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;
105 /** @var resource|null Database connection */
106 protected $conn = null;
108 protected $opened = false;
110 /** @var array[] List of (callable, method name) */
111 protected $trxIdleCallbacks = [];
112 /** @var array[] List of (callable, method name) */
113 protected $trxPreCommitCallbacks = [];
114 /** @var array[] List of (callable, method name) */
115 protected $trxEndCallbacks = [];
116 /** @var callable[] Map of (name => callable) */
117 protected $trxRecurringCallbacks = [];
118 /** @var bool Whether to suppress triggering of transaction end callbacks */
119 protected $trxEndCallbacksSuppressed = false;
122 protected $tablePrefix = '';
124 protected $schema = '';
128 protected $lbInfo = [];
129 /** @var array|bool */
130 protected $schemaVars = false;
132 protected $sessionVars = [];
133 /** @var array|null */
134 protected $preparedArgs;
135 /** @var string|bool|null Stashed value of html_errors INI setting */
136 protected $htmlErrors;
138 protected $delimiter = ';';
139 /** @var DatabaseDomain */
140 protected $currentDomain;
141 /** @var integer|null Rows affected by the last query to query() or its CRUD wrappers */
142 protected $affectedRowCount;
145 * Either 1 if a transaction is active or 0 otherwise.
146 * The other Trx fields may not be meaningfull if this is 0.
150 protected $trxLevel = 0;
152 * Either a short hexidecimal string if a transaction is active or ""
155 * @see Database::trxLevel
157 protected $trxShortId = '';
159 * The UNIX time that the transaction started. Callers can assume that if
160 * snapshot isolation is used, then the data is *at least* up to date to that
161 * point (possibly more up-to-date since the first SELECT defines the snapshot).
164 * @see Database::trxLevel
166 private $trxTimestamp = null;
167 /** @var float Lag estimate at the time of BEGIN */
168 private $trxReplicaLag = null;
170 * Remembers the function name given for starting the most recent transaction via begin().
171 * Used to provide additional context for error reporting.
174 * @see Database::trxLevel
176 private $trxFname = null;
178 * Record if possible write queries were done in the last transaction started
181 * @see Database::trxLevel
183 private $trxDoneWrites = false;
185 * Record if the current transaction was started implicitly due to DBO_TRX being set.
188 * @see Database::trxLevel
190 private $trxAutomatic = false;
192 * Counter for atomic savepoint identifiers. Reset when a new transaction begins.
196 private $trxAtomicCounter = 0;
198 * Array of levels of atomicity within transactions
202 private $trxAtomicLevels = [];
204 * Record if the current transaction was started implicitly by Database::startAtomic
208 private $trxAutomaticAtomic = false;
210 * Track the write query callers of the current transaction
214 private $trxWriteCallers = [];
216 * @var float Seconds spent in write queries for the current transaction
218 private $trxWriteDuration = 0.0;
220 * @var int Number of write queries for the current transaction
222 private $trxWriteQueryCount = 0;
224 * @var int Number of rows affected by write queries for the current transaction
226 private $trxWriteAffectedRows = 0;
228 * @var float Like trxWriteQueryCount but excludes lock-bound, easy to replicate, queries
230 private $trxWriteAdjDuration = 0.0;
232 * @var int Number of write queries counted in trxWriteAdjDuration
234 private $trxWriteAdjQueryCount = 0;
236 * @var float RTT time estimate
238 private $rttEstimate = 0.0;
240 /** @var array Map of (name => 1) for locks obtained via lock() */
241 private $namedLocksHeld = [];
242 /** @var array Map of (table name => 1) for TEMPORARY tables */
243 protected $sessionTempTables = [];
245 /** @var IDatabase|null Lazy handle to the master DB this server replicates from */
246 private $lazyMasterHandle;
248 /** @var float UNIX timestamp */
249 protected $lastPing = 0.0;
251 /** @var int[] Prior flags member variable values */
252 private $priorFlags = [];
254 /** @var object|string Class name or object With profileIn/profileOut methods */
256 /** @var TransactionProfiler */
257 protected $trxProfiler;
260 protected $nonNativeInsertSelectBatchSize = 10000;
263 * @note: exceptions for missing libraries/drivers should be thrown in initConnection()
264 * @param array $params Parameters passed from Database::factory()
266 protected function __construct( array $params ) {
267 foreach ( [ 'host', 'user', 'password', 'dbname' ] as $name ) {
268 $this->connectionParams
[$name] = $params[$name];
271 $this->schema
= $params['schema'];
272 $this->tablePrefix
= $params['tablePrefix'];
274 $this->cliMode
= $params['cliMode'];
275 // Agent name is added to SQL queries in a comment, so make sure it can't break out
276 $this->agent
= str_replace( '/', '-', $params['agent'] );
278 $this->flags
= $params['flags'];
279 if ( $this->flags
& self
::DBO_DEFAULT
) {
280 if ( $this->cliMode
) {
281 $this->flags
&= ~self
::DBO_TRX
;
283 $this->flags |
= self
::DBO_TRX
;
286 // Disregard deprecated DBO_IGNORE flag (T189999)
287 $this->flags
&= ~self
::DBO_IGNORE
;
289 $this->sessionVars
= $params['variables'];
291 $this->srvCache
= isset( $params['srvCache'] )
292 ?
$params['srvCache']
293 : new HashBagOStuff();
295 $this->profiler
= $params['profiler'];
296 $this->trxProfiler
= $params['trxProfiler'];
297 $this->connLogger
= $params['connLogger'];
298 $this->queryLogger
= $params['queryLogger'];
299 $this->errorLogger
= $params['errorLogger'];
301 if ( isset( $params['nonNativeInsertSelectBatchSize'] ) ) {
302 $this->nonNativeInsertSelectBatchSize
= $params['nonNativeInsertSelectBatchSize'];
305 // Set initial dummy domain until open() sets the final DB/prefix
306 $this->currentDomain
= DatabaseDomain
::newUnspecified();
310 * Initialize the connection to the database over the wire (or to local files)
312 * @throws LogicException
313 * @throws InvalidArgumentException
314 * @throws DBConnectionError
317 final public function initConnection() {
318 if ( $this->isOpen() ) {
319 throw new LogicException( __METHOD__
. ': already connected.' );
321 // Establish the connection
322 $this->doInitConnection();
323 // Set the domain object after open() sets the relevant fields
324 if ( $this->dbName
!= '' ) {
325 // Domains with server scope but a table prefix are not used by IDatabase classes
326 $this->currentDomain
= new DatabaseDomain( $this->dbName
, null, $this->tablePrefix
);
331 * Actually connect to the database over the wire (or to local files)
333 * @throws InvalidArgumentException
334 * @throws DBConnectionError
337 protected function doInitConnection() {
338 if ( strlen( $this->connectionParams
['user'] ) ) {
340 $this->connectionParams
['host'],
341 $this->connectionParams
['user'],
342 $this->connectionParams
['password'],
343 $this->connectionParams
['dbname']
346 throw new InvalidArgumentException( "No database user provided." );
351 * Construct a Database subclass instance given a database type and parameters
353 * This also connects to the database immediately upon object construction
355 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
356 * @param array $p Parameter map with keys:
357 * - host : The hostname of the DB server
358 * - user : The name of the database user the client operates under
359 * - password : The password for the database user
360 * - dbname : The name of the database to use where queries do not specify one.
361 * The database must exist or an error might be thrown. Setting this to the empty string
362 * will avoid any such errors and make the handle have no implicit database scope. This is
363 * useful for queries like SHOW STATUS, CREATE DATABASE, or DROP DATABASE. Note that a
364 * "database" in Postgres is rougly equivalent to an entire MySQL server. This the domain
365 * in which user names and such are defined, e.g. users are database-specific in Postgres.
366 * - schema : The database schema to use (if supported). A "schema" in Postgres is roughly
367 * equivalent to a "database" in MySQL. Note that MySQL and SQLite do not use schemas.
368 * - tablePrefix : Optional table prefix that is implicitly added on to all table names
369 * recognized in queries. This can be used in place of schemas for handle site farms.
370 * - flags : Optional bitfield of DBO_* constants that define connection, protocol,
371 * buffering, and transaction behavior. It is STRONGLY adviced to leave the DBO_DEFAULT
372 * flag in place UNLESS this this database simply acts as a key/value store.
373 * - driver: Optional name of a specific DB client driver. For MySQL, there is only the
374 * 'mysqli' driver; the old one 'mysql' has been removed.
375 * - variables: Optional map of session variables to set after connecting. This can be
376 * used to adjust lock timeouts or encoding modes and the like.
377 * - connLogger: Optional PSR-3 logger interface instance.
378 * - queryLogger: Optional PSR-3 logger interface instance.
379 * - profiler: Optional class name or object with profileIn()/profileOut() methods.
380 * These will be called in query(), using a simplified version of the SQL that also
381 * includes the agent as a SQL comment.
382 * - trxProfiler: Optional TransactionProfiler instance.
383 * - errorLogger: Optional callback that takes an Exception and logs it.
384 * - cliMode: Whether to consider the execution context that of a CLI script.
385 * - agent: Optional name used to identify the end-user in query profiling/logging.
386 * - srvCache: Optional BagOStuff instance to an APC-style cache.
387 * - nonNativeInsertSelectBatchSize: Optional batch size for non-native INSERT SELECT emulation.
388 * @param int $connect One of the class constants (NEW_CONNECTED, NEW_UNCONNECTED) [optional]
389 * @return Database|null If the database driver or extension cannot be found
390 * @throws InvalidArgumentException If the database driver or extension cannot be found
393 final public static function factory( $dbType, $p = [], $connect = self
::NEW_CONNECTED
) {
394 $class = self
::getClass( $dbType, isset( $p['driver'] ) ?
$p['driver'] : null );
396 if ( class_exists( $class ) && is_subclass_of( $class, IDatabase
::class ) ) {
397 // Resolve some defaults for b/c
398 $p['host'] = isset( $p['host'] ) ?
$p['host'] : false;
399 $p['user'] = isset( $p['user'] ) ?
$p['user'] : false;
400 $p['password'] = isset( $p['password'] ) ?
$p['password'] : false;
401 $p['dbname'] = isset( $p['dbname'] ) ?
$p['dbname'] : false;
402 $p['flags'] = isset( $p['flags'] ) ?
$p['flags'] : 0;
403 $p['variables'] = isset( $p['variables'] ) ?
$p['variables'] : [];
404 $p['tablePrefix'] = isset( $p['tablePrefix'] ) ?
$p['tablePrefix'] : '';
405 $p['schema'] = isset( $p['schema'] ) ?
$p['schema'] : '';
406 $p['cliMode'] = isset( $p['cliMode'] )
408 : ( PHP_SAPI
=== 'cli' || PHP_SAPI
=== 'phpdbg' );
409 $p['agent'] = isset( $p['agent'] ) ?
$p['agent'] : '';
410 if ( !isset( $p['connLogger'] ) ) {
411 $p['connLogger'] = new NullLogger();
413 if ( !isset( $p['queryLogger'] ) ) {
414 $p['queryLogger'] = new NullLogger();
416 $p['profiler'] = isset( $p['profiler'] ) ?
$p['profiler'] : null;
417 if ( !isset( $p['trxProfiler'] ) ) {
418 $p['trxProfiler'] = new TransactionProfiler();
420 if ( !isset( $p['errorLogger'] ) ) {
421 $p['errorLogger'] = function ( Exception
$e ) {
422 trigger_error( get_class( $e ) . ': ' . $e->getMessage(), E_USER_WARNING
);
426 /** @var Database $conn */
427 $conn = new $class( $p );
428 if ( $connect == self
::NEW_CONNECTED
) {
429 $conn->initConnection();
439 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
440 * @param string|null $driver Optional name of a specific DB client driver
441 * @return array Map of (Database::ATTRIBUTE_* constant => value) for all such constants
442 * @throws InvalidArgumentException
445 final public static function attributesFromType( $dbType, $driver = null ) {
446 static $defaults = [ self
::ATTR_DB_LEVEL_LOCKING
=> false ];
448 $class = self
::getClass( $dbType, $driver );
450 return call_user_func( [ $class, 'getAttributes' ] ) +
$defaults;
454 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
455 * @param string|null $driver Optional name of a specific DB client driver
456 * @return string Database subclass name to use
457 * @throws InvalidArgumentException
459 private static function getClass( $dbType, $driver = null ) {
460 // For database types with built-in support, the below maps type to IDatabase
461 // implementations. For types with multipe driver implementations (PHP extensions),
462 // an array can be used, keyed by extension name. In case of an array, the
463 // optional 'driver' parameter can be used to force a specific driver. Otherwise,
464 // we auto-detect the first available driver. For types without built-in support,
465 // an class named "Database<Type>" us used, eg. DatabaseFoo for type 'foo'.
466 static $builtinTypes = [
467 'mssql' => DatabaseMssql
::class,
468 'mysql' => [ 'mysqli' => DatabaseMysqli
::class ],
469 'sqlite' => DatabaseSqlite
::class,
470 'postgres' => DatabasePostgres
::class,
473 $dbType = strtolower( $dbType );
476 if ( isset( $builtinTypes[$dbType] ) ) {
477 $possibleDrivers = $builtinTypes[$dbType];
478 if ( is_string( $possibleDrivers ) ) {
479 $class = $possibleDrivers;
481 if ( (string)$driver !== '' ) {
482 if ( !isset( $possibleDrivers[$driver] ) ) {
483 throw new InvalidArgumentException( __METHOD__
.
484 " type '$dbType' does not support driver '{$driver}'" );
486 $class = $possibleDrivers[$driver];
489 foreach ( $possibleDrivers as $posDriver => $possibleClass ) {
490 if ( extension_loaded( $posDriver ) ) {
491 $class = $possibleClass;
498 $class = 'Database' . ucfirst( $dbType );
501 if ( $class === false ) {
502 throw new InvalidArgumentException( __METHOD__
.
503 " no viable database extension found for type '$dbType'" );
510 * @return array Map of (Database::ATTRIBUTE_* constant => value
513 protected static function getAttributes() {
518 * Set the PSR-3 logger interface to use for query logging. (The logger
519 * interfaces for connection logging and error logging can be set with the
522 * @param LoggerInterface $logger
524 public function setLogger( LoggerInterface
$logger ) {
525 $this->queryLogger
= $logger;
528 public function getServerInfo() {
529 return $this->getServerVersion();
532 public function bufferResults( $buffer = null ) {
533 $res = !$this->getFlag( self
::DBO_NOBUFFER
);
534 if ( $buffer !== null ) {
536 ?
