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 array[] Map of (table => (dbname, schema, prefix) map) */
85 protected $tableAliases = [];
86 /** @var string[] Map of (index alias => index) */
87 protected $indexAliases = [];
88 /** @var bool Whether this PHP instance is for a CLI script */
90 /** @var string Agent name for query profiling */
92 /** @var array Parameters used by initConnection() to establish a connection */
93 protected $connectionParams = [];
94 /** @var BagOStuff APC cache */
96 /** @var LoggerInterface */
97 protected $connLogger;
98 /** @var LoggerInterface */
99 protected $queryLogger;
100 /** @var callable Error logging callback */
101 protected $errorLogger;
102 /** @var callable Deprecation logging callback */
103 protected $deprecationLogger;
105 /** @var resource|null Database connection */
106 protected $conn = null;
108 protected $opened = false;
110 /** @var array[] List of (callable, method name, atomic section id) */
111 protected $trxIdleCallbacks = [];
112 /** @var array[] List of (callable, method name, atomic section id) */
113 protected $trxPreCommitCallbacks = [];
114 /** @var array[] List of (callable, method name, atomic section id) */
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;
124 protected $lbInfo = [];
125 /** @var array|bool */
126 protected $schemaVars = false;
128 protected $sessionVars = [];
129 /** @var array|null */
130 protected $preparedArgs;
131 /** @var string|bool|null Stashed value of html_errors INI setting */
132 protected $htmlErrors;
134 protected $delimiter = ';';
135 /** @var DatabaseDomain */
136 protected $currentDomain;
137 /** @var integer|null Rows affected by the last query to query() or its CRUD wrappers */
138 protected $affectedRowCount;
141 * @var int Transaction status
143 protected $trxStatus = self
::STATUS_TRX_NONE
;
145 * @var Exception|null The last error that caused the status to become STATUS_TRX_ERROR
147 protected $trxStatusCause;
149 * @var array|null If wasKnownStatementRollbackError() prevented trxStatus from being set,
150 * the relevant details are stored here.
152 protected $trxStatusIgnoredCause;
154 * Either 1 if a transaction is active or 0 otherwise.
155 * The other Trx fields may not be meaningfull if this is 0.
159 protected $trxLevel = 0;
161 * Either a short hexidecimal string if a transaction is active or ""
164 * @see Database::trxLevel
166 protected $trxShortId = '';
168 * The UNIX time that the transaction started. Callers can assume that if
169 * snapshot isolation is used, then the data is *at least* up to date to that
170 * point (possibly more up-to-date since the first SELECT defines the snapshot).
173 * @see Database::trxLevel
175 private $trxTimestamp = null;
176 /** @var float Lag estimate at the time of BEGIN */
177 private $trxReplicaLag = null;
179 * Remembers the function name given for starting the most recent transaction via begin().
180 * Used to provide additional context for error reporting.
183 * @see Database::trxLevel
185 private $trxFname = null;
187 * Record if possible write queries were done in the last transaction started
190 * @see Database::trxLevel
192 private $trxDoneWrites = false;
194 * Record if the current transaction was started implicitly due to DBO_TRX being set.
197 * @see Database::trxLevel
199 private $trxAutomatic = false;
201 * Counter for atomic savepoint identifiers. Reset when a new transaction begins.
205 private $trxAtomicCounter = 0;
207 * Array of levels of atomicity within transactions
209 * @var array List of (name, unique ID, savepoint ID)
211 private $trxAtomicLevels = [];
213 * Record if the current transaction was started implicitly by Database::startAtomic
217 private $trxAutomaticAtomic = false;
219 * Track the write query callers of the current transaction
223 private $trxWriteCallers = [];
225 * @var float Seconds spent in write queries for the current transaction
227 private $trxWriteDuration = 0.0;
229 * @var int Number of write queries for the current transaction
231 private $trxWriteQueryCount = 0;
233 * @var int Number of rows affected by write queries for the current transaction
235 private $trxWriteAffectedRows = 0;
237 * @var float Like trxWriteQueryCount but excludes lock-bound, easy to replicate, queries
239 private $trxWriteAdjDuration = 0.0;
241 * @var int Number of write queries counted in trxWriteAdjDuration
243 private $trxWriteAdjQueryCount = 0;
245 * @var float RTT time estimate
247 private $rttEstimate = 0.0;
249 /** @var array Map of (name => 1) for locks obtained via lock() */
250 private $namedLocksHeld = [];
251 /** @var array Map of (table name => 1) for TEMPORARY tables */
252 protected $sessionTempTables = [];
254 /** @var IDatabase|null Lazy handle to the master DB this server replicates from */
255 private $lazyMasterHandle;
257 /** @var float UNIX timestamp */
258 protected $lastPing = 0.0;
260 /** @var int[] Prior flags member variable values */
261 private $priorFlags = [];
263 /** @var callable|null */
265 /** @var TransactionProfiler */
266 protected $trxProfiler;
269 protected $nonNativeInsertSelectBatchSize = 10000;
271 /** @var string Idiom used when a cancelable atomic section started the transaction */
272 private static $NOT_APPLICABLE = 'n/a';
273 /** @var string Prefix to the atomic section counter used to make savepoint IDs */
274 private static $SAVEPOINT_PREFIX = 'wikimedia_rdbms_atomic';
276 /** @var int Transaction is in a error state requiring a full or savepoint rollback */
277 const STATUS_TRX_ERROR
= 1;
278 /** @var int Transaction is active and in a normal state */
279 const STATUS_TRX_OK
= 2;
280 /** @var int No transaction is active */
281 const STATUS_TRX_NONE
= 3;
284 * @note exceptions for missing libraries/drivers should be thrown in initConnection()
285 * @param array $params Parameters passed from Database::factory()
287 protected function __construct( array $params ) {
288 foreach ( [ 'host', 'user', 'password', 'dbname', 'schema', 'tablePrefix' ] as $name ) {
289 $this->connectionParams
[$name] = $params[$name];
292 $this->cliMode
= $params['cliMode'];
293 // Agent name is added to SQL queries in a comment, so make sure it can't break out
294 $this->agent
= str_replace( '/', '-', $params['agent'] );
296 $this->flags
= $params['flags'];
297 if ( $this->flags
& self
::DBO_DEFAULT
) {
298 if ( $this->cliMode
) {
299 $this->flags
&= ~self
::DBO_TRX
;
301 $this->flags |
= self
::DBO_TRX
;
304 // Disregard deprecated DBO_IGNORE flag (T189999)
305 $this->flags
&= ~self
::DBO_IGNORE
;
307 $this->sessionVars
= $params['variables'];
309 $this->srvCache
= $params['srvCache'] ??
