSavepoint( $identifier, $fname ) {
3579 $this->query( 'ROLLBACK TO SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3583 * @param string $fname
3586 private function nextSavepointId( $fname ) {
3587 $savepointId = self
::$SAVEPOINT_PREFIX . ++
$this->trxAtomicCounter
;
3588 if ( strlen( $savepointId ) > 30 ) {
3589 // 30 == Oracle's identifier length limit (pre 12c)
3590 // With a 22 character prefix, that puts the highest number at 99999999.
3591 throw new DBUnexpectedError(
3593 'There have been an excessively large number of atomic sections in a transaction'
3594 . " started by $this->trxFname (at $fname)"
3598 return $savepointId;
3601 final public function startAtomic(
3602 $fname = __METHOD__
, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3604 $savepointId = $cancelable === self
::ATOMIC_CANCELABLE ? self
::$NOT_APPLICABLE : null;
3606 if ( !$this->trxLevel
) {
3607 $this->begin( $fname, self
::TRANSACTION_INTERNAL
); // sets trxAutomatic
3608 // If DBO_TRX is set, a series of startAtomic/endAtomic pairs will result
3609 // in all changes being in one transaction to keep requests transactional.
3610 if ( $this->getFlag( self
::DBO_TRX
) ) {
3611 // Since writes could happen in between the topmost atomic sections as part
3612 // of the transaction, those sections will need savepoints.
3613 $savepointId = $this->nextSavepointId( $fname );
3614 $this->doSavepoint( $savepointId, $fname );
3616 $this->trxAutomaticAtomic
= true;
3618 } elseif ( $cancelable === self
::ATOMIC_CANCELABLE
) {
3619 $savepointId = $this->nextSavepointId( $fname );
3620 $this->doSavepoint( $savepointId, $fname );
3623 $sectionId = new AtomicSectionIdentifier
;
3624 $this->trxAtomicLevels
[] = [ $fname, $sectionId, $savepointId ];
3629 final public function endAtomic( $fname = __METHOD__
) {
3630 if ( !$this->trxLevel ||
!$this->trxAtomicLevels
) {
3631 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)." );
3634 // Check if the current section matches $fname
3635 $pos = count( $this->trxAtomicLevels
) - 1;
3636 list( $savedFname, $sectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3638 if ( $savedFname !== $fname ) {
3639 throw new DBUnexpectedError(
3641 "Invalid atomic section ended (got $fname but expected $savedFname)."
3645 // Remove the last section (no need to re-index the array)
3646 array_pop( $this->trxAtomicLevels
);
3648 if ( !$this->trxAtomicLevels
&& $this->trxAutomaticAtomic
) {
3649 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3650 } elseif ( $savepointId !== null && $savepointId !== self
::$NOT_APPLICABLE ) {
3651 $this->doReleaseSavepoint( $savepointId, $fname );
3654 // Hoist callback ownership for callbacks in the section that just ended;
3655 // all callbacks should have an owner that is present in trxAtomicLevels.
3656 $currentSectionId = $this->currentAtomicSectionId();
3657 if ( $currentSectionId ) {
3658 $this->reassignCallbacksForSection( $sectionId, $currentSectionId );
3662 final public function cancelAtomic(
3663 $fname = __METHOD__
, AtomicSectionIdentifier
$sectionId = null
3665 if ( !$this->trxLevel ||
!$this->trxAtomicLevels
) {
3666 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)." );
3669 if ( $sectionId !== null ) {
3670 // Find the (last) section with the given $sectionId
3672 foreach ( $this->trxAtomicLevels
as $i => list( $asFname, $asId, $spId ) ) {
3673 if ( $asId === $sectionId ) {
3678 throw new DBUnexpectedError( "Atomic section not found (for $fname)" );
3680 // Remove all descendant sections and re-index the array
3682 $len = count( $this->trxAtomicLevels
);
3683 for ( $i = $pos +
1; $i < $len; ++
$i ) {
3684 $excisedIds[] = $this->trxAtomicLevels
[$i][1];
3686 $this->trxAtomicLevels
= array_slice( $this->trxAtomicLevels
, 0, $pos +
1 );
3687 $this->modifyCallbacksForCancel( $excisedIds );
3690 // Check if the current section matches $fname
3691 $pos = count( $this->trxAtomicLevels
) - 1;
3692 list( $savedFname, $savedSectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3694 if ( $savedFname !== $fname ) {
3695 throw new DBUnexpectedError(
3697 "Invalid atomic section ended (got $fname but expected $savedFname)."