$this->clearFlag( self
::DBO_NOBUFFER
)
537 : $this->setFlag( self
::DBO_NOBUFFER
);
543 public function trxLevel() {
544 return $this->trxLevel
;
547 public function trxTimestamp() {
548 return $this->trxLevel ?
$this->trxTimestamp
: null;
551 public function tablePrefix( $prefix = null ) {
552 $old = $this->tablePrefix
;
553 if ( $prefix !== null ) {
554 $this->tablePrefix
= $prefix;
555 $this->currentDomain
= ( $this->dbName
!= '' )
556 ?
new DatabaseDomain( $this->dbName
, null, $this->tablePrefix
)
557 : DatabaseDomain
::newUnspecified();
563 public function dbSchema( $schema = null ) {
564 $old = $this->schema
;
565 if ( $schema !== null ) {
566 $this->schema
= $schema;
572 public function getLBInfo( $name = null ) {
573 if ( is_null( $name ) ) {
574 return $this->lbInfo
;
576 if ( array_key_exists( $name, $this->lbInfo
) ) {
577 return $this->lbInfo
[$name];
584 public function setLBInfo( $name, $value = null ) {
585 if ( is_null( $value ) ) {
586 $this->lbInfo
= $name;
588 $this->lbInfo
[$name] = $value;
592 public function setLazyMasterHandle( IDatabase
$conn ) {
593 $this->lazyMasterHandle
= $conn;
597 * @return IDatabase|null
598 * @see setLazyMasterHandle()
601 protected function getLazyMasterHandle() {
602 return $this->lazyMasterHandle
;
605 public function implicitGroupby() {
609 public function implicitOrderby() {
613 public function lastQuery() {
614 return $this->lastQuery
;
617 public function doneWrites() {
618 return (bool)$this->lastWriteTime
;
621 public function lastDoneWrites() {
622 return $this->lastWriteTime ?
: false;
625 public function writesPending() {
626 return $this->trxLevel
&& $this->trxDoneWrites
;
629 public function writesOrCallbacksPending() {
630 return $this->trxLevel
&& (
631 $this->trxDoneWrites ||
632 $this->trxIdleCallbacks ||
633 $this->trxPreCommitCallbacks ||
634 $this->trxEndCallbacks
639 * @return string|null
641 final protected function getTransactionRoundId() {
642 // If transaction round participation is enabled, see if one is active
643 if ( $this->getFlag( self
::DBO_TRX
) ) {
644 $id = $this->getLBInfo( 'trxRoundId' );
646 return is_string( $id ) ?
$id : null;
652 public function pendingWriteQueryDuration( $type = self
::ESTIMATE_TOTAL
) {
653 if ( !$this->trxLevel
) {
655 } elseif ( !$this->trxDoneWrites
) {
660 case self
::ESTIMATE_DB_APPLY
:
662 $rttAdjTotal = $this->trxWriteAdjQueryCount
* $rtt;
663 $applyTime = max( $this->trxWriteAdjDuration
- $rttAdjTotal, 0 );
664 // For omitted queries, make them count as something at least
665 $omitted = $this->trxWriteQueryCount
- $this->trxWriteAdjQueryCount
;
666 $applyTime +
= self
::TINY_WRITE_SEC
* $omitted;
669 default: // everything
670 return $this->trxWriteDuration
;
674 public function pendingWriteCallers() {
675 return $this->trxLevel ?
$this->trxWriteCallers
: [];
678 public function pendingWriteRowsAffected() {
679 return $this->trxWriteAffectedRows
;
683 * Get the list of method names that have pending write queries or callbacks
684 * for this transaction
688 protected function pendingWriteAndCallbackCallers() {
689 if ( !$this->trxLevel
) {
693 $fnames = $this->trxWriteCallers
;
695 $this->trxIdleCallbacks
,
696 $this->trxPreCommitCallbacks
,
697 $this->trxEndCallbacks
699 foreach ( $callbacks as $callback ) {
700 $fnames[] = $callback[1];
707 public function isOpen() {
708 return $this->opened
;
711 public function setFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
712 if ( ( $flag & self
::DBO_IGNORE
) ) {
713 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
716 if ( $remember === self
::REMEMBER_PRIOR
) {
717 array_push( $this->priorFlags
, $this->flags
);
719 $this->flags |
= $flag;
722 public function clearFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
723 if ( ( $flag & self
::DBO_IGNORE
) ) {
724 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
727 if ( $remember === self
::REMEMBER_PRIOR
) {
728 array_push( $this->priorFlags
, $this->flags
);
730 $this->flags
&= ~
$flag;
733 public function restoreFlags( $state = self
::RESTORE_PRIOR
) {
734 if ( !$this->priorFlags
) {
738 if ( $state === self
::RESTORE_INITIAL
) {
739 $this->flags
= reset( $this->priorFlags
);
740 $this->priorFlags
= [];
742 $this->flags
= array_pop( $this->priorFlags
);
746 public function getFlag( $flag ) {
747 return !!( $this->flags
& $flag );
751 * @param string $name Class field name
753 * @deprecated Since 1.28
755 public function getProperty( $name ) {
759 public function getDomainID() {
760 return $this->currentDomain
->getId();
763 final public function getWikiID() {
764 return $this->getDomainID();
768 * Get information about an index into an object
769 * @param string $table Table name
770 * @param string $index Index name
771 * @param string $fname Calling function name
772 * @return mixed Database-specific index description class or false if the index does not exist
774 abstract function indexInfo( $table, $index, $fname = __METHOD__
);
777 * Wrapper for addslashes()
779 * @param string $s String to be slashed.
780 * @return string Slashed string.
782 abstract function strencode( $s );
785 * Set a custom error handler for logging errors during database connection
787 protected function installErrorHandler() {
788 $this->phpError
= false;
789 $this->htmlErrors
= ini_set( 'html_errors', '0' );
790 set_error_handler( [ $this, 'connectionErrorLogger' ] );
794 * Restore the previous error handler and return the last PHP error for this DB
796 * @return bool|string
798 protected function restoreErrorHandler() {
799 restore_error_handler();
800 if ( $this->htmlErrors
!== false ) {
801 ini_set( 'html_errors', $this->htmlErrors
);
804 return $this->getLastPHPError();
808 * @return string|bool Last PHP error for this DB (typically connection errors)
810 protected function getLastPHPError() {
811 if ( $this->phpError
) {
812 $error = preg_replace( '!\[<a.*</a>\]!', '', $this->phpError
);
813 $error = preg_replace( '!^.*?:\s?(.*)$!', '$1', $error );
822 * Error handler for logging errors during database connection
823 * This method should not be used outside of Database classes
826 * @param string $errstr
828 public function connectionErrorLogger( $errno, $errstr ) {
829 $this->phpError
= $errstr;
833 * Create a log context to pass to PSR-3 logger functions.
835 * @param array $extras Additional data to add to context
838 protected function getLogContext( array $extras = [] ) {
841 'db_server' => $this->server
,
842 'db_name' => $this->dbName
,
843 'db_user' => $this->user
,
849 public function close() {
851 // Resolve any dangling transaction first
852 if ( $this->trxLevel() ) {
853 // Meaningful transactions should ideally have been resolved by now
854 if ( $this->writesOrCallbacksPending() ) {
855 $this->queryLogger
->warning(
856 __METHOD__
. ": writes or callbacks still pending.",
857 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
860 // Check if it is possible to properly commit and trigger callbacks
861 if ( $this->trxEndCallbacksSuppressed
) {
862 throw new DBUnexpectedError(
864 __METHOD__
. ': callbacks are suppressed; cannot properly commit.'
867 // Commit the changes and run any callbacks as needed
868 $this->commit( __METHOD__
, self
::FLUSHING_INTERNAL
);
870 // Close the actual connection in the binding handle
871 $closed = $this->closeConnection();
873 // Sanity check that no callbacks are dangling
875 $this->trxIdleCallbacks ||
$this->trxPreCommitCallbacks ||
$this->trxEndCallbacks
877 throw new RuntimeException( "Transaction callbacks still pending." );
880 $closed = true; // already closed; nothing to do
883 $this->opened
= false;
889 * Make sure isOpen() returns true as a sanity check
891 * @throws DBUnexpectedError
893 protected function assertOpen() {
894 if ( !$this->isOpen() ) {
895 throw new DBUnexpectedError( $this, "DB connection was already closed." );
900 * Closes underlying database connection
902 * @return bool Whether connection was closed successfully
904 abstract protected function closeConnection();
907 * @param string $error Fallback error message, used if none is given by DB
908 * @throws DBConnectionError
910 public function reportConnectionError( $error = 'Unknown error' ) {
911 $myError = $this->lastError();
917 throw new DBConnectionError( $this, $error );
921 * Run a query and return a DBMS-dependent wrapper (that has all IResultWrapper methods)
923 * This might return things, such as mysqli_result, that do not formally implement
924 * IResultWrapper, but nonetheless implement all of its methods correctly
926 * @param string $sql SQL query.
927 * @return IResultWrapper|bool Iterator to feed to fetchObject/fetchRow; false on failure
929 abstract protected function doQuery( $sql );
932 * Determine whether a query writes to the DB.
933 * Should return true if unsure.
938 protected function isWriteQuery( $sql ) {
940 '/^(?:SELECT|BEGIN|ROLLBACK|COMMIT|SET|SHOW|EXPLAIN|\(SELECT)\b/i', $sql );
945 * @return string|null
947 protected function getQueryVerb( $sql ) {
948 return preg_match( '/^\s*([a-z]+)/i', $sql, $m ) ?
strtoupper( $m[1] ) : null;
952 * Determine whether a SQL statement is sensitive to isolation level.
953 * A SQL statement is considered transactable if its result could vary
954 * depending on the transaction isolation level. Operational commands
955 * such as 'SET' and 'SHOW' are not considered to be transactable.
960 protected function isTransactableQuery( $sql ) {
962 $this->getQueryVerb( $sql ),
963 [ 'BEGIN', 'COMMIT', 'ROLLBACK', 'SHOW', 'SET', 'CREATE', 'ALTER' ],
969 * @param string $sql A SQL query
970 * @return bool Whether $sql is SQL for TEMPORARY table operation
972 protected function registerTempTableOperation( $sql ) {
974 '/^CREATE\s+TEMPORARY\s+TABLE\s+(?:IF\s+NOT\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
978 $this->sessionTempTables
[$matches[1]] = 1;
981 } elseif ( preg_match(
982 '/^DROP\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
986 $isTemp = isset( $this->sessionTempTables
[$matches[1]] );
987 unset( $this->sessionTempTables
[$matches[1]] );
990 } elseif ( preg_match(
991 '/^TRUNCATE\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
995 return isset( $this->sessionTempTables
[$matches[1]] );
996 } elseif ( preg_match(
997 '/^(?:INSERT\s+(?:\w+\s+)?INTO|UPDATE|DELETE\s+FROM)\s+[`"\']?(\w+)[`"\']?/i',
1001 return isset( $this->sessionTempTables
[$matches[1]] );
1007 public function query( $sql, $fname = __METHOD__
, $tempIgnore = false ) {
1008 $priorWritesPending = $this->writesOrCallbacksPending();
1009 $this->lastQuery
= $sql;
1011 $isWrite = $this->isWriteQuery( $sql );
1013 $isNonTempWrite = !$this->registerTempTableOperation( $sql );
1015 $isNonTempWrite = false;
1019 if ( $this->getLBInfo( 'replica' ) === true ) {
1022 'Write operations are not allowed on replica database connections.'
1025 # In theory, non-persistent writes are allowed in read-only mode, but due to things
1026 # like https://bugs.mysql.com/bug.php?id=33669 that might not work anyway...
1027 $reason = $this->getReadOnlyReason();
1028 if ( $reason !== false ) {
1029 throw new DBReadOnlyError( $this, "Database is read-only: $reason" );
1031 # Set a flag indicating that writes have been done
1032 $this->lastWriteTime
= microtime( true );
1035 # Add trace comment to the begin of the sql string, right after the operator.
1036 # Or, for one-word queries (like "BEGIN" or COMMIT") add it to the end (T44598)
1037 $commentedSql = preg_replace( '/\s|$/', " /* $fname {$this->agent} */ ", $sql, 1 );
1039 # Start implicit transactions that wrap the request if DBO_TRX is enabled
1040 if ( !$this->trxLevel
&& $this->getFlag( self
::DBO_TRX
)
1041 && $this->isTransactableQuery( $sql )
1043 $this->begin( __METHOD__
. " ($fname)", self
::TRANSACTION_INTERNAL
);
1044 $this->trxAutomatic
= true;
1047 # Keep track of whether the transaction has write queries pending
1048 if ( $this->trxLevel
&& !$this->trxDoneWrites
&& $isWrite ) {
1049 $this->trxDoneWrites
= true;
1050 $this->trxProfiler
->transactionWritingIn(
1051 $this->server
, $this->dbName
, $this->trxShortId
);
1054 if ( $this->getFlag( self
::DBO_DEBUG
) ) {
1055 $this->queryLogger
->debug( "{$this->dbName} {$commentedSql}" );
1058 # Avoid fatals if close() was called
1059 $this->assertOpen();
1061 # Send the query to the server and fetch any corresponding errors
1062 $ret = $this->doProfiledQuery( $sql, $commentedSql, $isNonTempWrite, $fname );
1063 $lastError = $this->lastError();
1064 $lastErrno = $this->lastErrno();
1066 # Try reconnecting if the connection was lost
1067 if ( $ret === false && $this->wasConnectionLoss() ) {
1068 # Check if any meaningful session state was lost
1069 $recoverable = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
1070 # Update session state tracking and try to restore the connection
1071 $reconnected = $this->replaceLostConnection( __METHOD__
);
1072 # Silently resend the query to the server if it is safe and possible
1073 if ( $reconnected && $recoverable ) {
1074 $ret = $this->doProfiledQuery( $sql, $commentedSql, $isNonTempWrite, $fname );
1075 $lastError = $this->lastError();
1076 $lastErrno = $this->lastErrno();
1078 if ( $ret === false && $this->wasConnectionLoss() ) {
1079 # Query probably causes disconnects; reconnect and do not re-run it
1080 $this->replaceLostConnection( __METHOD__
);
1085 if ( $ret === false ) {
1086 # Deadlocks cause the entire transaction to abort, not just the statement.
1087 # https://dev.mysql.com/doc/refman/5.7/en/innodb-error-handling.html
1088 # https://www.postgresql.org/docs/9.1/static/explicit-locking.html
1089 if ( $this->wasDeadlock() ) {
1090 if ( $this->explicitTrxActive() ||
$priorWritesPending ) {
1091 $tempIgnore = false; // not recoverable
1093 # Usually the transaction is rolled back to BEGIN, leaving an empty transaction.