new HashBagOStuff();
311 $this->profiler
= is_callable( $params['profiler'] ) ?
$params['profiler'] : null;
312 $this->trxProfiler
= $params['trxProfiler'];
313 $this->connLogger
= $params['connLogger'];
314 $this->queryLogger
= $params['queryLogger'];
315 $this->errorLogger
= $params['errorLogger'];
316 $this->deprecationLogger
= $params['deprecationLogger'];
318 if ( isset( $params['nonNativeInsertSelectBatchSize'] ) ) {
319 $this->nonNativeInsertSelectBatchSize
= $params['nonNativeInsertSelectBatchSize'];
322 // Set initial dummy domain until open() sets the final DB/prefix
323 $this->currentDomain
= new DatabaseDomain(
324 $params['dbname'] != '' ?
$params['dbname'] : null,
325 $params['schema'] != '' ?
$params['schema'] : null,
326 $params['tablePrefix']
331 * Initialize the connection to the database over the wire (or to local files)
333 * @throws LogicException
334 * @throws InvalidArgumentException
335 * @throws DBConnectionError
338 final public function initConnection() {
339 if ( $this->isOpen() ) {
340 throw new LogicException( __METHOD__
. ': already connected.' );
342 // Establish the connection
343 $this->doInitConnection();
347 * Actually connect to the database over the wire (or to local files)
349 * @throws InvalidArgumentException
350 * @throws DBConnectionError
353 protected function doInitConnection() {
354 if ( strlen( $this->connectionParams
['user'] ) ) {
356 $this->connectionParams
['host'],
357 $this->connectionParams
['user'],
358 $this->connectionParams
['password'],
359 $this->connectionParams
['dbname'],
360 $this->connectionParams
['schema'],
361 $this->connectionParams
['tablePrefix']
364 throw new InvalidArgumentException( "No database user provided." );
369 * Open a new connection to the database (closing any existing one)
371 * @param string $server Database server host
372 * @param string $user Database user name
373 * @param string $password Database user password
374 * @param string $dbName Database name
375 * @param string|null $schema Database schema name
376 * @param string $tablePrefix Table prefix
378 * @throws DBConnectionError
380 abstract protected function open( $server, $user, $password, $dbName, $schema, $tablePrefix );
383 * Construct a Database subclass instance given a database type and parameters
385 * This also connects to the database immediately upon object construction
387 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
388 * @param array $p Parameter map with keys:
389 * - host : The hostname of the DB server
390 * - user : The name of the database user the client operates under
391 * - password : The password for the database user
392 * - dbname : The name of the database to use where queries do not specify one.
393 * The database must exist or an error might be thrown. Setting this to the empty string
394 * will avoid any such errors and make the handle have no implicit database scope. This is
395 * useful for queries like SHOW STATUS, CREATE DATABASE, or DROP DATABASE. Note that a
396 * "database" in Postgres is rougly equivalent to an entire MySQL server. This the domain
397 * in which user names and such are defined, e.g. users are database-specific in Postgres.
398 * - schema : The database schema to use (if supported). A "schema" in Postgres is roughly
399 * equivalent to a "database" in MySQL. Note that MySQL and SQLite do not use schemas.
400 * - tablePrefix : Optional table prefix that is implicitly added on to all table names
401 * recognized in queries. This can be used in place of schemas for handle site farms.
402 * - flags : Optional bitfield of DBO_* constants that define connection, protocol,
403 * buffering, and transaction behavior. It is STRONGLY adviced to leave the DBO_DEFAULT
404 * flag in place UNLESS this this database simply acts as a key/value store.
405 * - driver: Optional name of a specific DB client driver. For MySQL, there is only the
406 * 'mysqli' driver; the old one 'mysql' has been removed.
407 * - variables: Optional map of session variables to set after connecting. This can be
408 * used to adjust lock timeouts or encoding modes and the like.
409 * - connLogger: Optional PSR-3 logger interface instance.
410 * - queryLogger: Optional PSR-3 logger interface instance.
411 * - profiler : Optional callback that takes a section name argument and returns
412 * a ScopedCallback instance that ends the profile section in its destructor.
413 * These will be called in query(), using a simplified version of the SQL that
414 * also includes the agent as a SQL comment.
415 * - trxProfiler: Optional TransactionProfiler instance.
416 * - errorLogger: Optional callback that takes an Exception and logs it.