3701 // Remove the last section (no need to re-index the array)
3702 array_pop( $this->trxAtomicLevels
);
3703 $this->modifyCallbacksForCancel( [ $savedSectionId ] );
3705 if ( $savepointId !== null ) {
3706 // Rollback the transaction to the state just before this atomic section
3707 if ( $savepointId === self
::$NOT_APPLICABLE ) {
3708 $this->rollback( $fname, self
::FLUSHING_INTERNAL
);
3710 $this->doRollbackToSavepoint( $savepointId, $fname );
3711 $this->trxStatus
= self
::STATUS_TRX_OK
; // no exception; recovered
3712 $this->trxStatusIgnoredCause
= null;
3714 } elseif ( $this->trxStatus
> self
::STATUS_TRX_ERROR
) {
3715 // Put the transaction into an error state if it's not already in one
3716 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
3717 $this->trxStatusCause
= new DBUnexpectedError(
3719 "Uncancelable atomic section canceled (got $fname)."
3723 $this->affectedRowCount
= 0; // for the sake of consistency
3726 final public function doAtomicSection(
3727 $fname, callable
$callback, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3729 $sectionId = $this->startAtomic( $fname, $cancelable );
3731 $res = $callback( $this, $fname );
3732 } catch ( Exception
$e ) {
3733 $this->cancelAtomic( $fname, $sectionId );
3737 $this->endAtomic( $fname );
3742 final public function begin( $fname = __METHOD__
, $mode = self
::TRANSACTION_EXPLICIT
) {
3743 static $modes = [ self
::TRANSACTION_EXPLICIT
, self
::TRANSACTION_INTERNAL
];
3744 if ( !in_array( $mode, $modes, true ) ) {
3745 throw new DBUnexpectedError( $this, "$fname: invalid mode parameter '$mode'." );
3748 // Protect against mismatched atomic section, transaction nesting, and snapshot loss
3749 if ( $this->trxLevel
) {
3750 if ( $this->trxAtomicLevels
) {
3751 $levels = $this->flatAtomicSectionList();
3752 $msg = "$fname: Got explicit BEGIN while atomic section(s) $levels are open.";
3753 throw new DBUnexpectedError( $this, $msg );
3754 } elseif ( !$this->trxAutomatic
) {
3755 $msg = "$fname: Explicit transaction already active (from {$this->trxFname}).";
3756 throw new DBUnexpectedError( $this, $msg );
3758 $msg = "$fname: Implicit transaction already active (from {$this->trxFname}).";
3759 throw new DBUnexpectedError( $this, $msg );
3761 } elseif ( $this->getFlag( self
::DBO_TRX
) && $mode !== self
::TRANSACTION_INTERNAL
) {
3762 $msg = "$fname: Implicit transaction expected (DBO_TRX set).";
3763 throw new DBUnexpectedError( $this, $msg );
3766 // Avoid fatals if close() was called
3767 $this->assertOpen();
3769 $this->doBegin( $fname );
3770 $this->trxStatus
= self
::STATUS_TRX_OK
;
3771 $this->trxStatusIgnoredCause
= null;
3772 $this->trxAtomicCounter
= 0;
3773 $this->trxTimestamp
= microtime( true );
3774 $this->trxFname
= $fname;
3775 $this->trxDoneWrites
= false;
3776 $this->trxAutomaticAtomic
= false;
3777 $this->trxAtomicLevels
= [];
3778 $this->trxShortId
= sprintf( '%06x', mt_rand( 0, 0xffffff ) );
3779 $this->trxWriteDuration
= 0.0;
3780 $this->trxWriteQueryCount
= 0;
3781 $this->trxWriteAffectedRows
= 0;
3782 $this->trxWriteAdjDuration
= 0.0;
3783 $this->trxWriteAdjQueryCount
= 0;
3784 $this->trxWriteCallers
= [];
3785 // First SELECT after BEGIN will establish the snapshot in REPEATABLE-READ.