1094 # Destroy any such transaction so the rollback callbacks run in AUTO-COMMIT mode
1095 # as normal. Also, if DBO_TRX is set and an explicit transaction rolled back here,
1096 # further queries should be back in AUTO-COMMIT mode, not stuck in a transaction.
1097 $this->doRollback( __METHOD__
);
1098 # Update state tracking to reflect transaction loss
1099 $this->handleTransactionLoss();
1102 $this->reportQueryError( $lastError, $lastErrno, $sql, $fname, $tempIgnore );
1105 return $this->resultObject( $ret );
1109 * Wrapper for query() that also handles profiling, logging, and affected row count updates
1111 * @param string $sql Original SQL query
1112 * @param string $commentedSql SQL query with debugging/trace comment
1113 * @param bool $isWrite Whether the query is a (non-temporary) write operation
1114 * @param string $fname Name of the calling function
1115 * @return bool|ResultWrapper True for a successful write query, ResultWrapper
1116 * object for a successful read query, or false on failure
1118 private function doProfiledQuery( $sql, $commentedSql, $isWrite, $fname ) {
1119 $isMaster = !is_null( $this->getLBInfo( 'master' ) );
1120 # generalizeSQL() will probably cut down the query to reasonable
1121 # logging size most of the time. The substr is really just a sanity check.
1123 $queryProf = 'query-m: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1125 $queryProf = 'query: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1128 # Include query transaction state
1129 $queryProf .= $this->trxShortId ?
" [TRX#{$this->trxShortId}]" : "";
1131 $startTime = microtime( true );
1132 if ( $this->profiler
) {
1133 call_user_func( [ $this->profiler
, 'profileIn' ], $queryProf );
1135 $this->affectedRowCount
= null;
1136 $ret = $this->doQuery( $commentedSql );
1137 $this->affectedRowCount
= $this->affectedRows();
1138 if ( $this->profiler
) {
1139 call_user_func( [ $this->profiler
, 'profileOut' ], $queryProf );
1141 $queryRuntime = max( microtime( true ) - $startTime, 0.0 );
1143 unset( $queryProfSection ); // profile out (if set)
1145 if ( $ret !== false ) {
1146 $this->lastPing
= $startTime;
1147 if ( $isWrite && $this->trxLevel
) {
1148 $this->updateTrxWriteQueryTime( $sql, $queryRuntime, $this->affectedRows() );
1149 $this->trxWriteCallers
[] = $fname;
1153 if ( $sql === self
::PING_QUERY
) {
1154 $this->rttEstimate
= $queryRuntime;
1157 $this->trxProfiler
->recordQueryCompletion(
1158 $queryProf, $startTime, $isWrite, $this->affectedRows()
1160 $this->queryLogger
->debug( $sql, [
1162 'master' => $isMaster,
1163 'runtime' => $queryRuntime,
1170 * Update the estimated run-time of a query, not counting large row lock times
1172 * LoadBalancer can be set to rollback transactions that will create huge replication
1173 * lag. It bases this estimate off of pendingWriteQueryDuration(). Certain simple
1174 * queries, like inserting a row can take a long time due to row locking. This method
1175 * uses some simple heuristics to discount those cases.
1177 * @param string $sql A SQL write query
1178 * @param float $runtime Total runtime, including RTT
1179 * @param int $affected Affected row count
1181 private function updateTrxWriteQueryTime( $sql, $runtime, $affected ) {
1182 // Whether this is indicative of replica DB runtime (except for RBR or ws_repl)
1183 $indicativeOfReplicaRuntime = true;
1184 if ( $runtime > self
::SLOW_WRITE_SEC
) {
1185 $verb = $this->getQueryVerb( $sql );
1186 // insert(), upsert(), replace() are fast unless bulky in size or blocked on locks
1187 if ( $verb === 'INSERT' ) {
1188 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
;
1189 } elseif ( $verb === 'REPLACE' ) {
1190 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
/ 2;
1194 $this->trxWriteDuration +
= $runtime;
1195 $this->trxWriteQueryCount +
= 1;
1196 $this->trxWriteAffectedRows +
= $affected;
1197 if ( $indicativeOfReplicaRuntime ) {
1198 $this->trxWriteAdjDuration +
= $runtime;
1199 $this->trxWriteAdjQueryCount +
= 1;
1204 * Determine whether or not it is safe to retry queries after a database
1205 * connection is lost
1207 * @param string $sql SQL query
1208 * @param bool $priorWritesPending Whether there is a transaction open with
1209 * possible write queries or transaction pre-commit/idle callbacks
1210 * waiting on it to finish.
1211 * @return bool True if it is safe to retry the query, false otherwise
1213 private function canRecoverFromDisconnect( $sql, $priorWritesPending ) {
1214 # Transaction dropped; this can mean lost writes, or REPEATABLE-READ snapshots.
1215 # Dropped connections also mean that named locks are automatically released.
1216 # Only allow error suppression in autocommit mode or when the lost transaction
1217 # didn't matter anyway (aside from DBO_TRX snapshot loss).
1218 if ( $this->namedLocksHeld
) {
1219 return false; // possible critical section violation
1220 } elseif ( $this->sessionTempTables
) {
1221 return false; // tables might be queried latter
1222 } elseif ( $sql === 'COMMIT' ) {
1223 return !$priorWritesPending; // nothing written anyway? (T127428)
1224 } elseif ( $sql === 'ROLLBACK' ) {
1225 return true; // transaction lost...which is also what was requested :)
1226 } elseif ( $this->explicitTrxActive() ) {
1227 return false; // don't drop atomocity
1228 } elseif ( $priorWritesPending ) {
1229 return false; // prior writes lost from implicit transaction
1236 * Clean things up after session (and thus transaction) loss
1238 private function handleSessionLoss() {
1239 // Clean up tracking of session-level things...
1240 // https://dev.mysql.com/doc/refman/5.7/en/implicit-commit.html
1241 // https://www.postgresql.org/docs/9.1/static/sql-createtable.html (ignoring ON COMMIT)
1242 $this->sessionTempTables
= [];
1243 // https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1244 // https://www.postgresql.org/docs/9.4/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1245 $this->namedLocksHeld
= [];
1246 // Session loss implies transaction loss
1247 $this->handleTransactionLoss();
1251 * Clean things up after transaction loss
1253 private function handleTransactionLoss() {
1254 $this->trxLevel
= 0;
1255 $this->trxAtomicCounter
= 0;
1256 $this->trxIdleCallbacks
= []; // T67263; transaction already lost
1257 $this->trxPreCommitCallbacks
= []; // T67263; transaction already lost
1259 // Handle callbacks in trxEndCallbacks, e.g. onTransactionResolution().
1260 // If callback suppression is set then the array will remain unhandled.
1261 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
1262 } catch ( Exception
$ex ) {
1263 // Already logged; move on...
1266 // Handle callbacks in trxRecurringCallbacks, e.g. setTransactionListener()
1267 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
1268 } catch ( Exception
$ex ) {
1269 // Already logged; move on...
1274 * Checks whether the cause of the error is detected to be a timeout.
1276 * It returns false by default, and not all engines support detecting this yet.
1277 * If this returns false, it will be treated as a generic query error.
1279 * @param string $error Error text
1280 * @param int $errno Error number
1283 protected function wasQueryTimeout( $error, $errno ) {
1288 * Report a query error. Log the error, and if neither the object ignore
1289 * flag nor the $tempIgnore flag is set, throw a DBQueryError.
1291 * @param string $error
1293 * @param string $sql
1294 * @param string $fname
1295 * @param bool $tempIgnore
1296 * @throws DBQueryError
1298 public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
1299 if ( $tempIgnore ) {
1300 $this->queryLogger
->debug( "SQL ERROR (ignored): $error\n" );
1302 $sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
1303 $this->queryLogger
->error(
1304 "{fname}\t{db_server}\t{errno}\t{error}\t{sql1line}",
1305 $this->getLogContext( [
1306 'method' => __METHOD__
,
1309 'sql1line' => $sql1line,
1313 $this->queryLogger
->debug( "SQL ERROR: " . $error . "\n" );
1314 $wasQueryTimeout = $this->wasQueryTimeout( $error, $errno );
1315 if ( $wasQueryTimeout ) {
1316 throw new DBQueryTimeoutError( $this, $error, $errno, $sql, $fname );
1318 throw new DBQueryError( $this, $error, $errno, $sql, $fname );
1323 public function freeResult( $res ) {
1326 public function selectField(
1327 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1329 if ( $var === '*' ) { // sanity
1330 throw new DBUnexpectedError( $this, "Cannot use a * field: got '$var'" );
1333 if ( !is_array( $options ) ) {
1334 $options = [ $options ];
1337 $options['LIMIT'] = 1;
1339 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1340 if ( $res === false ||
!$this->numRows( $res ) ) {
1344 $row = $this->fetchRow( $res );
1346 if ( $row !== false ) {
1347 return reset( $row );
1353 public function selectFieldValues(
1354 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1356 if ( $var === '*' ) { // sanity
1357 throw new DBUnexpectedError( $this, "Cannot use a * field" );
1358 } elseif ( !is_string( $var ) ) { // sanity
1359 throw new DBUnexpectedError( $this, "Cannot use an array of fields" );
1362 if ( !is_array( $options ) ) {
1363 $options = [ $options ];
1366 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1367 if ( $res === false ) {
1372 foreach ( $res as $row ) {
1373 $values[] = $row->$var;
1380 * Returns an optional USE INDEX clause to go after the table, and a
1381 * string to go at the end of the query.
1383 * @param array $options Associative array of options to be turned into
1384 * an SQL query, valid keys are listed in the function.
1386 * @see Database::select()
1388 protected function makeSelectOptions( $options ) {
1389 $preLimitTail = $postLimitTail = '';
1394 foreach ( $options as $key => $option ) {
1395 if ( is_numeric( $key ) ) {
1396 $noKeyOptions[$option] = true;
1400 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1402 $preLimitTail .= $this->makeOrderBy( $options );
1404 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1405 $postLimitTail .= ' FOR UPDATE';
1408 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1409 $postLimitTail .= ' LOCK IN SHARE MODE';
1412 if ( isset( $noKeyOptions['DISTINCT'] ) ||
isset( $noKeyOptions['DISTINCTROW'] ) ) {
1413 $startOpts .= 'DISTINCT';
1416 # Various MySQL extensions
1417 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) {
1418 $startOpts .= ' /*! STRAIGHT_JOIN */';
1421 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) {
1422 $startOpts .= ' HIGH_PRIORITY';
1425 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) {
1426 $startOpts .= ' SQL_BIG_RESULT';
1429 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) {
1430 $startOpts .= ' SQL_BUFFER_RESULT';
1433 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) {
1434 $startOpts .= ' SQL_SMALL_RESULT';
1437 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) {
1438 $startOpts .= ' SQL_CALC_FOUND_ROWS';
1441 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) {
1442 $startOpts .= ' SQL_CACHE';
1445 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) {
1446 $startOpts .= ' SQL_NO_CACHE';
1449 if ( isset( $options['USE INDEX'] ) && is_string( $options['USE INDEX'] ) ) {
1450 $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1454 if ( isset( $options['IGNORE INDEX'] ) && is_string( $options['IGNORE INDEX'] ) ) {
1455 $ignoreIndex = $this->ignoreIndexClause( $options['IGNORE INDEX'] );
1460 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1464 * Returns an optional GROUP BY with an optional HAVING
1466 * @param array $options Associative array of options
1468 * @see Database::select()
1471 protected function makeGroupByWithHaving( $options ) {
1473 if ( isset( $options['GROUP BY'] ) ) {
1474 $gb = is_array( $options['GROUP BY'] )
1475 ?
implode( ',', $options['GROUP BY'] )
1476 : $options['GROUP BY'];
1477 $sql .= ' GROUP BY ' . $gb;
1479 if ( isset( $options['HAVING'] ) ) {
1480 $having = is_array( $options['HAVING'] )
1481 ?
$this->makeList( $options['HAVING'], self
::LIST_AND
)
1482 : $options['HAVING'];
1483 $sql .= ' HAVING ' . $having;
1490 * Returns an optional ORDER BY
1492 * @param array $options Associative array of options
1494 * @see Database::select()
1497 protected function makeOrderBy( $options ) {
1498 if ( isset( $options['ORDER BY'] ) ) {
1499 $ob = is_array( $options['ORDER BY'] )
1500 ?
implode( ',', $options['ORDER BY'] )
1501 : $options['ORDER BY'];
1503 return ' ORDER BY ' . $ob;
1509 public function select( $table, $vars, $conds = '', $fname = __METHOD__
,
1510 $options = [], $join_conds = [] ) {
1511 $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
1513 return $this->query( $sql, $fname );
1516 public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__
,
1517 $options = [], $join_conds = []
1519 if ( is_array( $vars ) ) {
1520 $vars = implode( ',', $this->fieldNamesWithAlias( $vars ) );
1523 $options = (array)$options;
1524 $useIndexes = ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1525 ?
$options['USE INDEX']
1528 isset( $options['IGNORE INDEX'] ) &&
1529 is_array( $options['IGNORE INDEX'] )
1531 ?
$options['IGNORE INDEX']
1534 if ( is_array( $table ) ) {
1536 $this->tableNamesWithIndexClauseOrJOIN(
1537 $table, $useIndexes, $ignoreIndexes, $join_conds );
1538 } elseif ( $table != '' ) {
1540 $this->tableNamesWithIndexClauseOrJOIN(
1541 [ $table ], $useIndexes, $ignoreIndexes, [] );
1546 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ) =
1547 $this->makeSelectOptions( $options );
1549 if ( is_array( $conds ) ) {
1550 $conds = $this->makeList( $conds, self
::LIST_AND
);
1553 if ( $conds === null ||
$conds === false ) {
1554 $this->queryLogger
->warning(
1558 . ' with incorrect parameters: $conds must be a string or an array'
1563 if ( $conds === '' ) {
1564 $sql = "SELECT $startOpts $vars $from $useIndex $ignoreIndex $preLimitTail";
1565 } elseif ( is_string( $conds ) ) {
1566 $sql = "SELECT $startOpts $vars $from $useIndex $ignoreIndex " .
1567 "WHERE $conds $preLimitTail";
1569 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
1572 if ( isset( $options['LIMIT'] ) ) {
1573 $sql = $this->limitResult( $sql, $options['LIMIT'],
1574 isset( $options['OFFSET'] ) ?