417 * - deprecationLogger: Optional callback that takes a string and logs it.
418 * - cliMode: Whether to consider the execution context that of a CLI script.
419 * - agent: Optional name used to identify the end-user in query profiling/logging.
420 * - srvCache: Optional BagOStuff instance to an APC-style cache.
421 * - nonNativeInsertSelectBatchSize: Optional batch size for non-native INSERT SELECT emulation.
422 * @param int $connect One of the class constants (NEW_CONNECTED, NEW_UNCONNECTED) [optional]
423 * @return Database|null If the database driver or extension cannot be found
424 * @throws InvalidArgumentException If the database driver or extension cannot be found
427 final public static function factory( $dbType, $p = [], $connect = self
::NEW_CONNECTED
) {
428 $class = self
::getClass( $dbType, $p['driver'] ??
null );
430 if ( class_exists( $class ) && is_subclass_of( $class, IDatabase
::class ) ) {
431 // Resolve some defaults for b/c
432 $p['host'] = $p['host'] ??
false;
433 $p['user'] = $p['user'] ??
false;
434 $p['password'] = $p['password'] ??
false;
435 $p['dbname'] = $p['dbname'] ??
false;
436 $p['flags'] = $p['flags'] ??
0;
437 $p['variables'] = $p['variables'] ??
[];
438 $p['tablePrefix'] = $p['tablePrefix'] ??
'';
439 $p['schema'] = $p['schema'] ??
null;
440 $p['cliMode'] = $p['cliMode'] ??
( PHP_SAPI
=== 'cli' || PHP_SAPI
=== 'phpdbg' );
441 $p['agent'] = $p['agent'] ??
'';
442 if ( !isset( $p['connLogger'] ) ) {
443 $p['connLogger'] = new NullLogger();
445 if ( !isset( $p['queryLogger'] ) ) {
446 $p['queryLogger'] = new NullLogger();
448 $p['profiler'] = $p['profiler'] ??
null;
449 if ( !isset( $p['trxProfiler'] ) ) {
450 $p['trxProfiler'] = new TransactionProfiler();
452 if ( !isset( $p['errorLogger'] ) ) {
453 $p['errorLogger'] = function ( Exception
$e ) {
454 trigger_error( get_class( $e ) . ': ' . $e->getMessage(), E_USER_WARNING
);
457 if ( !isset( $p['deprecationLogger'] ) ) {
458 $p['deprecationLogger'] = function ( $msg ) {
459 trigger_error( $msg, E_USER_DEPRECATED
);
463 /** @var Database $conn */
464 $conn = new $class( $p );
465 if ( $connect == self
::NEW_CONNECTED
) {
466 $conn->initConnection();
476 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
477 * @param string|null $driver Optional name of a specific DB client driver
478 * @return array Map of (Database::ATTRIBUTE_* constant => value) for all such constants
479 * @throws InvalidArgumentException
482 final public static function attributesFromType( $dbType, $driver = null ) {
483 static $defaults = [ self
::ATTR_DB_LEVEL_LOCKING
=> false ];
485 $class = self
::getClass( $dbType, $driver );
487 return call_user_func( [ $class, 'getAttributes' ] ) +
$defaults;
491 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
492 * @param string|null $driver Optional name of a specific DB client driver
493 * @return string Database subclass name to use
494 * @throws InvalidArgumentException
496 private static function getClass( $dbType, $driver = null ) {
497 // For database types with built-in support, the below maps type to IDatabase
498 // implementations. For types with multipe driver implementations (PHP extensions),
499 // an array can be used, keyed by extension name. In case of an array, the
500 // optional 'driver' parameter can be used to force a specific driver. Otherwise,
501 // we auto-detect the first available driver. For types without built-in support,
502 // an class named "Database<Type>" us used, eg. DatabaseFoo for type 'foo'.
503 static $builtinTypes = [
504 'mssql' => DatabaseMssql
::class,
505 'mysql' => [ 'mysqli' => DatabaseMysqli
::class ],
506 'sqlite' => DatabaseSqlite
::class,
507 'postgres' => DatabasePostgres
::class,
510 $dbType = strtolower( $dbType );
513 if ( isset( $builtinTypes[$dbType] ) ) {
514 $possibleDrivers = $builtinTypes[$dbType];
515 if ( is_string( $possibleDrivers ) ) {
516 $class = $possibleDrivers;
518 if ( (string)$driver !== '' ) {
519 if ( !isset( $possibleDrivers[$driver] ) ) {
520 throw new InvalidArgumentException( __METHOD__
.
521 " type '$dbType' does not support driver '{$driver}'" );
523 $class = $possibleDrivers[$driver];
526 foreach ( $possibleDrivers as $posDriver => $possibleClass ) {
527 if ( extension_loaded( $posDriver ) ) {
528 $class = $possibleClass;
535 $class = 'Database' . ucfirst( $dbType );
538 if ( $class === false ) {
539 throw new InvalidArgumentException( __METHOD__
.
540 " no viable database extension found for type '$dbType'" );
547 * @return array Map of (Database::ATTRIBUTE_* constant => value
550 protected static function getAttributes() {
555 * Set the PSR-3 logger interface to use for query logging. (The logger
556 * interfaces for connection logging and error logging can be set with the
559 * @param LoggerInterface $logger
561 public function setLogger( LoggerInterface
$logger ) {
562 $this->queryLogger
= $logger;
565 public function getServerInfo() {
566 return $this->getServerVersion();
569 public function bufferResults( $buffer = null ) {
570 $res = !$this->getFlag( self
::DBO_NOBUFFER
);
571 if ( $buffer !== null ) {
573 ?