3786 // Get an estimate of the replication lag before any such queries.
3787 $this->trxReplicaLag
= null; // clear cached value first
3788 $this->trxReplicaLag
= $this->getApproximateLagStatus()['lag'];
3789 // T147697: make explicitTrxActive() return true until begin() finishes. This way, no
3790 // caller will think its OK to muck around with the transaction just because startAtomic()
3791 // has not yet completed (e.g. setting trxAtomicLevels).
3792 $this->trxAutomatic
= ( $mode === self
::TRANSACTION_INTERNAL
);
3796 * Issues the BEGIN command to the database server.
3798 * @see Database::begin()
3799 * @param string $fname
3801 protected function doBegin( $fname ) {
3802 $this->query( 'BEGIN', $fname );
3803 $this->trxLevel
= 1;
3806 final public function commit( $fname = __METHOD__
, $flush = self
::FLUSHING_ONE
) {
3807 static $modes = [ self
::FLUSHING_ONE
, self
::FLUSHING_ALL_PEERS
, self
::FLUSHING_INTERNAL
];
3808 if ( !in_array( $flush, $modes, true ) ) {
3809 throw new DBUnexpectedError( $this, "$fname: invalid flush parameter '$flush'." );
3812 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3813 // There are still atomic sections open; this cannot be ignored
3814 $levels = $this->flatAtomicSectionList();
3815 throw new DBUnexpectedError(
3817 "$fname: Got COMMIT while atomic sections $levels are still open."
3821 if ( $flush === self
::FLUSHING_INTERNAL ||
$flush === self
::FLUSHING_ALL_PEERS
) {
3822 if ( !$this->trxLevel
) {
3823 return; // nothing to do
3824 } elseif ( !$this->trxAutomatic
) {
3825 throw new DBUnexpectedError(
3827 "$fname: Flushing an explicit transaction, getting out of sync."
3831 if ( !$this->trxLevel
) {
3832 $this->queryLogger
->error(
3833 "$fname: No transaction to commit, something got out of sync." );
3834 return; // nothing to do
3835 } elseif ( $this->trxAutomatic
) {
3836 throw new DBUnexpectedError(
3838 "$fname: Expected mass commit of all peer transactions (DBO_TRX set)."
3843 // Avoid fatals if close() was called
3844 $this->assertOpen();
3846 $this->runOnTransactionPreCommitCallbacks();
3847 $writeTime = $this->pendingWriteQueryDuration( self
::ESTIMATE_DB_APPLY
);
3848 $this->doCommit( $fname );
3849 $this->trxStatus
= self
::STATUS_TRX_NONE
;
3850 if ( $this->trxDoneWrites
) {
3851 $this->lastWriteTime
= microtime( true );
3852 $this->trxProfiler
->transactionWritingOut(
3857 $this->trxWriteAffectedRows
3861 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
3862 if ( $flush !== self
::FLUSHING_ALL_PEERS
) {
3863 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_COMMIT
);
3864 $this->runTransactionListenerCallbacks( self
::TRIGGER_COMMIT
);
3869 * Issues the COMMIT command to the database server.
3871 * @see Database::commit()
3872 * @param string $fname
3874 protected function doCommit( $fname ) {
3875 if ( $this->trxLevel
) {
3876 $this->query( 'COMMIT', $fname );
3877 $this->trxLevel
= 0;
3881 final public function rollback( $fname = __METHOD__
, $flush = '' ) {
3882 $trxActive = $this->trxLevel
;
3884 if ( $flush !== self
::FLUSHING_INTERNAL
&& $flush !== self
::FLUSHING_ALL_PEERS
) {
3885 if ( $this->getFlag( self
::DBO_TRX
) ) {
3886 throw new DBUnexpectedError(
3888 "$fname: Expected mass rollback of all peer transactions (DBO_TRX set)."