$options['OFFSET'] : false );
1576 $sql = "$sql $postLimitTail";
1578 if ( isset( $options['EXPLAIN'] ) ) {
1579 $sql = 'EXPLAIN ' . $sql;
1585 public function selectRow( $table, $vars, $conds, $fname = __METHOD__
,
1586 $options = [], $join_conds = []
1588 $options = (array)$options;
1589 $options['LIMIT'] = 1;
1590 $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
1592 if ( $res === false ) {
1596 if ( !$this->numRows( $res ) ) {
1600 $obj = $this->fetchObject( $res );
1605 public function estimateRowCount(
1606 $table, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1608 $conds = $this->normalizeConditions( $conds, $fname );
1609 $column = $this->extractSingleFieldFromList( $var );
1610 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1611 $conds[] = "$column IS NOT NULL";
1614 $res = $this->select(
1615 $table, [ 'rowcount' => 'COUNT(*)' ], $conds, $fname, $options, $join_conds
1617 $row = $res ?
$this->fetchRow( $res ) : [];
1619 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1622 public function selectRowCount(
1623 $tables, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1625 $conds = $this->normalizeConditions( $conds, $fname );
1626 $column = $this->extractSingleFieldFromList( $var );
1627 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1628 $conds[] = "$column IS NOT NULL";
1631 $res = $this->select(
1633 'tmp_count' => $this->buildSelectSubquery(
1642 [ 'rowcount' => 'COUNT(*)' ],
1646 $row = $res ?
$this->fetchRow( $res ) : [];
1648 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1652 * @param array|string $conds
1653 * @param string $fname
1656 final protected function normalizeConditions( $conds, $fname ) {
1657 if ( $conds === null ||
$conds === false ) {
1658 $this->queryLogger
->warning(
1662 . ' with incorrect parameters: $conds must be a string or an array'
1667 if ( !is_array( $conds ) ) {
1668 $conds = ( $conds === '' ) ?
[] : [ $conds ];
1675 * @param array|string $var Field parameter in the style of select()
1676 * @return string|null Column name or null; ignores aliases
1677 * @throws DBUnexpectedError Errors out if multiple columns are given
1679 final protected function extractSingleFieldFromList( $var ) {
1680 if ( is_array( $var ) ) {
1683 } elseif ( count( $var ) == 1 ) {
1684 $column = isset( $var[0] ) ?
$var[0] : reset( $var );
1686 throw new DBUnexpectedError( $this, __METHOD__
. ': got multiple columns.' );
1696 * Removes most variables from an SQL query and replaces them with X or N for numbers.
1697 * It's only slightly flawed. Don't use for anything important.
1699 * @param string $sql A SQL Query
1703 protected static function generalizeSQL( $sql ) {
1704 # This does the same as the regexp below would do, but in such a way
1705 # as to avoid crashing php on some large strings.
1706 # $sql = preg_replace( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql );
1708 $sql = str_replace( "\\\\", '', $sql );
1709 $sql = str_replace( "\\'", '', $sql );
1710 $sql = str_replace( "\\\"", '', $sql );
1711 $sql = preg_replace( "/'.*'/s", "'X'", $sql );
1712 $sql = preg_replace( '/".*"/s', "'X'", $sql );
1714 # All newlines, tabs, etc replaced by single space
1715 $sql = preg_replace( '/\s+/', ' ', $sql );
1718 # except the ones surrounded by characters, e.g. l10n
1719 $sql = preg_replace( '/-?\d+(,-?\d+)+/s', 'N,...,N', $sql );
1720 $sql = preg_replace( '/(?<![a-zA-Z])-?\d+(?![a-zA-Z])/s', 'N', $sql );
1725 public function fieldExists( $table, $field, $fname = __METHOD__
) {
1726 $info = $this->fieldInfo( $table, $field );
1731 public function indexExists( $table, $index, $fname = __METHOD__
) {
1732 if ( !$this->tableExists( $table ) ) {
1736 $info = $this->indexInfo( $table, $index, $fname );
1737 if ( is_null( $info ) ) {
1740 return $info !== false;
1744 public function tableExists( $table, $fname = __METHOD__
) {
1745 $tableRaw = $this->tableName( $table, 'raw' );
1746 if ( isset( $this->sessionTempTables
[$tableRaw] ) ) {
1747 return true; // already known to exist
1750 $table = $this->tableName( $table );
1751 $ignoreErrors = true;
1752 $res = $this->query( "SELECT 1 FROM $table LIMIT 1", $fname, $ignoreErrors );
1757 public function indexUnique( $table, $index ) {
1758 $indexInfo = $this->indexInfo( $table, $index );
1760 if ( !$indexInfo ) {
1764 return !$indexInfo[0]->Non_unique
;
1768 * Helper for Database::insert().
1770 * @param array $options
1773 protected function makeInsertOptions( $options ) {
1774 return implode( ' ', $options );
1777 public function insert( $table, $a, $fname = __METHOD__
, $options = [] ) {
1778 # No rows to insert, easy just return now
1779 if ( !count( $a ) ) {
1783 $table = $this->tableName( $table );
1785 if ( !is_array( $options ) ) {
1786 $options = [ $options ];
1790 if ( isset( $options['fileHandle'] ) ) {
1791 $fh = $options['fileHandle'];
1793 $options = $this->makeInsertOptions( $options );
1795 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
1797 $keys = array_keys( $a[0] );
1800 $keys = array_keys( $a );
1803 $sql = 'INSERT ' . $options .
1804 " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
1808 foreach ( $a as $row ) {
1814 $sql .= '(' . $this->makeList( $row ) . ')';
1817 $sql .= '(' . $this->makeList( $a ) . ')';
1820 if ( $fh !== null && false === fwrite( $fh, $sql ) ) {
1822 } elseif ( $fh !== null ) {
1826 return (bool)$this->query( $sql, $fname );
1830 * Make UPDATE options array for Database::makeUpdateOptions
1832 * @param array $options
1835 protected function makeUpdateOptionsArray( $options ) {
1836 if ( !is_array( $options ) ) {
1837 $options = [ $options ];
1842 if ( in_array( 'IGNORE', $options ) ) {
1850 * Make UPDATE options for the Database::update function
1852 * @param array $options The options passed to Database::update
1855 protected function makeUpdateOptions( $options ) {
1856 $opts = $this->makeUpdateOptionsArray( $options );
1858 return implode( ' ', $opts );
1861 public function update( $table, $values, $conds, $fname = __METHOD__
, $options = [] ) {
1862 $table = $this->tableName( $table );
1863 $opts = $this->makeUpdateOptions( $options );
1864 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, self
::LIST_SET
);
1866 if ( $conds !== [] && $conds !== '*' ) {
1867 $sql .= " WHERE " . $this->makeList( $conds, self
::LIST_AND
);
1870 return (bool)$this->query( $sql, $fname );
1873 public function makeList( $a, $mode = self
::LIST_COMMA
) {
1874 if ( !is_array( $a ) ) {
1875 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
1881 foreach ( $a as $field => $value ) {
1883 if ( $mode == self
::LIST_AND
) {
1885 } elseif ( $mode == self
::LIST_OR
) {
1894 if ( ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_numeric( $field ) ) {
1895 $list .= "($value)";
1896 } elseif ( $mode == self
::LIST_SET
&& is_numeric( $field ) ) {
1899 ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_array( $value )
1901 // Remove null from array to be handled separately if found
1902 $includeNull = false;
1903 foreach ( array_keys( $value, null, true ) as $nullKey ) {
1904 $includeNull = true;
1905 unset( $value[$nullKey] );
1907 if ( count( $value ) == 0 && !$includeNull ) {
1908 throw new InvalidArgumentException(
1909 __METHOD__
. ": empty input for field $field" );
1910 } elseif ( count( $value ) == 0 ) {
1911 // only check if $field is null
1912 $list .= "$field IS NULL";
1914 // IN clause contains at least one valid element
1915 if ( $includeNull ) {
1916 // Group subconditions to ensure correct precedence
1919 if ( count( $value ) == 1 ) {
1920 // Special-case single values, as IN isn't terribly efficient
1921 // Don't necessarily assume the single key is 0; we don't
1922 // enforce linear numeric ordering on other arrays here.
1923 $value = array_values( $value )[0];
1924 $list .= $field . " = " . $this->addQuotes( $value );
1926 $list .= $field . " IN (" . $this->makeList( $value ) . ") ";
1928 // if null present in array, append IS NULL
1929 if ( $includeNull ) {
1930 $list .= " OR $field IS NULL)";
1933 } elseif ( $value === null ) {
1934 if ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) {
1935 $list .= "$field IS ";
1936 } elseif ( $mode == self
::LIST_SET
) {
1937 $list .= "$field = ";
1942 $mode == self
::LIST_AND ||
$mode == self
::LIST_OR ||
$mode == self
::LIST_SET
1944 $list .= "$field = ";
1946 $list .= $mode == self
::LIST_NAMES ?
$value : $this->addQuotes( $value );
1953 public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
1956 foreach ( $data as $base => $sub ) {
1957 if ( count( $sub ) ) {
1958 $conds[] = $this->makeList(
1959 [ $baseKey => $base, $subKey => array_keys( $sub ) ],
1965 return $this->makeList( $conds, self
::LIST_OR
);
1967 // Nothing to search for...
1972 public function aggregateValue( $valuedata, $valuename = 'value' ) {
1976 public function bitNot( $field ) {
1980 public function bitAnd( $fieldLeft, $fieldRight ) {
1981 return "($fieldLeft & $fieldRight)";
1984 public function bitOr( $fieldLeft, $fieldRight ) {
1985 return "($fieldLeft | $fieldRight)";
1988 public function buildConcat( $stringList ) {
1989 return 'CONCAT(' . implode( ',', $stringList ) . ')';
1992 public function buildGroupConcatField(
1993 $delim, $table, $field, $conds = '', $join_conds = []
1995 $fld = "GROUP_CONCAT($field SEPARATOR " . $this->addQuotes( $delim ) . ')';
1997 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
2000 public function buildSubstring( $input, $startPosition, $length = null ) {
2001 $this->assertBuildSubstringParams( $startPosition, $length );
2002 $functionBody = "$input FROM $startPosition";
2003 if ( $length !== null ) {
2004 $functionBody .= " FOR $length";
2006 return 'SUBSTRING(' . $functionBody . ')';
2010 * Check type and bounds for parameters to self::buildSubstring()
2012 * All supported databases have substring functions that behave the same for
2013 * positive $startPosition and non-negative $length, but behaviors differ when
2014 * given 0 or negative $startPosition or negative $length. The simplest
2015 * solution to that is to just forbid those values.
2017 * @param int $startPosition
2018 * @param int|null $length
2021 protected function assertBuildSubstringParams( $startPosition, $length ) {
2022 if ( !is_int( $startPosition ) ||
$startPosition <= 0 ) {
2023 throw new InvalidArgumentException(
2024 '$startPosition must be a positive integer'
2027 if ( !( is_int( $length ) && $length >= 0 ||
$length === null ) ) {
2028 throw new InvalidArgumentException(
2029 '$length must be null or an integer greater than or equal to 0'
2034 public function buildStringCast( $field ) {
2038 public function buildIntegerCast( $field ) {
2039 return 'CAST( ' . $field . ' AS INTEGER )';
2042 public function buildSelectSubquery(
2043 $table, $vars, $conds = '', $fname = __METHOD__
,
2044 $options = [], $join_conds = []
2046 return new Subquery(
2047 $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds )
2051 public function databasesAreIndependent() {
2055 public function selectDB( $db ) {
2056 # Stub. Shouldn't cause serious problems if it's not overridden, but
2057 # if your database engine supports a concept similar to MySQL's
2058 # databases you may as well.
2059 $this->dbName
= $db;
2064 public function getDBname() {
2065 return $this->dbName
;
2068 public function getServer() {
2069 return $this->server
;
2072 public function tableName( $name, $format = 'quoted' ) {
2073 if ( $name instanceof Subquery
) {
2074 throw new DBUnexpectedError(
2076 __METHOD__
. ': got Subquery instance when expecting a string.'
2080 # Skip the entire process when we have a string quoted on both ends.
2081 # Note that we check the end so that we will still quote any use of
2082 # use of `database`.table. But won't break things if someone wants
2083 # to query a database table with a dot in the name.
2084 if ( $this->isQuotedIdentifier( $name ) ) {
2088 # Lets test for any bits of text that should never show up in a table
2089 # name. Basically anything like JOIN or ON which are actually part of
2090 # SQL queries, but may end up inside of the table value to combine
2091 # sql. Such as how the API is doing.
2092 # Note that we use a whitespace test rather than a \b test to avoid
2093 # any remote case where a word like on may be inside of a table name
2094 # surrounded by symbols which may be considered word breaks.
2095 if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) {
2096 $this->queryLogger
->warning(
2097 __METHOD__
. ": use of subqueries is not supported this way.",
2098 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
2104 # Split database and table into proper variables.
2105 list( $database, $schema, $prefix, $table ) = $this->qualifiedTableComponents( $name );
2107 # Quote $table and apply the prefix if not quoted.
2108 # $tableName might be empty if this is called from Database::replaceVars()
2109 $tableName = "{$prefix}{$table}";
2110 if ( $format === 'quoted'
2111 && !$this->isQuotedIdentifier( $tableName )
2112 && $tableName !== ''
2114 $tableName = $this->addIdentifierQuotes( $tableName );
2117 # Quote $schema and $database and merge them with the table name if needed
2118 $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
2119 $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
2125 * Get the table components needed for a query given the currently selected database
2127 * @param string $name Table name in the form of db.schema.table, db.table, or table
2128 * @return array (DB name or "" for default, schema name, table prefix, table name)
2130 protected function qualifiedTableComponents( $name ) {
2131 # We reverse the explode so that database.table and table both output the correct table.
2132 $dbDetails = explode( '.', $name, 3 );
2133 if ( count( $dbDetails ) == 3 ) {
2134 list( $database, $schema, $table ) = $dbDetails;
2135 # We don't want any prefix added in this case
2137 } elseif ( count( $dbDetails ) == 2 ) {
2138 list( $database, $table ) = $dbDetails;
2139 # We don't want any prefix added in this case
2141 # In dbs that support it, $database may actually be the schema
2142 # but that doesn't affect any of the functionality here
2145 list( $table ) = $dbDetails;
2146 if ( isset( $this->tableAliases
[$table] ) ) {
2147 $database = $this->tableAliases
[$table]['dbname'];
2148 $schema = is_string( $this->tableAliases
[$table]['schema'] )
2149 ?
$this->tableAliases
[$table]['schema']
2151 $prefix = is_string( $this->tableAliases
[$table]['prefix'] )
2152 ?
$this->tableAliases
[$table]['prefix']
2153 : $this->tablePrefix
;
2156 $schema = $this->schema
; # Default schema
2157 $prefix = $this->tablePrefix
; # Default prefix
2161 return [ $database, $schema, $prefix, $table ];
2165 * @param string|null $namespace Database or schema
2166 * @param string $relation Name of table, view, sequence, etc...