$this->clearFlag( self
::DBO_NOBUFFER
)
574 : $this->setFlag( self
::DBO_NOBUFFER
);
580 public function trxLevel() {
581 return $this->trxLevel
;
584 public function trxTimestamp() {
585 return $this->trxLevel ?
$this->trxTimestamp
: null;
589 * @return int One of the STATUS_TRX_* class constants
592 public function trxStatus() {
593 return $this->trxStatus
;
596 public function tablePrefix( $prefix = null ) {
597 $old = $this->currentDomain
->getTablePrefix();
598 if ( $prefix !== null ) {
599 $this->currentDomain
= new DatabaseDomain(
600 $this->currentDomain
->getDatabase(),
601 $this->currentDomain
->getSchema(),
609 public function dbSchema( $schema = null ) {
610 $old = $this->currentDomain
->getSchema();
611 if ( $schema !== null ) {
612 $this->currentDomain
= new DatabaseDomain(
613 $this->currentDomain
->getDatabase(),
614 // DatabaseDomain uses null for unspecified schemas
615 strlen( $schema ) ?
$schema : null,
616 $this->currentDomain
->getTablePrefix()
624 * @return string Schema to use to qualify relations in queries
626 protected function relationSchemaQualifier() {
627 return $this->dbSchema();
630 public function getLBInfo( $name = null ) {
631 if ( is_null( $name ) ) {
632 return $this->lbInfo
;
634 if ( array_key_exists( $name, $this->lbInfo
) ) {
635 return $this->lbInfo
[$name];
642 public function setLBInfo( $name, $value = null ) {
643 if ( is_null( $value ) ) {
644 $this->lbInfo
= $name;
646 $this->lbInfo
[$name] = $value;
650 public function setLazyMasterHandle( IDatabase
$conn ) {
651 $this->lazyMasterHandle
= $conn;
655 * @return IDatabase|null
656 * @see setLazyMasterHandle()
659 protected function getLazyMasterHandle() {
660 return $this->lazyMasterHandle
;
663 public function implicitGroupby() {
667 public function implicitOrderby() {
671 public function lastQuery() {
672 return $this->lastQuery
;
675 public function doneWrites() {
676 return (bool)$this->lastWriteTime
;
679 public function lastDoneWrites() {
680 return $this->lastWriteTime ?
: false;
683 public function writesPending() {
684 return $this->trxLevel
&& $this->trxDoneWrites
;
687 public function writesOrCallbacksPending() {
688 return $this->trxLevel
&& (
689 $this->trxDoneWrites ||
690 $this->trxIdleCallbacks ||
691 $this->trxPreCommitCallbacks ||
692 $this->trxEndCallbacks
696 public function preCommitCallbacksPending() {
697 return $this->trxLevel
&& $this->trxPreCommitCallbacks
;
701 * @return string|null
703 final protected function getTransactionRoundId() {
704 // If transaction round participation is enabled, see if one is active
705 if ( $this->getFlag( self
::DBO_TRX
) ) {
706 $id = $this->getLBInfo( 'trxRoundId' );
708 return is_string( $id ) ?
$id : null;
714 public function pendingWriteQueryDuration( $type = self
::ESTIMATE_TOTAL
) {
715 if ( !$this->trxLevel
) {
717 } elseif ( !$this->trxDoneWrites
) {
722 case self
::ESTIMATE_DB_APPLY
:
723 return $this->pingAndCalculateLastTrxApplyTime();
724 default: // everything
725 return $this->trxWriteDuration
;
730 * @return float Time to apply writes to replicas based on trxWrite* fields
732 private function pingAndCalculateLastTrxApplyTime() {
735 $rttAdjTotal = $this->trxWriteAdjQueryCount
* $rtt;
736 $applyTime = max( $this->trxWriteAdjDuration
- $rttAdjTotal, 0 );
737 // For omitted queries, make them count as something at least
738 $omitted = $this->trxWriteQueryCount
- $this->trxWriteAdjQueryCount
;
739 $applyTime +
= self
::TINY_WRITE_SEC
* $omitted;
744 public function pendingWriteCallers() {
745 return $this->trxLevel ?
$this->trxWriteCallers
: [];
748 public function pendingWriteRowsAffected() {
749 return $this->trxWriteAffectedRows
;
753 * List the methods that have write queries or callbacks for the current transaction
755 * This method should not be used outside of Database/LoadBalancer
760 public function pendingWriteAndCallbackCallers() {
761 $fnames = $this->pendingWriteCallers();
763 $this->trxIdleCallbacks
,
764 $this->trxPreCommitCallbacks
,
765 $this->trxEndCallbacks
767 foreach ( $callbacks as $callback ) {
768 $fnames[] = $callback[1];
778 private function flatAtomicSectionList() {
779 return array_reduce( $this->trxAtomicLevels
, function ( $accum, $v ) {
780 return $accum === null ?