3894 // Avoid fatals if close() was called
3895 $this->assertOpen();
3897 $this->doRollback( $fname );
3898 $this->trxStatus
= self
::STATUS_TRX_NONE
;
3899 $this->trxAtomicLevels
= [];
3900 if ( $this->trxDoneWrites
) {
3901 $this->trxProfiler
->transactionWritingOut(
3909 // Clear any commit-dependant callbacks. They might even be present
3910 // only due to transaction rounds, with no SQL transaction being active
3911 $this->trxIdleCallbacks
= [];
3912 $this->trxPreCommitCallbacks
= [];
3914 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
3915 if ( $trxActive && $flush !== self
::FLUSHING_ALL_PEERS
) {
3917 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
3918 } catch ( Exception
$e ) {
3919 // already logged; finish and let LoadBalancer move on during mass-rollback
3922 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
3923 } catch ( Exception
$e ) {
3924 // already logged; let LoadBalancer move on during mass-rollback
3927 $this->affectedRowCount
= 0; // for the sake of consistency
3932 * Issues the ROLLBACK command to the database server.
3934 * @see Database::rollback()
3935 * @param string $fname
3937 protected function doRollback( $fname ) {
3938 if ( $this->trxLevel
) {
3939 # Disconnects cause rollback anyway, so ignore those errors
3940 $ignoreErrors = true;
3941 $this->query( 'ROLLBACK', $fname, $ignoreErrors );
3942 $this->trxLevel
= 0;
3946 public function flushSnapshot( $fname = __METHOD__
) {
3947 if ( $this->writesOrCallbacksPending() ||
$this->explicitTrxActive() ) {
3948 // This only flushes transactions to clear snapshots, not to write data
3949 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
3950 throw new DBUnexpectedError(
3952 "$fname: Cannot flush snapshot because writes are pending ($fnames)."
3956 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3959 public function explicitTrxActive() {
3960 return $this->trxLevel
&& ( $this->trxAtomicLevels ||
!$this->trxAutomatic
);
3963 public function duplicateTableStructure(
3964 $oldName, $newName, $temporary = false, $fname = __METHOD__
3966 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
3969 public function listTables( $prefix = null, $fname = __METHOD__
) {
3970 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
3973 public function listViews( $prefix = null, $fname = __METHOD__
) {
3974 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
3977 public function timestamp( $ts = 0 ) {
3978 $t = new ConvertibleTimestamp( $ts );
3979 // Let errors bubble up to avoid putting garbage in the DB
3980 return $t->getTimestamp( TS_MW
);
3983 public function timestampOrNull( $ts = null ) {
3984 if ( is_null( $ts ) ) {
3987 return $this->timestamp( $ts );
3991 public function affectedRows() {
3992 return ( $this->affectedRowCount
=== null )
3993 ?
$this->fetchAffectedRowCount() // default to driver value
3994 : $this->affectedRowCount
;
3998 * @return int Number of retrieved rows according to the driver
4000 abstract protected function fetchAffectedRowCount();
4003 * Take the result from a query, and wrap it in a ResultWrapper if
4004 * necessary. Boolean values are passed through as is, to indicate success
4005 * of write queries or failure.
4007 * Once upon a time, Database::query() returned a bare MySQL result
4008 * resource, and it was necessary to call this function to convert it to
4009 * a wrapper. Nowadays, raw database objects are never exposed to external
4010 * callers, so this is unnecessary in external code.