2167 * @param string $format One of (raw, quoted)
2168 * @return string Relation name with quoted and merged $namespace as needed
2170 private function prependDatabaseOrSchema( $namespace, $relation, $format ) {
2171 if ( strlen( $namespace ) ) {
2172 if ( $format === 'quoted' && !$this->isQuotedIdentifier( $namespace ) ) {
2173 $namespace = $this->addIdentifierQuotes( $namespace );
2175 $relation = $namespace . '.' . $relation;
2181 public function tableNames() {
2182 $inArray = func_get_args();
2185 foreach ( $inArray as $name ) {
2186 $retVal[$name] = $this->tableName( $name );
2192 public function tableNamesN() {
2193 $inArray = func_get_args();
2196 foreach ( $inArray as $name ) {
2197 $retVal[] = $this->tableName( $name );
2204 * Get an aliased table name
2206 * This returns strings like "tableName AS newTableName" for aliased tables
2207 * and "(SELECT * from tableA) newTablename" for subqueries (e.g. derived tables)
2209 * @see Database::tableName()
2210 * @param string|Subquery $table Table name or object with a 'sql' field
2211 * @param string|bool $alias Table alias (optional)
2212 * @return string SQL name for aliased table. Will not alias a table to its own name
2214 protected function tableNameWithAlias( $table, $alias = false ) {
2215 if ( is_string( $table ) ) {
2216 $quotedTable = $this->tableName( $table );
2217 } elseif ( $table instanceof Subquery
) {
2218 $quotedTable = (string)$table;
2220 throw new InvalidArgumentException( "Table must be a string or Subquery." );
2223 if ( !strlen( $alias ) ||
$alias === $table ) {
2224 if ( $table instanceof Subquery
) {
2225 throw new InvalidArgumentException( "Subquery table missing alias." );
2228 return $quotedTable;
2230 return $quotedTable . ' ' . $this->addIdentifierQuotes( $alias );
2235 * Gets an array of aliased table names
2237 * @param array $tables [ [alias] => table ]
2238 * @return string[] See tableNameWithAlias()
2240 protected function tableNamesWithAlias( $tables ) {
2242 foreach ( $tables as $alias => $table ) {
2243 if ( is_numeric( $alias ) ) {
2246 $retval[] = $this->tableNameWithAlias( $table, $alias );
2253 * Get an aliased field name
2254 * e.g. fieldName AS newFieldName
2256 * @param string $name Field name
2257 * @param string|bool $alias Alias (optional)
2258 * @return string SQL name for aliased field. Will not alias a field to its own name
2260 protected function fieldNameWithAlias( $name, $alias = false ) {
2261 if ( !$alias ||
(string)$alias === (string)$name ) {
2264 return $name . ' AS ' . $this->addIdentifierQuotes( $alias ); // PostgreSQL needs AS
2269 * Gets an array of aliased field names
2271 * @param array $fields [ [alias] => field ]
2272 * @return string[] See fieldNameWithAlias()
2274 protected function fieldNamesWithAlias( $fields ) {
2276 foreach ( $fields as $alias => $field ) {
2277 if ( is_numeric( $alias ) ) {
2280 $retval[] = $this->fieldNameWithAlias( $field, $alias );
2287 * Get the aliased table name clause for a FROM clause
2288 * which might have a JOIN and/or USE INDEX or IGNORE INDEX clause
2290 * @param array $tables ( [alias] => table )
2291 * @param array $use_index Same as for select()
2292 * @param array $ignore_index Same as for select()
2293 * @param array $join_conds Same as for select()
2296 protected function tableNamesWithIndexClauseOrJOIN(
2297 $tables, $use_index = [], $ignore_index = [], $join_conds = []
2301 $use_index = (array)$use_index;
2302 $ignore_index = (array)$ignore_index;
2303 $join_conds = (array)$join_conds;
2305 foreach ( $tables as $alias => $table ) {
2306 if ( !is_string( $alias ) ) {
2307 // No alias? Set it equal to the table name
2311 if ( is_array( $table ) ) {
2312 // A parenthesized group
2313 if ( count( $table ) > 1 ) {
2314 $joinedTable = '(' .
2315 $this->tableNamesWithIndexClauseOrJOIN(
2316 $table, $use_index, $ignore_index, $join_conds ) . ')';
2319 $innerTable = reset( $table );
2320 $innerAlias = key( $table );
2321 $joinedTable = $this->tableNameWithAlias(
2323 is_string( $innerAlias ) ?
$innerAlias : $innerTable
2327 $joinedTable = $this->tableNameWithAlias( $table, $alias );
2330 // Is there a JOIN clause for this table?
2331 if ( isset( $join_conds[$alias] ) ) {
2332 list( $joinType, $conds ) = $join_conds[$alias];
2333 $tableClause = $joinType;
2334 $tableClause .= ' ' . $joinedTable;
2335 if ( isset( $use_index[$alias] ) ) { // has USE INDEX?
2336 $use = $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) );
2338 $tableClause .= ' ' . $use;
2341 if ( isset( $ignore_index[$alias] ) ) { // has IGNORE INDEX?
2342 $ignore = $this->ignoreIndexClause(
2343 implode( ',', (array)$ignore_index[$alias] ) );
2344 if ( $ignore != '' ) {
2345 $tableClause .= ' ' . $ignore;
2348 $on = $this->makeList( (array)$conds, self
::LIST_AND
);
2350 $tableClause .= ' ON (' . $on . ')';
2353 $retJOIN[] = $tableClause;
2354 } elseif ( isset( $use_index[$alias] ) ) {
2355 // Is there an INDEX clause for this table?
2356 $tableClause = $joinedTable;
2357 $tableClause .= ' ' . $this->useIndexClause(
2358 implode( ',', (array)$use_index[$alias] )
2361 $ret[] = $tableClause;
2362 } elseif ( isset( $ignore_index[$alias] ) ) {
2363 // Is there an INDEX clause for this table?
2364 $tableClause = $joinedTable;
2365 $tableClause .= ' ' . $this->ignoreIndexClause(
2366 implode( ',', (array)$ignore_index[$alias] )
2369 $ret[] = $tableClause;
2371 $tableClause = $joinedTable;
2373 $ret[] = $tableClause;
2377 // We can't separate explicit JOIN clauses with ',', use ' ' for those
2378 $implicitJoins = $ret ?
implode( ',', $ret ) : "";
2379 $explicitJoins = $retJOIN ?
implode( ' ', $retJOIN ) : "";
2381 // Compile our final table clause
2382 return implode( ' ', [ $implicitJoins, $explicitJoins ] );
2386 * Allows for index remapping in queries where this is not consistent across DBMS
2388 * @param string $index
2391 protected function indexName( $index ) {
2392 return isset( $this->indexAliases
[$index] )
2393 ?
$this->indexAliases
[$index]
2397 public function addQuotes( $s ) {
2398 if ( $s instanceof Blob
) {
2401 if ( $s === null ) {
2403 } elseif ( is_bool( $s ) ) {
2406 # This will also quote numeric values. This should be harmless,
2407 # and protects against weird problems that occur when they really
2408 # _are_ strings such as article titles and string->number->string
2409 # conversion is not 1:1.
2410 return "'" . $this->strencode( $s ) . "'";
2415 * Quotes an identifier using `backticks` or "double quotes" depending on the database type.
2416 * MySQL uses `backticks` while basically everything else uses double quotes.
2417 * Since MySQL is the odd one out here the double quotes are our generic
2418 * and we implement backticks in DatabaseMysqlBase.
2423 public function addIdentifierQuotes( $s ) {
2424 return '"' . str_replace( '"', '""', $s ) . '"';
2428 * Returns if the given identifier looks quoted or not according to
2429 * the database convention for quoting identifiers .
2431 * @note Do not use this to determine if untrusted input is safe.
2432 * A malicious user can trick this function.
2433 * @param string $name
2436 public function isQuotedIdentifier( $name ) {
2437 return $name[0] == '"' && substr( $name, -1, 1 ) == '"';
2442 * @param string $escapeChar
2445 protected function escapeLikeInternal( $s, $escapeChar = '`' ) {
2446 return str_replace( [ $escapeChar, '%', '_' ],
2447 [ "{$escapeChar}{$escapeChar}", "{$escapeChar}%", "{$escapeChar}_" ],
2451 public function buildLike() {
2452 $params = func_get_args();
2454 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
2455 $params = $params[0];
2460 // We use ` instead of \ as the default LIKE escape character, since addQuotes()
2461 // may escape backslashes, creating problems of double escaping. The `
2462 // character has good cross-DBMS compatibility, avoiding special operators
2463 // in MS SQL like ^ and %
2466 foreach ( $params as $value ) {
2467 if ( $value instanceof LikeMatch
) {
2468 $s .= $value->toString();
2470 $s .= $this->escapeLikeInternal( $value, $escapeChar );
2475 $this->addQuotes( $s ) . ' ESCAPE ' . $this->addQuotes( $escapeChar ) . ' ';
2478 public function anyChar() {
2479 return new LikeMatch( '_' );
2482 public function anyString() {
2483 return new LikeMatch( '%' );
2486 public function nextSequenceValue( $seqName ) {
2491 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
2492 * is only needed because a) MySQL must be as efficient as possible due to
2493 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2494 * which index to pick. Anyway, other databases might have different
2495 * indexes on a given table. So don't bother overriding this unless you're
2497 * @param string $index
2500 public function useIndexClause( $index ) {
2505 * IGNORE INDEX clause. Unlikely to be useful for anything but MySQL. This
2506 * is only needed because a) MySQL must be as efficient as possible due to
2507 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2508 * which index to pick. Anyway, other databases might have different
2509 * indexes on a given table. So don't bother overriding this unless you're
2511 * @param string $index
2514 public function ignoreIndexClause( $index ) {
2518 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__
) {
2519 if ( count( $rows ) == 0 ) {
2524 if ( !is_array( reset( $rows ) ) ) {
2529 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2530 $affectedRowCount = 0;
2531 foreach ( $rows as $row ) {
2532 // Delete rows which collide with this one
2533 $indexWhereClauses = [];
2534 foreach ( $uniqueIndexes as $index ) {
2535 $indexColumns = (array)$index;
2536 $indexRowValues = array_intersect_key( $row, array_flip( $indexColumns ) );
2537 if ( count( $indexRowValues ) != count( $indexColumns ) ) {
2538 throw new DBUnexpectedError(
2540 'New record does not provide all values for unique key (' .
2541 implode( ', ', $indexColumns ) . ')'
2543 } elseif ( in_array( null, $indexRowValues, true ) ) {
2544 throw new DBUnexpectedError(
2546 'New record has a null value for unique key (' .
2547 implode( ', ', $indexColumns ) . ')'
2550 $indexWhereClauses[] = $this->makeList( $indexRowValues, LIST_AND
);
2553 if ( $indexWhereClauses ) {
2554 $this->delete( $table, $this->makeList( $indexWhereClauses, LIST_OR
), $fname );
2555 $affectedRowCount +
= $this->affectedRows();
2558 // Now insert the row
2559 $this->insert( $table, $row, $fname );
2560 $affectedRowCount +
= $this->affectedRows();
2562 $this->endAtomic( $fname );
2563 $this->affectedRowCount
= $affectedRowCount;
2564 } catch ( Exception
$e ) {
2565 $this->cancelAtomic( $fname );
2571 * REPLACE query wrapper for MySQL and SQLite, which have a native REPLACE
2574 * @param string $table Table name
2575 * @param array|string $rows Row(s) to insert
2576 * @param string $fname Caller function name
2578 * @return ResultWrapper
2580 protected function nativeReplace( $table, $rows, $fname ) {
2581 $table = $this->tableName( $table );
2584 if ( !is_array( reset( $rows ) ) ) {
2588 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES ';
2591 foreach ( $rows as $row ) {
2598 $sql .= '(' . $this->makeList( $row ) . ')';
2601 return $this->query( $sql, $fname );
2604 public function upsert( $table, array $rows, array $uniqueIndexes, array $set,
2607 if ( !count( $rows ) ) {
2608 return true; // nothing to do
2611 if ( !is_array( reset( $rows ) ) ) {
2615 if ( count( $uniqueIndexes ) ) {
2616 $clauses = []; // list WHERE clauses that each identify a single row
2617 foreach ( $rows as $row ) {
2618 foreach ( $uniqueIndexes as $index ) {
2619 $index = is_array( $index ) ?
$index : [ $index ]; // columns
2620 $rowKey = []; // unique key to this row
2621 foreach ( $index as $column ) {
2622 $rowKey[$column] = $row[$column];
2624 $clauses[] = $this->makeList( $rowKey, self
::LIST_AND
);
2627 $where = [ $this->makeList( $clauses, self
::LIST_OR
) ];
2632 $affectedRowCount = 0;
2634 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2635 # Update any existing conflicting row(s)
2636 if ( $where !== false ) {
2637 $ok = $this->update( $table, $set, $where, $fname );
2638 $affectedRowCount +
= $this->affectedRows();
2642 # Now insert any non-conflicting row(s)
2643 $ok = $this->insert( $table, $rows, $fname, [ 'IGNORE' ] ) && $ok;
2644 $affectedRowCount +
= $this->affectedRows();
2645 $this->endAtomic( $fname );
2646 $this->affectedRowCount
= $affectedRowCount;
2647 } catch ( Exception
$e ) {
2648 $this->cancelAtomic( $fname );
2655 public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
2659 throw new DBUnexpectedError( $this, __METHOD__
. ' called with empty $conds' );
2662 $delTable = $this->tableName( $delTable );
2663 $joinTable = $this->tableName( $joinTable );
2664 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
2665 if ( $conds != '*' ) {
2666 $sql .= 'WHERE ' . $this->makeList( $conds, self
::LIST_AND
);
2670 $this->query( $sql, $fname );
2673 public function textFieldSize( $table, $field ) {
2674 $table = $this->tableName( $table );
2675 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
2676 $res = $this->query( $sql, __METHOD__
);
2677 $row = $this->fetchObject( $res );
2681 if ( preg_match( '/\((.*)\)/', $row->Type
, $m ) ) {
2690 public function delete( $table, $conds, $fname = __METHOD__
) {
2692 throw new DBUnexpectedError( $this, __METHOD__
. ' called with no conditions' );
2695 $table = $this->tableName( $table );
2696 $sql = "DELETE FROM $table";
2698 if ( $conds != '*' ) {
2699 if ( is_array( $conds ) ) {
2700 $conds = $this->makeList( $conds, self
::LIST_AND
);
2702 $sql .= ' WHERE ' . $conds;
2705 return $this->query( $sql, $fname );
2708 final public function insertSelect(
2709 $destTable, $srcTable, $varMap, $conds,
2710 $fname = __METHOD__
, $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2712 static $hints = [ 'NO_AUTO_COLUMNS' ];
2714 $insertOptions = (array)$insertOptions;
2715 $selectOptions = (array)$selectOptions;
2717 if ( $this->cliMode
&& $this->isInsertSelectSafe( $insertOptions, $selectOptions ) ) {
2718 // For massive migrations with downtime, we don't want to select everything
2719 // into memory and OOM, so do all this native on the server side if possible.