$v[0] : "$accum, " . $v[0];
784 public function isOpen() {
785 return $this->opened
;
788 public function setFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
789 if ( ( $flag & self
::DBO_IGNORE
) ) {
790 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
793 if ( $remember === self
::REMEMBER_PRIOR
) {
794 array_push( $this->priorFlags
, $this->flags
);
796 $this->flags |
= $flag;
799 public function clearFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
800 if ( ( $flag & self
::DBO_IGNORE
) ) {
801 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
804 if ( $remember === self
::REMEMBER_PRIOR
) {
805 array_push( $this->priorFlags
, $this->flags
);
807 $this->flags
&= ~
$flag;
810 public function restoreFlags( $state = self
::RESTORE_PRIOR
) {
811 if ( !$this->priorFlags
) {
815 if ( $state === self
::RESTORE_INITIAL
) {
816 $this->flags
= reset( $this->priorFlags
);
817 $this->priorFlags
= [];
819 $this->flags
= array_pop( $this->priorFlags
);
823 public function getFlag( $flag ) {
824 return (bool)( $this->flags
& $flag );
828 * @param string $name Class field name
830 * @deprecated Since 1.28
832 public function getProperty( $name ) {
836 public function getDomainID() {
837 return $this->currentDomain
->getId();
840 final public function getWikiID() {
841 return $this->getDomainID();
845 * Get information about an index into an object
846 * @param string $table Table name
847 * @param string $index Index name
848 * @param string $fname Calling function name
849 * @return mixed Database-specific index description class or false if the index does not exist
851 abstract function indexInfo( $table, $index, $fname = __METHOD__
);
854 * Wrapper for addslashes()
856 * @param string $s String to be slashed.
857 * @return string Slashed string.
859 abstract function strencode( $s );
862 * Set a custom error handler for logging errors during database connection
864 protected function installErrorHandler() {
865 $this->phpError
= false;
866 $this->htmlErrors
= ini_set( 'html_errors', '0' );
867 set_error_handler( [ $this, 'connectionErrorLogger' ] );
871 * Restore the previous error handler and return the last PHP error for this DB
873 * @return bool|string
875 protected function restoreErrorHandler() {
876 restore_error_handler();
877 if ( $this->htmlErrors
!== false ) {
878 ini_set( 'html_errors', $this->htmlErrors
);
881 return $this->getLastPHPError();
885 * @return string|bool Last PHP error for this DB (typically connection errors)
887 protected function getLastPHPError() {
888 if ( $this->phpError
) {
889 $error = preg_replace( '!\[<a.*</a>\]!', '', $this->phpError
);
890 $error = preg_replace( '!^.*?:\s?(.*)$!', '$1', $error );
899 * Error handler for logging errors during database connection
900 * This method should not be used outside of Database classes
903 * @param string $errstr
905 public function connectionErrorLogger( $errno, $errstr ) {
906 $this->phpError
= $errstr;
910 * Create a log context to pass to PSR-3 logger functions.
912 * @param array $extras Additional data to add to context
915 protected function getLogContext( array $extras = [] ) {
918 'db_server' => $this->server
,
919 'db_name' => $this->getDBname(),
920 'db_user' => $this->user
,
926 final public function close() {
927 $exception = null; // error to throw after disconnecting
929 $wasOpen = $this->opened
;
930 // This should mostly do nothing if the connection is already closed
932 // Roll back any dangling transaction first
933 if ( $this->trxLevel
) {
934 if ( $this->trxAtomicLevels
) {
935 // Cannot let incomplete atomic sections be committed
936 $levels = $this->flatAtomicSectionList();
937 $exception = new DBUnexpectedError(
939 __METHOD__
. ": atomic sections $levels are still open."
941 } elseif ( $this->trxAutomatic
) {
942 // Only the connection manager can commit non-empty DBO_TRX transactions
943 // (empty ones we can silently roll back)
944 if ( $this->writesOrCallbacksPending() ) {
945 $exception = new DBUnexpectedError(
948 ": mass commit/rollback of peer transaction required (DBO_TRX set)."
952 // Manual transactions should have been committed or rolled
953 // back, even if empty.
954 $exception = new DBUnexpectedError(
956 __METHOD__
. ": transaction is still open (from {$this->trxFname})."
960 if ( $this->trxEndCallbacksSuppressed
) {
961 $exception = $exception ?
: new DBUnexpectedError(
963 __METHOD__
. ': callbacks are suppressed; cannot properly commit.'
967 // Rollback the changes and run any callbacks as needed
968 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
971 // Close the actual connection in the binding handle
972 $closed = $this->closeConnection();
974 $closed = true; // already closed; nothing to do
978 $this->opened
= false;
980 // Throw any unexpected errors after having disconnected
981 if ( $exception instanceof Exception
) {
985 // Note that various subclasses call close() at the start of open(), which itself is
986 // called by replaceLostConnection(). In that case, just because onTransactionResolution()
987 // callbacks are pending does not mean that an exception should be thrown. Rather, they
988 // will be executed after the reconnection step.
990 // Sanity check that no callbacks are dangling
991 $fnames = $this->pendingWriteAndCallbackCallers();
993 throw new RuntimeException(
994 "Transaction callbacks are still pending:\n" . implode( ', ', $fnames )
1003 * Make sure there is an open connection handle (alive or not) as a sanity check
1005 * This guards against fatal errors to the binding handle not being defined
1006 * in cases where open() was never called or close() was already called
1008 * @throws DBUnexpectedError
1010 protected function assertHasConnectionHandle() {
1011 if ( !$this->isOpen() ) {
1012 throw new DBUnexpectedError( $this, "DB connection was already closed." );
1017 * Make sure that this server is not marked as a replica nor read-only as a sanity check
1019 * @throws DBUnexpectedError
1021 protected function assertIsWritableMaster() {
1022 if ( $this->getLBInfo( 'replica' ) === true ) {
1023 throw new DBUnexpectedError(
1025 'Write operations are not allowed on replica database connections.'