4012 * @param bool|ResultWrapper|resource|object $result
4013 * @return bool|ResultWrapper
4015 protected function resultObject( $result ) {
4018 } elseif ( $result instanceof ResultWrapper
) {
4020 } elseif ( $result === true ) {
4021 // Successful write query
4024 return new ResultWrapper( $this, $result );
4028 public function ping( &$rtt = null ) {
4029 // Avoid hitting the server if it was hit recently
4030 if ( $this->isOpen() && ( microtime( true ) - $this->lastPing
) < self
::PING_TTL
) {
4031 if ( !func_num_args() ||
$this->rttEstimate
> 0 ) {
4032 $rtt = $this->rttEstimate
;
4033 return true; // don't care about $rtt
4037 // This will reconnect if possible or return false if not
4038 $this->clearFlag( self
::DBO_TRX
, self
::REMEMBER_PRIOR
);
4039 $ok = ( $this->query( self
::PING_QUERY
, __METHOD__
, true ) !== false );
4040 $this->restoreFlags( self
::RESTORE_PRIOR
);
4043 $rtt = $this->rttEstimate
;
4050 * Close any existing (dead) database connection and open a new connection
4052 * @param string $fname
4053 * @return bool True if new connection is opened successfully, false if error
4055 protected function replaceLostConnection( $fname ) {
4056 $this->closeConnection();
4057 $this->opened
= false;
4058 $this->conn
= false;
4060 $this->open( $this->server
, $this->user
, $this->password
, $this->dbName
);
4061 $this->lastPing
= microtime( true );
4064 $this->connLogger
->warning(
4065 $fname . ': lost connection to {dbserver}; reconnected',
4067 'dbserver' => $this->getServer(),
4068 'trace' => ( new RuntimeException() )->getTraceAsString()
4071 } catch ( DBConnectionError
$e ) {
4074 $this->connLogger
->error(
4075 $fname . ': lost connection to {dbserver} permanently',
4076 [ 'dbserver' => $this->getServer() ]
4080 $this->handleSessionLoss();
4085 public function getSessionLagStatus() {
4086 return $this->getRecordedTransactionLagStatus() ?
: $this->getApproximateLagStatus();
4090 * Get the replica DB lag when the current transaction started
4092 * This is useful when transactions might use snapshot isolation
4093 * (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data
4094 * is this lag plus transaction duration. If they don't, it is still
4095 * safe to be pessimistic. This returns null if there is no transaction.
4097 * This returns null if the lag status for this transaction was not yet recorded.
4099 * @return array|null ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)
4102 final protected function getRecordedTransactionLagStatus() {
4103 return ( $this->trxLevel
&& $this->trxReplicaLag
!== null )
4104 ?
[ 'lag' => $this->trxReplicaLag
, 'since' => $this->trxTimestamp() ]
4109 * Get a replica DB lag estimate for this server
4111 * @return array ('lag': seconds or false on error, 'since': UNIX timestamp of estimate)
4114 protected function getApproximateLagStatus() {
4116 'lag' => $this->getLBInfo( 'replica' ) ?
$this->getLag() : 0,
4117 'since' => microtime( true )
4122 * Merge the result of getSessionLagStatus() for several DBs
4123 * using the most pessimistic values to estimate the lag of
4124 * any data derived from them in combination
4126 * This is information is useful for caching modules
4128 * @see WANObjectCache::set()
4129 * @see WANObjectCache::getWithSetCallback()
4131 * @param IDatabase $db1
4132 * @param IDatabase|null $db2 [optional]
4133 * @return array Map of values:
4134 * - lag: highest lag of any of the DBs or false on error (e.g. replication stopped)
4135 * - since: oldest UNIX timestamp of any of the DB lag estimates
4136 * - pending: whether any of the DBs have uncommitted changes
4140 public static function getCacheSetOptions( IDatabase
$db1, IDatabase
$db2 = null ) {
4141 $res = [ 'lag' => 0, 'since' => INF
, 'pending' => false ];
4142 foreach ( func_get_args() as $db ) {
4143 /** @var IDatabase $db */
4144 $status = $db->getSessionLagStatus();
4145 if ( $status['lag'] === false ) {
4146 $res['lag'] = false;
4147 } elseif ( $res['lag'] !== false ) {
4148 $res['lag'] = max( $res['lag'], $status['lag'] );
4150 $res['since'] = min( $res['since'], $status['since'] );
4151 $res['pending'] = $res['pending'] ?