2720 return $this->nativeInsertSelect(
2726 array_diff( $insertOptions, $hints ),
2732 return $this->nonNativeInsertSelect(
2738 array_diff( $insertOptions, $hints ),
2745 * @param array $insertOptions INSERT options
2746 * @param array $selectOptions SELECT options
2747 * @return bool Whether an INSERT SELECT with these options will be replication safe
2750 protected function isInsertSelectSafe( array $insertOptions, array $selectOptions ) {
2755 * Implementation of insertSelect() based on select() and insert()
2757 * @see IDatabase::insertSelect()
2759 * @param string $destTable
2760 * @param string|array $srcTable
2761 * @param array $varMap
2762 * @param array $conds
2763 * @param string $fname
2764 * @param array $insertOptions
2765 * @param array $selectOptions
2766 * @param array $selectJoinConds
2769 protected function nonNativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
2770 $fname = __METHOD__
,
2771 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2773 // For web requests, do a locking SELECT and then INSERT. This puts the SELECT burden
2774 // on only the master (without needing row-based-replication). It also makes it easy to
2775 // know how big the INSERT is going to be.
2777 foreach ( $varMap as $dstColumn => $sourceColumnOrSql ) {
2778 $fields[] = $this->fieldNameWithAlias( $sourceColumnOrSql, $dstColumn );
2780 $selectOptions[] = 'FOR UPDATE';
2781 $res = $this->select(
2782 $srcTable, implode( ',', $fields ), $conds, $fname, $selectOptions, $selectJoinConds
2789 $affectedRowCount = 0;
2790 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2793 foreach ( $res as $row ) {
2794 $rows[] = (array)$row;
2796 // Avoid inserts that are too huge
2797 if ( count( $rows ) >= $this->nonNativeInsertSelectBatchSize
) {
2798 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
2802 $affectedRowCount +
= $this->affectedRows();
2806 if ( $rows && $ok ) {
2807 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
2809 $affectedRowCount +
= $this->affectedRows();
2813 $this->endAtomic( $fname );
2814 $this->affectedRowCount
= $affectedRowCount;
2816 $this->cancelAtomic( $fname );
2819 } catch ( Exception
$e ) {
2820 $this->cancelAtomic( $fname );
2826 * Native server-side implementation of insertSelect() for situations where
2827 * we don't want to select everything into memory
2829 * @see IDatabase::insertSelect()
2830 * @param string $destTable
2831 * @param string|array $srcTable
2832 * @param array $varMap
2833 * @param array $conds
2834 * @param string $fname
2835 * @param array $insertOptions
2836 * @param array $selectOptions
2837 * @param array $selectJoinConds
2840 protected function nativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
2841 $fname = __METHOD__
,
2842 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
2844 $destTable = $this->tableName( $destTable );
2846 if ( !is_array( $insertOptions ) ) {
2847 $insertOptions = [ $insertOptions ];
2850 $insertOptions = $this->makeInsertOptions( $insertOptions );
2852 $selectSql = $this->selectSQLText(
2854 array_values( $varMap ),
2861 $sql = "INSERT $insertOptions" .
2862 " INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ') ' .
2865 return $this->query( $sql, $fname );
2869 * Construct a LIMIT query with optional offset. This is used for query
2870 * pages. The SQL should be adjusted so that only the first $limit rows
2871 * are returned. If $offset is provided as well, then the first $offset
2872 * rows should be discarded, and the next $limit rows should be returned.
2873 * If the result of the query is not ordered, then the rows to be returned
2874 * are theoretically arbitrary.
2876 * $sql is expected to be a SELECT, if that makes a difference.
2878 * The version provided by default works in MySQL and SQLite. It will very
2879 * likely need to be overridden for most other DBMSes.
2881 * @param string $sql SQL query we will append the limit too
2882 * @param int $limit The SQL limit
2883 * @param int|bool $offset The SQL offset (default false)
2884 * @throws DBUnexpectedError
2887 public function limitResult( $sql, $limit, $offset = false ) {
2888 if ( !is_numeric( $limit ) ) {
2889 throw new DBUnexpectedError( $this,
2890 "Invalid non-numeric limit passed to limitResult()\n" );
2893 return "$sql LIMIT "
2894 . ( ( is_numeric( $offset ) && $offset != 0 ) ?
"{$offset}," : "" )
2898 public function unionSupportsOrderAndLimit() {
2899 return true; // True for almost every DB supported
2902 public function unionQueries( $sqls, $all ) {
2903 $glue = $all ?
') UNION ALL (' : ') UNION (';
2905 return '(' . implode( $glue, $sqls ) . ')';
2908 public function unionConditionPermutations(
2909 $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__
,
2910 $options = [], $join_conds = []
2912 // First, build the Cartesian product of $permute_conds
2914 foreach ( $permute_conds as $field => $values ) {
2916 // Skip empty $values
2919 $values = array_unique( $values ); // For sanity
2921 foreach ( $conds as $cond ) {
2922 foreach ( $values as $value ) {
2923 $cond[$field] = $value;
2924 $newConds[] = $cond; // Arrays are by-value, not by-reference, so this works
2930 $extra_conds = $extra_conds === '' ?
[] : (array)$extra_conds;
2932 // If there's just one condition and no subordering, hand off to
2933 // selectSQLText directly.
2934 if ( count( $conds ) === 1 &&
2935 ( !isset( $options['INNER ORDER BY'] ) ||
!$this->unionSupportsOrderAndLimit() )
2937 return $this->selectSQLText(
2938 $table, $vars, $conds[0] +
$extra_conds, $fname, $options, $join_conds
2942 // Otherwise, we need to pull out the order and limit to apply after
2943 // the union. Then build the SQL queries for each set of conditions in
2944 // $conds. Then union them together (using UNION ALL, because the
2945 // product *should* already be distinct).
2946 $orderBy = $this->makeOrderBy( $options );
2947 $limit = isset( $options['LIMIT'] ) ?
$options['LIMIT'] : null;
2948 $offset = isset( $options['OFFSET'] ) ?
$options['OFFSET'] : false;
2949 $all = empty( $options['NOTALL'] ) && !in_array( 'NOTALL', $options );
2950 if ( !$this->unionSupportsOrderAndLimit() ) {
2951 unset( $options['ORDER BY'], $options['LIMIT'], $options['OFFSET'] );
2953 if ( array_key_exists( 'INNER ORDER BY', $options ) ) {
2954 $options['ORDER BY'] = $options['INNER ORDER BY'];
2956 if ( $limit !== null && is_numeric( $offset ) && $offset != 0 ) {
2957 // We need to increase the limit by the offset rather than
2958 // using the offset directly, otherwise it'll skip incorrectly
2959 // in the subqueries.
2960 $options['LIMIT'] = $limit +
$offset;
2961 unset( $options['OFFSET'] );
2966 foreach ( $conds as $cond ) {
2967 $sqls[] = $this->selectSQLText(
2968 $table, $vars, $cond +
$extra_conds, $fname, $options, $join_conds
2971 $sql = $this->unionQueries( $sqls, $all ) . $orderBy;
2972 if ( $limit !== null ) {
2973 $sql = $this->limitResult( $sql, $limit, $offset );
2979 public function conditional( $cond, $trueVal, $falseVal ) {
2980 if ( is_array( $cond ) ) {
2981 $cond = $this->makeList( $cond, self
::LIST_AND
);
2984 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
2987 public function strreplace( $orig, $old, $new ) {
2988 return "REPLACE({$orig}, {$old}, {$new})";
2991 public function getServerUptime() {
2995 public function wasDeadlock() {
2999 public function wasLockTimeout() {
3003 public function wasConnectionLoss() {
3004 return $this->wasConnectionError( $this->lastErrno() );
3007 public function wasReadOnlyError() {
3011 public function wasErrorReissuable() {
3013 $this->wasDeadlock() ||
3014 $this->wasLockTimeout() ||
3015 $this->wasConnectionLoss()
3020 * Do not use this method outside of Database/DBError classes
3022 * @param int|string $errno
3023 * @return bool Whether the given query error was a connection drop
3025 public function wasConnectionError( $errno ) {
3029 public function deadlockLoop() {
3030 $args = func_get_args();
3031 $function = array_shift( $args );
3032 $tries = self
::DEADLOCK_TRIES
;
3034 $this->begin( __METHOD__
);
3037 /** @var Exception $e */
3041 $retVal = call_user_func_array( $function, $args );
3043 } catch ( DBQueryError
$e ) {
3044 if ( $this->wasDeadlock() ) {
3045 // Retry after a randomized delay
3046 usleep( mt_rand( self
::DEADLOCK_DELAY_MIN
, self
::DEADLOCK_DELAY_MAX
) );
3048 // Throw the error back up
3052 } while ( --$tries > 0 );
3054 if ( $tries <= 0 ) {
3055 // Too many deadlocks; give up
3056 $this->rollback( __METHOD__
);
3059 $this->commit( __METHOD__
);
3065 public function masterPosWait( DBMasterPos
$pos, $timeout ) {
3066 # Real waits are implemented in the subclass.
3070 public function getReplicaPos() {
3075 public function getMasterPos() {
3080 public function serverIsReadOnly() {
3084 final public function onTransactionResolution( callable
$callback, $fname = __METHOD__
) {
3085 if ( !$this->trxLevel
) {
3086 throw new DBUnexpectedError( $this, "No transaction is active." );
3088 $this->trxEndCallbacks
[] = [ $callback, $fname ];
3091 final public function onTransactionIdle( callable
$callback, $fname = __METHOD__
) {
3092 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3093 // Start an implicit transaction similar to how query() does
3094 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3095 $this->trxAutomatic
= true;
3098 $this->trxIdleCallbacks
[] = [ $callback, $fname ];
3099 if ( !$this->trxLevel
) {
3100 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_IDLE
);
3104 final public function onTransactionPreCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3105 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3106 // Start an implicit transaction similar to how query() does
3107 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3108 $this->trxAutomatic
= true;
3111 if ( $this->trxLevel
) {
3112 $this->trxPreCommitCallbacks
[] = [ $callback, $fname ];
3114 // No transaction is active nor will start implicitly, so make one for this callback
3115 $this->startAtomic( __METHOD__
, self
::ATOMIC_CANCELABLE
);
3117 call_user_func( $callback );
3118 $this->endAtomic( __METHOD__
);
3119 } catch ( Exception
$e ) {
3120 $this->cancelAtomic( __METHOD__
);
3126 final public function setTransactionListener( $name, callable
$callback = null ) {
3128 $this->trxRecurringCallbacks
[$name] = $callback;
3130 unset( $this->trxRecurringCallbacks
[$name] );
3135 * Whether to disable running of post-COMMIT/ROLLBACK callbacks
3137 * This method should not be used outside of Database/LoadBalancer
3139 * @param bool $suppress
3142 final public function setTrxEndCallbackSuppression( $suppress ) {
3143 $this->trxEndCallbacksSuppressed
= $suppress;
3147 * Actually run and consume any "on transaction idle/resolution" callbacks.
3149 * This method should not be used outside of Database/LoadBalancer
3151 * @param int $trigger IDatabase::TRIGGER_* constant
3155 public function runOnTransactionIdleCallbacks( $trigger ) {
3156 if ( $this->trxEndCallbacksSuppressed
) {
3160 $autoTrx = $this->getFlag( self
::DBO_TRX
); // automatic begin() enabled?
3161 /** @var Exception $e */
3162 $e = null; // first exception
3163 do { // callbacks may add callbacks :)
3164 $callbacks = array_merge(
3165 $this->trxIdleCallbacks
,
3166 $this->trxEndCallbacks
// include "transaction resolution" callbacks
3168 $this->trxIdleCallbacks
= []; // consumed (and recursion guard)
3169 $this->trxEndCallbacks
= []; // consumed (recursion guard)
3170 foreach ( $callbacks as $callback ) {
3172 list( $phpCallback ) = $callback;
3173 $this->clearFlag( self
::DBO_TRX
); // make each query its own transaction
3174 call_user_func_array( $phpCallback, [ $trigger ] );
3176 $this->setFlag( self
::DBO_TRX
); // restore automatic begin()
3178 $this->clearFlag( self
::DBO_TRX
); // restore auto-commit
3180 } catch ( Exception
$ex ) {
3181 call_user_func( $this->errorLogger
, $ex );
3183 // Some callbacks may use startAtomic/endAtomic, so make sure
3184 // their transactions are ended so other callbacks don't fail
3185 if ( $this->trxLevel() ) {
3186 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
3190 } while ( count( $this->trxIdleCallbacks
) );
3192 if ( $e instanceof Exception
) {
3193 throw $e; // re-throw any first exception
3198 * Actually run and consume any "on transaction pre-commit" callbacks.
3200 * This method should not be used outside of Database/LoadBalancer
3205 public function runOnTransactionPreCommitCallbacks() {
3206 $e = null; // first exception
3207 do { // callbacks may add callbacks :)
3208 $callbacks = $this->trxPreCommitCallbacks
;
3209 $this->trxPreCommitCallbacks
= []; // consumed (and recursion guard)
3210 foreach ( $callbacks as $callback ) {
3212 list( $phpCallback ) = $callback;
3213 call_user_func( $phpCallback );
3214 } catch ( Exception
$ex ) {
3215 call_user_func( $this->errorLogger
, $ex );
3219 } while ( count( $this->trxPreCommitCallbacks
) );
3221 if ( $e instanceof Exception
) {
3222 throw $e; // re-throw any first exception
3227 * Actually run any "transaction listener" callbacks.