1028 $reason = $this->getReadOnlyReason();
1029 if ( $reason !== false ) {
1030 throw new DBReadOnlyError( $this, "Database is read-only: $reason" );
1035 * Closes underlying database connection
1037 * @return bool Whether connection was closed successfully
1039 abstract protected function closeConnection();
1042 * @deprecated since 1.32
1043 * @param string $error Fallback message, if none is given by DB
1044 * @throws DBConnectionError
1046 public function reportConnectionError( $error = 'Unknown error' ) {
1047 call_user_func( $this->deprecationLogger
, 'Use of ' . __METHOD__
. ' is deprecated.' );
1048 throw new DBConnectionError( $this, $this->lastError() ?
: $error );
1052 * Run a query and return a DBMS-dependent wrapper or boolean
1054 * For SELECT queries, this returns either:
1055 * - a) A driver-specific value/resource, only on success. This can be iterated
1056 * over by calling fetchObject()/fetchRow() until there are no more rows.
1057 * Alternatively, the result can be passed to resultObject() to obtain a
1058 * ResultWrapper instance which can then be iterated over via "foreach".
1059 * - b) False, on any query failure
1061 * For non-SELECT queries, this returns either:
1062 * - a) A driver-specific value/resource, only on success
1063 * - b) True, only on success (e.g. no meaningful result other than "OK")
1064 * - c) False, on any query failure
1066 * @param string $sql SQL query
1067 * @return mixed|bool An object, resource, or true on success; false on failure
1069 abstract protected function doQuery( $sql );
1072 * Determine whether a query writes to the DB. When in doubt, this returns true.
1076 * - Subsequent web requests should not need to wait for replication from
1077 * the master position seen by this web request, unless this request made
1078 * changes to the master. This is handled by ChronologyProtector by checking
1079 * doneWrites() at the end of the request. doneWrites() returns true if any
1080 * query set lastWriteTime; which query() does based on isWriteQuery().
1082 * - Reject write queries to replica DBs, in query().
1084 * @param string $sql
1087 protected function isWriteQuery( $sql ) {
1088 // BEGIN and COMMIT queries are considered read queries here.
1089 // Database backends and drivers (MySQL, MariaDB, php-mysqli) generally
1090 // treat these as write queries, in that their results have "affected rows"
1091 // as meta data as from writes, instead of "num rows" as from reads.
1092 // But, we treat them as read queries because when reading data (from
1093 // either replica or master) we use transactions to enable repeatable-read
1094 // snapshots, which ensures we get consistent results from the same snapshot
1095 // for all queries within a request. Use cases:
1096 // - Treating these as writes would trigger ChronologyProtector (see method doc).
1097 // - We use this method to reject writes to replicas, but we need to allow
1098 // use of transactions on replicas for read snapshots. This fine given
1099 // that transactions by themselves don't make changes, only actual writes
1100 // within the transaction matter, which we still detect.
1102 '/^(?:SELECT|BEGIN|ROLLBACK|COMMIT|SAVEPOINT|RELEASE|SET|SHOW|EXPLAIN|\(SELECT)\b/i',
1108 * @param string $sql
1109 * @return string|null
1111 protected function getQueryVerb( $sql ) {
1112 return preg_match( '/^\s*([a-z]+)/i', $sql, $m ) ?
strtoupper( $m[1] ) : null;
1116 * Determine whether a SQL statement is sensitive to isolation level.
1118 * A SQL statement is considered transactable if its result could vary
1119 * depending on the transaction isolation level. Operational commands
1120 * such as 'SET' and 'SHOW' are not considered to be transactable.
1122 * Main purpose: Used by query() to decide whether to begin a transaction
1123 * before the current query (in DBO_TRX mode, on by default).
1125 * @param string $sql
1128 protected function isTransactableQuery( $sql ) {
1130 $this->getQueryVerb( $sql ),
1131 [ 'BEGIN', 'ROLLBACK', 'COMMIT', 'SET', 'SHOW', 'CREATE', 'ALTER' ],
1137 * @param string $sql A SQL query
1138 * @return bool Whether $sql is SQL for TEMPORARY table operation
1140 protected function registerTempTableOperation( $sql ) {
1142 '/^CREATE\s+TEMPORARY\s+TABLE\s+(?:IF\s+NOT\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1146 $this->sessionTempTables
[$matches[1]] = 1;
1149 } elseif ( preg_match(
1150 '/^DROP\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1154 $isTemp = isset( $this->sessionTempTables
[$matches[1]] );
1155 unset( $this->sessionTempTables
[$matches[1]] );
1158 } elseif ( preg_match(
1159 '/^TRUNCATE\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1163 return isset( $this->sessionTempTables
[$matches[1]] );
1164 } elseif ( preg_match(
1165 '/^(?:INSERT\s+(?:\w+\s+)?INTO|UPDATE|DELETE\s+FROM)\s+[`"\']?(\w+)[`"\']?/i',
1169 return isset( $this->sessionTempTables
[$matches[1]] );
1175 public function query( $sql, $fname = __METHOD__
, $tempIgnore = false ) {
1176 $this->assertTransactionStatus( $sql, $fname );
1177 $this->assertHasConnectionHandle();
1179 $priorTransaction = $this->trxLevel
;
1180 $priorWritesPending = $this->writesOrCallbacksPending();
1181 $this->lastQuery
= $sql;
1183 if ( $this->isWriteQuery( $sql ) ) {
1184 # In theory, non-persistent writes are allowed in read-only mode, but due to things
1185 # like https://bugs.mysql.com/bug.php?id=33669 that might not work anyway...