: $db->writesPending();
4157 public function getLag() {
4161 public function maxListLen() {
4165 public function encodeBlob( $b ) {
4169 public function decodeBlob( $b ) {
4170 if ( $b instanceof Blob
) {
4176 public function setSessionOptions( array $options ) {
4179 public function sourceFile(
4181 callable
$lineCallback = null,
4182 callable
$resultCallback = null,
4184 callable
$inputCallback = null
4186 Wikimedia\
suppressWarnings();
4187 $fp = fopen( $filename, 'r' );
4188 Wikimedia\restoreWarnings
();
4190 if ( false === $fp ) {
4191 throw new RuntimeException( "Could not open \"{$filename}\".\n" );
4195 $fname = __METHOD__
. "( $filename )";
4199 $error = $this->sourceStream(
4200 $fp, $lineCallback, $resultCallback, $fname, $inputCallback );
4201 } catch ( Exception
$e ) {
4211 public function setSchemaVars( $vars ) {
4212 $this->schemaVars
= $vars;
4215 public function sourceStream(
4217 callable
$lineCallback = null,
4218 callable
$resultCallback = null,
4219 $fname = __METHOD__
,
4220 callable
$inputCallback = null
4222 $delimiterReset = new ScopedCallback(
4223 function ( $delimiter ) {
4224 $this->delimiter
= $delimiter;
4226 [ $this->delimiter
]
4230 while ( !feof( $fp ) ) {
4231 if ( $lineCallback ) {
4232 call_user_func( $lineCallback );
4235 $line = trim( fgets( $fp ) );
4237 if ( $line == '' ) {
4241 if ( '-' == $line[0] && '-' == $line[1] ) {
4249 $done = $this->streamStatementEnd( $cmd, $line );
4253 if ( $done ||
feof( $fp ) ) {
4254 $cmd = $this->replaceVars( $cmd );
4256 if ( $inputCallback ) {
4257 $callbackResult = $inputCallback( $cmd );
4259 if ( is_string( $callbackResult ) ||
!$callbackResult ) {
4260 $cmd = $callbackResult;
4265 $res = $this->query( $cmd, $fname );
4267 if ( $resultCallback ) {
4268 $resultCallback( $res, $this );
4271 if ( false === $res ) {
4272 $err = $this->lastError();
4274 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
4281 ScopedCallback
::consume( $delimiterReset );
4286 * Called by sourceStream() to check if we've reached a statement end
4288 * @param string &$sql SQL assembled so far
4289 * @param string &$newLine New line about to be added to $sql
4290 * @return bool Whether $newLine contains end of the statement
4292 public function streamStatementEnd( &$sql, &$newLine ) {
4293 if ( $this->delimiter
) {
4295 $newLine = preg_replace(
4296 '/' . preg_quote( $this->delimiter
, '/' ) . '$/', '', $newLine );
4297 if ( $newLine != $prev ) {
4306 * Database independent variable replacement. Replaces a set of variables
4307 * in an SQL statement with their contents as given by $this->getSchemaVars().
4309 * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables.
4311 * - '{$var}' should be used for text and is passed through the database's
4313 * - `{$var}` should be used for identifiers (e.g. table and database names).
4314 * It is passed through the database's addIdentifierQuotes method which
4315 * can be overridden if the database uses something other than backticks.
4316 * - / *_* / or / *$wgDBprefix* / passes the name that follows through the
4317 * database's tableName method.
4318 * - / *i* / passes the name that follows through the database's indexName method.
4319 * - In all other cases, / *$var* / is left unencoded. Except for table options,
4320 * its use should be avoided. In 1.24 and older, string encoding was applied.
4322 * @param string $ins SQL statement to replace variables in
4323 * @return string The new SQL statement with variables replaced
4325 protected function replaceVars( $ins ) {
4326 $vars = $this->getSchemaVars();
4327 return preg_replace_callback(
4329 /\* (\$wgDBprefix|[_i]) \*/ (\w*) | # 1-2. tableName, indexName
4330 \'\{\$ (\w+) }\' | # 3. addQuotes
4331 `\{\$ (\w+) }` | # 4. addIdentifierQuotes
4332 /\*\$ (\w+) \*/ # 5. leave unencoded
4334 function ( $m ) use ( $vars ) {
4335 // Note: Because of <https://bugs.php.net/bug.php?id=51881>,
4336 // check for both nonexistent keys *and* the empty string.