3229 * This method should not be used outside of Database/LoadBalancer
3231 * @param int $trigger IDatabase::TRIGGER_* constant
3235 public function runTransactionListenerCallbacks( $trigger ) {
3236 if ( $this->trxEndCallbacksSuppressed
) {
3240 /** @var Exception $e */
3241 $e = null; // first exception
3243 foreach ( $this->trxRecurringCallbacks
as $phpCallback ) {
3245 $phpCallback( $trigger, $this );
3246 } catch ( Exception
$ex ) {
3247 call_user_func( $this->errorLogger
, $ex );
3252 if ( $e instanceof Exception
) {
3253 throw $e; // re-throw any first exception
3258 * Create a savepoint
3260 * This is used internally to implement atomic sections. It should not be
3264 * @param string $identifier Identifier for the savepoint
3265 * @param string $fname Calling function name
3267 protected function doSavepoint( $identifier, $fname ) {
3268 $this->query( 'SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3272 * Release a savepoint
3274 * This is used internally to implement atomic sections. It should not be
3278 * @param string $identifier Identifier for the savepoint
3279 * @param string $fname Calling function name
3281 protected function doReleaseSavepoint( $identifier, $fname ) {
3282 $this->query( 'RELEASE SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3286 * Rollback to a savepoint
3288 * This is used internally to implement atomic sections. It should not be
3292 * @param string $identifier Identifier for the savepoint
3293 * @param string $fname Calling function name
3295 protected function doRollbackToSavepoint( $identifier, $fname ) {
3296 $this->query( 'ROLLBACK TO SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3299 final public function startAtomic(
3300 $fname = __METHOD__
, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3302 $savepointId = $cancelable === self
::ATOMIC_CANCELABLE ?
'n/a' : null;
3303 if ( !$this->trxLevel
) {
3304 $this->begin( $fname, self
::TRANSACTION_INTERNAL
);
3305 // If DBO_TRX is set, a series of startAtomic/endAtomic pairs will result
3306 // in all changes being in one transaction to keep requests transactional.
3307 if ( !$this->getFlag( self
::DBO_TRX
) ) {
3308 $this->trxAutomaticAtomic
= true;
3310 } elseif ( $cancelable === self
::ATOMIC_CANCELABLE
) {
3311 $savepointId = 'wikimedia_rdbms_atomic' . ++
$this->trxAtomicCounter
;
3312 if ( strlen( $savepointId ) > 30 ) { // 30 == Oracle's identifier length limit (pre 12c)
3313 $this->queryLogger
->warning(
3314 'There have been an excessively large number of atomic sections in a transaction'
3315 . " started by $this->trxFname, reusing IDs (at $fname)",
3316 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
3318 $this->trxAtomicCounter
= 0;
3319 $savepointId = 'wikimedia_rdbms_atomic' . ++
$this->trxAtomicCounter
;
3321 $this->doSavepoint( $savepointId, $fname );
3324 $this->trxAtomicLevels
[] = [ $fname, $savepointId ];
3327 final public function endAtomic( $fname = __METHOD__
) {
3328 if ( !$this->trxLevel
) {
3329 throw new DBUnexpectedError( $this, "No atomic transaction is open (got $fname)." );
3332 list( $savedFname, $savepointId ) = $this->trxAtomicLevels
3333 ?
array_pop( $this->trxAtomicLevels
) : [ null, null ];
3334 if ( $savedFname !== $fname ) {
3335 throw new DBUnexpectedError( $this, "Invalid atomic section ended (got $fname)." );
3338 if ( !$this->trxAtomicLevels
&& $this->trxAutomaticAtomic
) {
3339 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3340 } elseif ( $savepointId && $savepointId !== 'n/a' ) {
3341 $this->doReleaseSavepoint( $savepointId, $fname );
3345 final public function cancelAtomic( $fname = __METHOD__
) {
3346 if ( !$this->trxLevel
) {
3347 throw new DBUnexpectedError( $this, "No atomic transaction is open (got $fname)." );
3350 list( $savedFname, $savepointId ) = $this->trxAtomicLevels
3351 ?
array_pop( $this->trxAtomicLevels
) : [ null, null ];
3352 if ( $savedFname !== $fname ) {
3353 throw new DBUnexpectedError( $this, "Invalid atomic section ended (got $fname)." );
3355 if ( !$savepointId ) {
3356 throw new DBUnexpectedError( $this, "Uncancelable atomic section canceled (got $fname)." );
3359 if ( !$this->trxAtomicLevels
&& $this->trxAutomaticAtomic
) {
3360 $this->rollback( $fname, self
::FLUSHING_INTERNAL
);
3361 } elseif ( $savepointId !== 'n/a' ) {
3362 $this->doRollbackToSavepoint( $savepointId, $fname );
3365 $this->affectedRowCount
= 0; // for the sake of consistency
3368 final public function doAtomicSection( $fname, callable
$callback ) {
3369 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
3371 $res = call_user_func_array( $callback, [ $this, $fname ] );
3372 } catch ( Exception
$e ) {
3373 $this->cancelAtomic( $fname );
3376 $this->endAtomic( $fname );
3381 final public function begin( $fname = __METHOD__
, $mode = self
::TRANSACTION_EXPLICIT
) {
3382 // Protect against mismatched atomic section, transaction nesting, and snapshot loss
3383 if ( $this->trxLevel
) {
3384 if ( $this->trxAtomicLevels
) {
3385 $levels = array_reduce( $this->trxAtomicLevels
, function ( $accum, $v ) {
3386 return $accum === null ?
$v[0] : "$accum, " . $v[0];
3388 $msg = "$fname: Got explicit BEGIN while atomic section(s) $levels are open.";
3389 throw new DBUnexpectedError( $this, $msg );
3390 } elseif ( !$this->trxAutomatic
) {
3391 $msg = "$fname: Explicit transaction already active (from {$this->trxFname}).";
3392 throw new DBUnexpectedError( $this, $msg );
3394 $msg = "$fname: Implicit transaction already active (from {$this->trxFname}).";
3395 throw new DBUnexpectedError( $this, $msg );
3397 } elseif ( $this->getFlag( self
::DBO_TRX
) && $mode !== self
::TRANSACTION_INTERNAL
) {
3398 $msg = "$fname: Implicit transaction expected (DBO_TRX set).";
3399 throw new DBUnexpectedError( $this, $msg );
3402 // Avoid fatals if close() was called
3403 $this->assertOpen();
3405 $this->doBegin( $fname );
3406 $this->trxAtomicCounter
= 0;
3407 $this->trxTimestamp
= microtime( true );
3408 $this->trxFname
= $fname;
3409 $this->trxDoneWrites
= false;
3410 $this->trxAutomaticAtomic
= false;
3411 $this->trxAtomicLevels
= [];
3412 $this->trxShortId
= sprintf( '%06x', mt_rand( 0, 0xffffff ) );
3413 $this->trxWriteDuration
= 0.0;
3414 $this->trxWriteQueryCount
= 0;
3415 $this->trxWriteAffectedRows
= 0;
3416 $this->trxWriteAdjDuration
= 0.0;
3417 $this->trxWriteAdjQueryCount
= 0;
3418 $this->trxWriteCallers
= [];
3419 // First SELECT after BEGIN will establish the snapshot in REPEATABLE-READ.
3420 // Get an estimate of the replication lag before any such queries.
3421 $this->trxReplicaLag
= $this->getApproximateLagStatus()['lag'];
3422 // T147697: make explicitTrxActive() return true until begin() finishes. This way, no
3423 // caller will think its OK to muck around with the transaction just because startAtomic()
3424 // has not yet completed (e.g. setting trxAtomicLevels).
3425 $this->trxAutomatic
= ( $mode === self
::TRANSACTION_INTERNAL
);
3429 * Issues the BEGIN command to the database server.
3431 * @see Database::begin()
3432 * @param string $fname
3434 protected function doBegin( $fname ) {
3435 $this->query( 'BEGIN', $fname );
3436 $this->trxLevel
= 1;
3439 final public function commit( $fname = __METHOD__
, $flush = '' ) {
3440 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3441 // There are still atomic sections open. This cannot be ignored
3442 $levels = array_reduce( $this->trxAtomicLevels
, function ( $accum, $v ) {
3443 return $accum === null ?
$v[0] : "$accum, " . $v[0];
3445 throw new DBUnexpectedError(
3447 "$fname: Got COMMIT while atomic sections $levels are still open."
3451 if ( $flush === self
::FLUSHING_INTERNAL ||
$flush === self
::FLUSHING_ALL_PEERS
) {
3452 if ( !$this->trxLevel
) {
3453 return; // nothing to do
3454 } elseif ( !$this->trxAutomatic
) {
3455 throw new DBUnexpectedError(
3457 "$fname: Flushing an explicit transaction, getting out of sync."
3461 if ( !$this->trxLevel
) {
3462 $this->queryLogger
->error(
3463 "$fname: No transaction to commit, something got out of sync." );
3464 return; // nothing to do
3465 } elseif ( $this->trxAutomatic
) {
3466 throw new DBUnexpectedError(
3468 "$fname: Expected mass commit of all peer transactions (DBO_TRX set)."
3473 // Avoid fatals if close() was called
3474 $this->assertOpen();
3476 $this->runOnTransactionPreCommitCallbacks();
3477 $writeTime = $this->pendingWriteQueryDuration( self
::ESTIMATE_DB_APPLY
);
3478 $this->doCommit( $fname );
3479 if ( $this->trxDoneWrites
) {
3480 $this->lastWriteTime
= microtime( true );
3481 $this->trxProfiler
->transactionWritingOut(
3486 $this->trxWriteAffectedRows
3490 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_COMMIT
);
3491 $this->runTransactionListenerCallbacks( self
::TRIGGER_COMMIT
);
3495 * Issues the COMMIT command to the database server.
3497 * @see Database::commit()
3498 * @param string $fname
3500 protected function doCommit( $fname ) {
3501 if ( $this->trxLevel
) {
3502 $this->query( 'COMMIT', $fname );
3503 $this->trxLevel
= 0;
3507 final public function rollback( $fname = __METHOD__
, $flush = '' ) {
3508 $trxActive = $this->trxLevel
;
3510 if ( $flush !== self
::FLUSHING_INTERNAL
&& $flush !== self
::FLUSHING_ALL_PEERS
) {
3511 if ( $this->getFlag( self
::DBO_TRX
) ) {
3512 throw new DBUnexpectedError(
3514 "$fname: Expected mass rollback of all peer transactions (DBO_TRX set)."
3520 // Avoid fatals if close() was called
3521 $this->assertOpen();
3523 $this->doRollback( $fname );
3524 $this->trxAtomicLevels
= [];
3525 if ( $this->trxDoneWrites
) {
3526 $this->trxProfiler
->transactionWritingOut(
3534 // Clear any commit-dependant callbacks. They might even be present
3535 // only due to transaction rounds, with no SQL transaction being active
3536 $this->trxIdleCallbacks
= [];
3537 $this->trxPreCommitCallbacks
= [];
3541 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
3542 } catch ( Exception
$e ) {
3543 // already logged; finish and let LoadBalancer move on during mass-rollback
3546 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
3547 } catch ( Exception
$e ) {
3548 // already logged; let LoadBalancer move on during mass-rollback
3551 $this->affectedRowCount
= 0; // for the sake of consistency
3556 * Issues the ROLLBACK command to the database server.
3558 * @see Database::rollback()
3559 * @param string $fname
3561 protected function doRollback( $fname ) {
3562 if ( $this->trxLevel
) {
3563 # Disconnects cause rollback anyway, so ignore those errors
3564 $ignoreErrors = true;
3565 $this->query( 'ROLLBACK', $fname, $ignoreErrors );
3566 $this->trxLevel
= 0;
3570 public function flushSnapshot( $fname = __METHOD__
) {
3571 if ( $this->writesOrCallbacksPending() ||
$this->explicitTrxActive() ) {
3572 // This only flushes transactions to clear snapshots, not to write data
3573 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
3574 throw new DBUnexpectedError(
3576 "$fname: Cannot flush snapshot because writes are pending ($fnames)."
3580 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3583 public function explicitTrxActive() {
3584 return $this->trxLevel
&& ( $this->trxAtomicLevels ||
!$this->trxAutomatic
);
3587 public function duplicateTableStructure(
3588 $oldName, $newName, $temporary = false, $fname = __METHOD__
3590 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
3593 public function listTables( $prefix = null, $fname = __METHOD__
) {
3594 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
3597 public function listViews( $prefix = null, $fname = __METHOD__
) {
3598 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
3601 public function timestamp( $ts = 0 ) {
3602 $t = new ConvertibleTimestamp( $ts );
3603 // Let errors bubble up to avoid putting garbage in the DB
3604 return $t->getTimestamp( TS_MW
);
3607 public function timestampOrNull( $ts = null ) {
3608 if ( is_null( $ts ) ) {
3611 return $this->timestamp( $ts );
3615 public function affectedRows() {
3616 return ( $this->affectedRowCount
=== null )
3617 ?
$this->fetchAffectedRowCount() // default to driver value
3618 : $this->affectedRowCount
;
3622 * @return int Number of retrieved rows according to the driver
3624 abstract protected function fetchAffectedRowCount();
3627 * Take the result from a query, and wrap it in a ResultWrapper if
3628 * necessary. Boolean values are passed through as is, to indicate success
3629 * of write queries or failure.
3631 * Once upon a time, Database::query() returned a bare MySQL result
3632 * resource, and it was necessary to call this function to convert it to
3633 * a wrapper. Nowadays, raw database objects are never exposed to external
3634 * callers, so this is unnecessary in external code.
3636 * @param bool|ResultWrapper|resource|object $result
3637 * @return bool|ResultWrapper
3639 protected function resultObject( $result ) {
3642 } elseif ( $result instanceof ResultWrapper
) {
3644 } elseif ( $result === true ) {
3645 // Successful write query
3648 return new ResultWrapper( $this, $result );
3652 public function ping( &$rtt = null ) {
3653 // Avoid hitting the server if it was hit recently
3654 if ( $this->isOpen() && ( microtime( true ) - $this->lastPing
) < self
::PING_TTL
) {
3655 if ( !func_num_args() ||
$this->rttEstimate
> 0 ) {
3656 $rtt = $this->rttEstimate
;
3657 return true; // don't care about $rtt
3661 // This will reconnect if possible or return false if not
3662 $this->clearFlag( self
::DBO_TRX
, self
::REMEMBER_PRIOR
);
3663 $ok = ( $this->query( self
::PING_QUERY
, __METHOD__
, true ) !== false );
3664 $this->restoreFlags( self
::RESTORE_PRIOR
);
3667 $rtt = $this->rttEstimate
;
3674 * Close any existing (dead) database connection and open a new connection
3676 * @param string $fname
3677 * @return bool True if new connection is opened successfully, false if error
3679 protected function replaceLostConnection( $fname ) {
3680 $this->closeConnection();
3681 $this->opened
= false;
3682 $this->conn
= false;
3684 $this->open( $this->server
, $this->user
, $this->password
, $this->dbName
);
3685 $this->lastPing
= microtime( true );
3688 $this->connLogger
->warning(
3689 $fname . ': lost connection to {dbserver}; reconnected',
3691 'dbserver' => $this->getServer(),
3692 'trace' => ( new RuntimeException() )->getTraceAsString()
3695 } catch ( DBConnectionError
$e ) {
3698 $this->connLogger
->error(
3699 $fname . ': lost connection to {dbserver} permanently',
3700 [ 'dbserver' => $this->getServer() ]
3704 $this->handleSessionLoss();
3709 public function getSessionLagStatus() {
3710 return $this->getTransactionLagStatus() ?