1186 $this->assertIsWritableMaster();
1187 # Avoid treating temporary table operations as meaningful "writes"
1188 $isEffectiveWrite = !$this->registerTempTableOperation( $sql );
1190 $isEffectiveWrite = false;
1193 # Add trace comment to the begin of the sql string, right after the operator.
1194 # Or, for one-word queries (like "BEGIN" or COMMIT") add it to the end (T44598)
1195 $commentedSql = preg_replace( '/\s|$/', " /* $fname {$this->agent} */ ", $sql, 1 );
1197 # Send the query to the server and fetch any corresponding errors
1198 $ret = $this->attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname );
1199 $lastError = $this->lastError();
1200 $lastErrno = $this->lastErrno();
1202 $recoverableSR = false; // recoverable statement rollback?
1203 $recoverableCL = false; // recoverable connection loss?
1205 if ( $ret === false && $this->wasConnectionLoss() ) {
1206 # Check if no meaningful session state was lost
1207 $recoverableCL = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
1208 # Update session state tracking and try to restore the connection
1209 $reconnected = $this->replaceLostConnection( __METHOD__
);
1210 # Silently resend the query to the server if it is safe and possible
1211 if ( $recoverableCL && $reconnected ) {
1212 $ret = $this->attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname );
1213 $lastError = $this->lastError();
1214 $lastErrno = $this->lastErrno();
1216 if ( $ret === false && $this->wasConnectionLoss() ) {
1217 # Query probably causes disconnects; reconnect and do not re-run it
1218 $this->replaceLostConnection( __METHOD__
);
1220 $recoverableCL = false; // connection does not need recovering
1221 $recoverableSR = $this->wasKnownStatementRollbackError();
1225 $recoverableSR = $this->wasKnownStatementRollbackError();
1228 if ( $ret === false ) {
1229 if ( $priorTransaction ) {
1230 if ( $recoverableSR ) {
1231 # We're ignoring an error that caused just the current query to be aborted.
1232 # But log the cause so we can log a deprecation notice if a caller actually
1234 $this->trxStatusIgnoredCause
= [ $lastError, $lastErrno, $fname ];
1235 } elseif ( !$recoverableCL ) {
1236 # Either the query was aborted or all queries after BEGIN where aborted.
1237 # In the first case, the only options going forward are (a) ROLLBACK, or
1238 # (b) ROLLBACK TO SAVEPOINT (if one was set). If the later case, the only
1239 # option is ROLLBACK, since the snapshots would have been released.
1240 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
1241 $this->trxStatusCause
=
1242 $this->getQueryExceptionAndLog( $lastError, $lastErrno, $sql, $fname );
1243 $tempIgnore = false; // cannot recover
1244 $this->trxStatusIgnoredCause
= null;
1248 $this->reportQueryError( $lastError, $lastErrno, $sql, $fname, $tempIgnore );
1251 return $this->resultObject( $ret );
1255 * Wrapper for query() that also handles profiling, logging, and affected row count updates
1257 * @param string $sql Original SQL query
1258 * @param string $commentedSql SQL query with debugging/trace comment
1259 * @param bool $isEffectiveWrite Whether the query is a (non-temporary table) write
1260 * @param string $fname Name of the calling function
1261 * @return bool|ResultWrapper True for a successful write query, ResultWrapper
1262 * object for a successful read query, or false on failure
1264 private function attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname ) {
1265 $this->beginIfImplied( $sql, $fname );
1267 # Keep track of whether the transaction has write queries pending
1268 if ( $isEffectiveWrite ) {
1269 $this->lastWriteTime
= microtime( true );
1270 if ( $this->trxLevel
&& !$this->trxDoneWrites
) {
1271 $this->trxDoneWrites
= true;
1272 $this->trxProfiler
->transactionWritingIn(
1273 $this->server
, $this->getDomainID(), $this->trxShortId
);
1277 if ( $this->getFlag( self
::DBO_DEBUG
) ) {
1278 $this->queryLogger
->debug( "{$this->getDomainID()} {$commentedSql}" );
1281 $isMaster = !is_null( $this->getLBInfo( 'master' ) );
1282 # generalizeSQL() will probably cut down the query to reasonable
1283 # logging size most of the time. The substr is really just a sanity check.
1285 $queryProf = 'query-m: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1287 $queryProf = 'query: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1290 # Include query transaction state
1291 $queryProf .= $this->trxShortId ?
" [TRX#{$this->trxShortId}]" : "";
1293 $startTime = microtime( true );
1294 $ps = $this->profiler ?
( $this->profiler
)( $queryProf ) : null;
1295 $this->affectedRowCount
= null;
1296 $ret = $this->doQuery( $commentedSql );
1297 $this->affectedRowCount
= $this->affectedRows();
1298 unset( $ps ); // profile out (if set)
1299 $queryRuntime = max( microtime( true ) - $startTime, 0.0 );
1301 if ( $ret !== false ) {
1302 $this->lastPing
= $startTime;
1303 if ( $isEffectiveWrite && $this->trxLevel
) {
1304 $this->updateTrxWriteQueryTime( $sql, $queryRuntime, $this->affectedRows() );
1305 $this->trxWriteCallers
[] = $fname;
1309 if ( $sql === self
::PING_QUERY
) {
1310 $this->rttEstimate
= $queryRuntime;
1313 $this->trxProfiler
->recordQueryCompletion(
1317 $isEffectiveWrite ?