4337 if ( isset( $m[1] ) && $m[1] !== '' ) {
4338 if ( $m[1] === 'i' ) {
4339 return $this->indexName( $m[2] );
4341 return $this->tableName( $m[2] );
4343 } elseif ( isset( $m[3] ) && $m[3] !== '' && array_key_exists( $m[3], $vars ) ) {
4344 return $this->addQuotes( $vars[$m[3]] );
4345 } elseif ( isset( $m[4] ) && $m[4] !== '' && array_key_exists( $m[4], $vars ) ) {
4346 return $this->addIdentifierQuotes( $vars[$m[4]] );
4347 } elseif ( isset( $m[5] ) && $m[5] !== '' && array_key_exists( $m[5], $vars ) ) {
4348 return $vars[$m[5]];
4358 * Get schema variables. If none have been set via setSchemaVars(), then
4359 * use some defaults from the current object.
4363 protected function getSchemaVars() {
4364 if ( $this->schemaVars
) {
4365 return $this->schemaVars
;
4367 return $this->getDefaultSchemaVars();
4372 * Get schema variables to use if none have been set via setSchemaVars().
4374 * Override this in derived classes to provide variables for tables.sql
4375 * and SQL patch files.
4379 protected function getDefaultSchemaVars() {
4383 public function lockIsFree( $lockName, $method ) {
4384 // RDBMs methods for checking named locks may or may not count this thread itself.
4385 // In MySQL, IS_FREE_LOCK() returns 0 if the thread already has the lock. This is
4386 // the behavior choosen by the interface for this method.
4387 return !isset( $this->namedLocksHeld
[$lockName] );
4390 public function lock( $lockName, $method, $timeout = 5 ) {
4391 $this->namedLocksHeld
[$lockName] = 1;
4396 public function unlock( $lockName, $method ) {
4397 unset( $this->namedLocksHeld
[$lockName] );
4402 public function getScopedLockAndFlush( $lockKey, $fname, $timeout ) {
4403 if ( $this->writesOrCallbacksPending() ) {
4404 // This only flushes transactions to clear snapshots, not to write data
4405 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4406 throw new DBUnexpectedError(
4408 "$fname: Cannot flush pre-lock snapshot because writes are pending ($fnames)."
4412 if ( !$this->lock( $lockKey, $fname, $timeout ) ) {
4416 $unlocker = new ScopedCallback( function () use ( $lockKey, $fname ) {
4417 if ( $this->trxLevel() ) {
4418 // There is a good chance an exception was thrown, causing any early return
4419 // from the caller. Let any error handler get a chance to issue rollback().
4420 // If there isn't one, let the error bubble up and trigger server-side rollback.
4421 $this->onTransactionResolution(
4422 function () use ( $lockKey, $fname ) {
4423 $this->unlock( $lockKey, $fname );
4428 $this->unlock( $lockKey, $fname );
4432 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4437 public function namedLocksEnqueue() {
4441 public function tableLocksHaveTransactionScope() {
4445 final public function lockTables( array $read, array $write, $method ) {
4446 if ( $this->writesOrCallbacksPending() ) {
4447 throw new DBUnexpectedError( $this, "Transaction writes or callbacks still pending." );
4450 if ( $this->tableLocksHaveTransactionScope() ) {
4451 $this->startAtomic( $method );
4454 return $this->doLockTables( $read, $write, $method );
4458 * Helper function for lockTables() that handles the actual table locking
4460 * @param array $read Array of tables to lock for read access
4461 * @param array $write Array of tables to lock for write access
4462 * @param string $method Name of caller
4465 protected function doLockTables( array $read, array $write, $method ) {
4469 final public function unlockTables( $method ) {
4470 if ( $this->tableLocksHaveTransactionScope() ) {
4471 $this->endAtomic( $method );
4473 return true; // locks released on COMMIT/ROLLBACK
4476 return $this->doUnlockTables( $method );
4480 * Helper function for unlockTables() that handles the actual table unlocking
4482 * @param string $method Name of caller
4485 protected function doUnlockTables( $method ) {
4491 * @param string $tableName
4492 * @param string $fName
4493 * @return bool|ResultWrapper
4496 public function dropTable( $tableName, $fName = __METHOD__
) {
4497 if ( !$this->tableExists( $tableName, $fName ) ) {
4500 $sql = "DROP TABLE " . $this->tableName( $tableName ) . " CASCADE";
4502 return $this->query( $sql, $fName );
4505 public function getInfinity() {
4509 public function encodeExpiry( $expiry ) {
4510 return ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() )
4511 ?