: $this->getApproximateLagStatus();
3714 * Get the replica DB lag when the current transaction started
3716 * This is useful when transactions might use snapshot isolation
3717 * (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data
3718 * is this lag plus transaction duration. If they don't, it is still
3719 * safe to be pessimistic. This returns null if there is no transaction.
3721 * @return array|null ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)
3724 final protected function getTransactionLagStatus() {
3725 return $this->trxLevel
3726 ?
[ 'lag' => $this->trxReplicaLag
, 'since' => $this->trxTimestamp() ]
3731 * Get a replica DB lag estimate for this server
3733 * @return array ('lag': seconds or false on error, 'since': UNIX timestamp of estimate)
3736 protected function getApproximateLagStatus() {
3738 'lag' => $this->getLBInfo( 'replica' ) ?
$this->getLag() : 0,
3739 'since' => microtime( true )
3744 * Merge the result of getSessionLagStatus() for several DBs
3745 * using the most pessimistic values to estimate the lag of
3746 * any data derived from them in combination
3748 * This is information is useful for caching modules
3750 * @see WANObjectCache::set()
3751 * @see WANObjectCache::getWithSetCallback()
3753 * @param IDatabase $db1
3754 * @param IDatabase $db2 [optional]
3755 * @return array Map of values:
3756 * - lag: highest lag of any of the DBs or false on error (e.g. replication stopped)
3757 * - since: oldest UNIX timestamp of any of the DB lag estimates
3758 * - pending: whether any of the DBs have uncommitted changes
3762 public static function getCacheSetOptions( IDatabase
$db1, IDatabase
$db2 = null ) {
3763 $res = [ 'lag' => 0, 'since' => INF
, 'pending' => false ];
3764 foreach ( func_get_args() as $db ) {
3765 /** @var IDatabase $db */
3766 $status = $db->getSessionLagStatus();
3767 if ( $status['lag'] === false ) {
3768 $res['lag'] = false;
3769 } elseif ( $res['lag'] !== false ) {
3770 $res['lag'] = max( $res['lag'], $status['lag'] );
3772 $res['since'] = min( $res['since'], $status['since'] );
3773 $res['pending'] = $res['pending'] ?
: $db->writesPending();
3779 public function getLag() {
3783 public function maxListLen() {
3787 public function encodeBlob( $b ) {
3791 public function decodeBlob( $b ) {
3792 if ( $b instanceof Blob
) {
3798 public function setSessionOptions( array $options ) {
3801 public function sourceFile(
3803 callable
$lineCallback = null,
3804 callable
$resultCallback = null,
3806 callable
$inputCallback = null
3808 Wikimedia\
suppressWarnings();
3809 $fp = fopen( $filename, 'r' );
3810 Wikimedia\restoreWarnings
();
3812 if ( false === $fp ) {
3813 throw new RuntimeException( "Could not open \"{$filename}\".\n" );
3817 $fname = __METHOD__
. "( $filename )";
3821 $error = $this->sourceStream(
3822 $fp, $lineCallback, $resultCallback, $fname, $inputCallback );
3823 } catch ( Exception
$e ) {
3833 public function setSchemaVars( $vars ) {
3834 $this->schemaVars
= $vars;
3837 public function sourceStream(
3839 callable
$lineCallback = null,
3840 callable
$resultCallback = null,
3841 $fname = __METHOD__
,
3842 callable
$inputCallback = null
3844 $delimiterReset = new ScopedCallback(
3845 function ( $delimiter ) {
3846 $this->delimiter
= $delimiter;
3848 [ $this->delimiter
]
3852 while ( !feof( $fp ) ) {
3853 if ( $lineCallback ) {
3854 call_user_func( $lineCallback );
3857 $line = trim( fgets( $fp ) );
3859 if ( $line == '' ) {
3863 if ( '-' == $line[0] && '-' == $line[1] ) {
3871 $done = $this->streamStatementEnd( $cmd, $line );
3875 if ( $done ||
feof( $fp ) ) {
3876 $cmd = $this->replaceVars( $cmd );
3878 if ( $inputCallback ) {
3879 $callbackResult = call_user_func( $inputCallback, $cmd );
3881 if ( is_string( $callbackResult ) ||
!$callbackResult ) {
3882 $cmd = $callbackResult;
3887 $res = $this->query( $cmd, $fname );
3889 if ( $resultCallback ) {
3890 call_user_func( $resultCallback, $res, $this );
3893 if ( false === $res ) {
3894 $err = $this->lastError();
3896 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
3903 ScopedCallback
::consume( $delimiterReset );
3908 * Called by sourceStream() to check if we've reached a statement end
3910 * @param string &$sql SQL assembled so far
3911 * @param string &$newLine New line about to be added to $sql
3912 * @return bool Whether $newLine contains end of the statement
3914 public function streamStatementEnd( &$sql, &$newLine ) {
3915 if ( $this->delimiter
) {
3917 $newLine = preg_replace(
3918 '/' . preg_quote( $this->delimiter
, '/' ) . '$/', '', $newLine );
3919 if ( $newLine != $prev ) {
3928 * Database independent variable replacement. Replaces a set of variables
3929 * in an SQL statement with their contents as given by $this->getSchemaVars().
3931 * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables.
3933 * - '{$var}' should be used for text and is passed through the database's
3935 * - `{$var}` should be used for identifiers (e.g. table and database names).
3936 * It is passed through the database's addIdentifierQuotes method which
3937 * can be overridden if the database uses something other than backticks.
3938 * - / *_* / or / *$wgDBprefix* / passes the name that follows through the
3939 * database's tableName method.
3940 * - / *i* / passes the name that follows through the database's indexName method.
3941 * - In all other cases, / *$var* / is left unencoded. Except for table options,
3942 * its use should be avoided. In 1.24 and older, string encoding was applied.
3944 * @param string $ins SQL statement to replace variables in
3945 * @return string The new SQL statement with variables replaced
3947 protected function replaceVars( $ins ) {
3948 $vars = $this->getSchemaVars();
3949 return preg_replace_callback(
3951 /\* (\$wgDBprefix|[_i]) \*/ (\w*) | # 1-2. tableName, indexName
3952 \'\{\$ (\w+) }\' | # 3. addQuotes
3953 `\{\$ (\w+) }` | # 4. addIdentifierQuotes
3954 /\*\$ (\w+) \*/ # 5. leave unencoded
3956 function ( $m ) use ( $vars ) {
3957 // Note: Because of <https://bugs.php.net/bug.php?id=51881>,
3958 // check for both nonexistent keys *and* the empty string.
3959 if ( isset( $m[1] ) && $m[1] !== '' ) {
3960 if ( $m[1] === 'i' ) {
3961 return $this->indexName( $m[2] );
3963 return $this->tableName( $m[2] );
3965 } elseif ( isset( $m[3] ) && $m[3] !== '' && array_key_exists( $m[3], $vars ) ) {
3966 return $this->addQuotes( $vars[$m[3]] );
3967 } elseif ( isset( $m[4] ) && $m[4] !== '' && array_key_exists( $m[4], $vars ) ) {
3968 return $this->addIdentifierQuotes( $vars[$m[4]] );
3969 } elseif ( isset( $m[5] ) && $m[5] !== '' && array_key_exists( $m[5], $vars ) ) {
3970 return $vars[$m[5]];
3980 * Get schema variables. If none have been set via setSchemaVars(), then
3981 * use some defaults from the current object.
3985 protected function getSchemaVars() {
3986 if ( $this->schemaVars
) {
3987 return $this->schemaVars
;
3989 return $this->getDefaultSchemaVars();
3994 * Get schema variables to use if none have been set via setSchemaVars().
3996 * Override this in derived classes to provide variables for tables.sql
3997 * and SQL patch files.
4001 protected function getDefaultSchemaVars() {
4005 public function lockIsFree( $lockName, $method ) {
4006 // RDBMs methods for checking named locks may or may not count this thread itself.
4007 // In MySQL, IS_FREE_LOCK() returns 0 if the thread already has the lock. This is
4008 // the behavior choosen by the interface for this method.
4009 return !isset( $this->namedLocksHeld
[$lockName] );
4012 public function lock( $lockName, $method, $timeout = 5 ) {
4013 $this->namedLocksHeld
[$lockName] = 1;
4018 public function unlock( $lockName, $method ) {
4019 unset( $this->namedLocksHeld
[$lockName] );
4024 public function getScopedLockAndFlush( $lockKey, $fname, $timeout ) {
4025 if ( $this->writesOrCallbacksPending() ) {
4026 // This only flushes transactions to clear snapshots, not to write data
4027 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4028 throw new DBUnexpectedError(
4030 "$fname: Cannot flush pre-lock snapshot because writes are pending ($fnames)."
4034 if ( !$this->lock( $lockKey, $fname, $timeout ) ) {
4038 $unlocker = new ScopedCallback( function () use ( $lockKey, $fname ) {
4039 if ( $this->trxLevel() ) {
4040 // There is a good chance an exception was thrown, causing any early return
4041 // from the caller. Let any error handler get a chance to issue rollback().
4042 // If there isn't one, let the error bubble up and trigger server-side rollback.
4043 $this->onTransactionResolution(
4044 function () use ( $lockKey, $fname ) {
4045 $this->unlock( $lockKey, $fname );
4050 $this->unlock( $lockKey, $fname );
4054 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4059 public function namedLocksEnqueue() {
4063 public function tableLocksHaveTransactionScope() {
4067 final public function lockTables( array $read, array $write, $method ) {
4068 if ( $this->writesOrCallbacksPending() ) {
4069 throw new DBUnexpectedError( $this, "Transaction writes or callbacks still pending." );
4072 if ( $this->tableLocksHaveTransactionScope() ) {
4073 $this->startAtomic( $method );
4076 return $this->doLockTables( $read, $write, $method );
4080 * Helper function for lockTables() that handles the actual table locking
4082 * @param array $read Array of tables to lock for read access
4083 * @param array $write Array of tables to lock for write access
4084 * @param string $method Name of caller
4087 protected function doLockTables( array $read, array $write, $method ) {
4091 final public function unlockTables( $method ) {
4092 if ( $this->tableLocksHaveTransactionScope() ) {
4093 $this->endAtomic( $method );
4095 return true; // locks released on COMMIT/ROLLBACK
4098 return $this->doUnlockTables( $method );
4102 * Helper function for unlockTables() that handles the actual table unlocking
4104 * @param string $method Name of caller
4107 protected function doUnlockTables( $method ) {
4113 * @param string $tableName
4114 * @param string $fName
4115 * @return bool|ResultWrapper
4118 public function dropTable( $tableName, $fName = __METHOD__
) {
4119 if ( !$this->tableExists( $tableName, $fName ) ) {
4122 $sql = "DROP TABLE " . $this->tableName( $tableName ) . " CASCADE";
4124 return $this->query( $sql, $fName );
4127 public function getInfinity() {
4131 public function encodeExpiry( $expiry ) {
4132 return ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() )
4133 ?
$this->getInfinity()
4134 : $this->timestamp( $expiry );
4137 public function decodeExpiry( $expiry, $format = TS_MW
) {
4138 if ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() ) {
4142 return ConvertibleTimestamp
::convert( $format, $expiry );
4145 public function setBigSelects( $value = true ) {
4149 public function isReadOnly() {
4150 return ( $this->getReadOnlyReason() !== false );
4154 * @return string|bool Reason this DB is read-only or false if it is not
4156 protected function getReadOnlyReason() {
4157 $reason = $this->getLBInfo( 'readOnlyReason' );
4159 return is_string( $reason ) ?
$reason : false;
4162 public function setTableAliases( array $aliases ) {
4163 $this->tableAliases
= $aliases;
4166 public function setIndexAliases( array $aliases ) {
4167 $this->indexAliases
= $aliases;
4171 * Get the underlying binding connection handle
4173 * Makes sure the connection resource is set (disconnects and ping() failure can unset it).
4174 * This catches broken callers than catch and ignore disconnection exceptions.
4175 * Unlike checking isOpen(), this is safe to call inside of open().
4178 * @throws DBUnexpectedError
4181 protected function getBindingHandle() {
4182 if ( !$this->conn
) {
4183 throw new DBUnexpectedError(
4185 'DB connection was already closed or the connection dropped.'
4196 public function __toString() {
4197 return (string)$this->conn
;
4201 * Make sure that copies do not share the same client binding handle
4202 * @throws DBConnectionError
4204 public function __clone() {
4205 $this->connLogger
->warning(
4206 "Cloning " . static::class . " is not recomended; forking connection:\n" .
4207 ( new RuntimeException() )->getTraceAsString()
4210 if ( $this->isOpen() ) {
4211 // Open a new connection resource without messing with the old one
4212 $this->opened
= false;
4213 $this->conn
= false;
4214 $this->trxEndCallbacks
= []; // don't copy
4215 $this->handleSessionLoss(); // no trx or locks anymore
4216 $this->open( $this->server
, $this->user
, $this->password
, $this->dbName
);
4217 $this->lastPing
= microtime( true );
4222 * Called by serialize. Throw an exception when DB connection is serialized.
4223 * This causes problems on some database engines because the connection is
4224 * not restored on unserialize.
4226 public function __sleep() {
4227 throw new RuntimeException( 'Database serialization may cause problems, since ' .
4228 'the connection is not restored on wakeup.' );
4232 * Run a few simple sanity checks and close dangling connections
4234 public function __destruct() {
4235 if ( $this->trxLevel
&& $this->trxDoneWrites
) {
4236 trigger_error( "Uncommitted DB writes (transaction from {$this->trxFname})." );
4239 $danglingWriters = $this->pendingWriteAndCallbackCallers();
4240 if ( $danglingWriters ) {
4241 $fnames = implode( ', ', $danglingWriters );
4242 trigger_error( "DB transaction writes or callbacks still pending ($fnames)." );
4245 if ( $this->conn
) {
4246 // Avoid connection leaks for sanity. Normally, resources close at script completion.
4247 // The connection might already be closed in zend/hhvm by now, so suppress warnings.
4248 Wikimedia\
suppressWarnings();
4249 $this->closeConnection();
4250 Wikimedia\restoreWarnings
();
4251 $this->conn
= false;
4252 $this->opened
= false;
4257 class_alias( Database
::class, 'DatabaseBase' ); // b/c for old name
4258 class_alias( Database
::class, 'Database' ); // b/c global alias