$this->getInfinity()
4512 : $this->timestamp( $expiry );
4515 public function decodeExpiry( $expiry, $format = TS_MW
) {
4516 if ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() ) {
4520 return ConvertibleTimestamp
::convert( $format, $expiry );
4523 public function setBigSelects( $value = true ) {
4527 public function isReadOnly() {
4528 return ( $this->getReadOnlyReason() !== false );
4532 * @return string|bool Reason this DB is read-only or false if it is not
4534 protected function getReadOnlyReason() {
4535 $reason = $this->getLBInfo( 'readOnlyReason' );
4537 return is_string( $reason ) ?
$reason : false;
4540 public function setTableAliases( array $aliases ) {
4541 $this->tableAliases
= $aliases;
4544 public function setIndexAliases( array $aliases ) {
4545 $this->indexAliases
= $aliases;
4549 * Get the underlying binding connection handle
4551 * Makes sure the connection resource is set (disconnects and ping() failure can unset it).
4552 * This catches broken callers than catch and ignore disconnection exceptions.
4553 * Unlike checking isOpen(), this is safe to call inside of open().
4556 * @throws DBUnexpectedError
4559 protected function getBindingHandle() {
4560 if ( !$this->conn
) {
4561 throw new DBUnexpectedError(
4563 'DB connection was already closed or the connection dropped.'
4574 public function __toString() {
4575 return (string)$this->conn
;
4579 * Make sure that copies do not share the same client binding handle
4580 * @throws DBConnectionError
4582 public function __clone() {
4583 $this->connLogger
->warning(
4584 "Cloning " . static::class . " is not recomended; forking connection:\n" .
4585 ( new RuntimeException() )->getTraceAsString()
4588 if ( $this->isOpen() ) {
4589 // Open a new connection resource without messing with the old one
4590 $this->opened
= false;
4591 $this->conn
= false;
4592 $this->trxEndCallbacks
= []; // don't copy
4593 $this->handleSessionLoss(); // no trx or locks anymore
4594 $this->open( $this->server
, $this->user
, $this->password
, $this->dbName
);
4595 $this->lastPing
= microtime( true );
4600 * Called by serialize. Throw an exception when DB connection is serialized.
4601 * This causes problems on some database engines because the connection is
4602 * not restored on unserialize.
4604 public function __sleep() {
4605 throw new RuntimeException( 'Database serialization may cause problems, since ' .
4606 'the connection is not restored on wakeup.' );
4610 * Run a few simple sanity checks and close dangling connections
4612 public function __destruct() {
4613 if ( $this->trxLevel
&& $this->trxDoneWrites
) {
4614 trigger_error( "Uncommitted DB writes (transaction from {$this->trxFname})." );
4617 $danglingWriters = $this->pendingWriteAndCallbackCallers();
4618 if ( $danglingWriters ) {
4619 $fnames = implode( ', ', $danglingWriters );
4620 trigger_error( "DB transaction writes or callbacks still pending ($fnames)." );
4623 if ( $this->conn
) {
4624 // Avoid connection leaks for sanity. Normally, resources close at script completion.
4625 // The connection might already be closed in zend/hhvm by now, so suppress warnings.
4626 Wikimedia\
suppressWarnings();
4627 $this->closeConnection();
4628 Wikimedia\restoreWarnings
();
4629 $this->conn
= false;
4630 $this->opened
= false;
4636 * @deprecated since 1.28
4638 class_alias( Database
::class, 'DatabaseBase' );
4641 * @deprecated since 1.29
4643 class_alias( Database
::class, 'Database' );