$this->affectedRows() : $this->numRows( $ret )
1319 $this->queryLogger
->debug( $sql, [
1321 'master' => $isMaster,
1322 'runtime' => $queryRuntime,
1329 * Start an implicit transaction if DBO_TRX is enabled and no transaction is active
1331 * @param string $sql
1332 * @param string $fname
1334 private function beginIfImplied( $sql, $fname ) {
1337 $this->getFlag( self
::DBO_TRX
) &&
1338 $this->isTransactableQuery( $sql )
1340 $this->begin( __METHOD__
. " ($fname)", self
::TRANSACTION_INTERNAL
);
1341 $this->trxAutomatic
= true;
1346 * Update the estimated run-time of a query, not counting large row lock times
1348 * LoadBalancer can be set to rollback transactions that will create huge replication
1349 * lag. It bases this estimate off of pendingWriteQueryDuration(). Certain simple
1350 * queries, like inserting a row can take a long time due to row locking. This method
1351 * uses some simple heuristics to discount those cases.
1353 * @param string $sql A SQL write query
1354 * @param float $runtime Total runtime, including RTT
1355 * @param int $affected Affected row count
1357 private function updateTrxWriteQueryTime( $sql, $runtime, $affected ) {
1358 // Whether this is indicative of replica DB runtime (except for RBR or ws_repl)
1359 $indicativeOfReplicaRuntime = true;
1360 if ( $runtime > self
::SLOW_WRITE_SEC
) {
1361 $verb = $this->getQueryVerb( $sql );
1362 // insert(), upsert(), replace() are fast unless bulky in size or blocked on locks
1363 if ( $verb === 'INSERT' ) {
1364 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
;
1365 } elseif ( $verb === 'REPLACE' ) {
1366 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
/ 2;
1370 $this->trxWriteDuration +
= $runtime;
1371 $this->trxWriteQueryCount +
= 1;
1372 $this->trxWriteAffectedRows +
= $affected;
1373 if ( $indicativeOfReplicaRuntime ) {
1374 $this->trxWriteAdjDuration +
= $runtime;
1375 $this->trxWriteAdjQueryCount +
= 1;
1380 * Error out if the DB is not in a valid state for a query via query()
1382 * @param string $sql
1383 * @param string $fname
1384 * @throws DBTransactionStateError
1386 private function assertTransactionStatus( $sql, $fname ) {
1387 $verb = $this->getQueryVerb( $sql );
1388 if ( $verb === 'USE' ) {
1389 throw new DBUnexpectedError( $this, "Got USE query; use selectDomain() instead." );
1392 if ( $verb === 'ROLLBACK' ) { // transaction/savepoint
1396 if ( $this->trxStatus
< self
::STATUS_TRX_OK
) {
1397 throw new DBTransactionStateError(
1399 "Cannot execute query from $fname while transaction status is ERROR.",
1401 $this->trxStatusCause
1403 } elseif ( $this->trxStatus
=== self
::STATUS_TRX_OK
&& $this->trxStatusIgnoredCause
) {
1404 list( $iLastError, $iLastErrno, $iFname ) = $this->trxStatusIgnoredCause
;
1405 call_user_func( $this->deprecationLogger
,
1406 "Caller from $fname ignored an error originally raised from $iFname: " .
1407 "[$iLastErrno] $iLastError"
1409 $this->trxStatusIgnoredCause
= null;
1413 public function assertNoOpenTransactions() {
1414 if ( $this->explicitTrxActive() ) {
1415 throw new DBTransactionError(
1417 "Explicit transaction still active. A caller may have caught an error. "
1418 . "Open transactions: " . $this->flatAtomicSectionList()
1424 * Determine whether it is safe to retry queries after a database connection is lost
1426 * @param string $sql SQL query
1427 * @param bool $priorWritesPending Whether there is a transaction open with
1428 * possible write queries or transaction pre-commit/idle callbacks
1429 * waiting on it to finish.
1430 * @return bool True if it is safe to retry the query, false otherwise
1432 private function canRecoverFromDisconnect( $sql, $priorWritesPending ) {
1433 # Transaction dropped; this can mean lost writes, or REPEATABLE-READ snapshots.
1434 # Dropped connections also mean that named locks are automatically released.
1435 # Only allow error suppression in autocommit mode or when the lost transaction
1436 # didn't matter anyway (aside from DBO_TRX snapshot loss).
1437 if ( $this->namedLocksHeld
) {
1438 return false; // possible critical section violation
1439 } elseif ( $this->sessionTempTables
) {
1440 return false; // tables might be queried latter
1441 } elseif ( $sql === 'COMMIT' ) {
1442 return !$priorWritesPending; // nothing written anyway? (T127428)
1443 } elseif ( $sql === 'ROLLBACK' ) {
1444 return true; // transaction lost...which is also what was requested :)
1445 } elseif ( $this->explicitTrxActive() ) {
1446 return false; // don't drop atomocity and explicit snapshots
1447 } elseif ( $priorWritesPending ) {
1448 return false; // prior writes lost from implicit transaction
1455 * Clean things up after session (and thus transaction) loss before reconnect
1457 private function handleSessionLossPreconnect() {
1458 // Clean up tracking of session-level things...
1459 // https://dev.mysql.com/doc/refman/5.7/en/implicit-commit.html
1460 // https://www.postgresql.org/docs/9.2/static/sql-createtable.html (ignoring ON COMMIT)
1461 $this->sessionTempTables
= [];
1462 // https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1463 // https://www.postgresql.org/docs/9.4/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1464 $this->namedLocksHeld
= [];
1465 // Session loss implies transaction loss
1466 $this->trxLevel
= 0;
1467 $this->trxAtomicCounter
= 0;
1468 $this->trxIdleCallbacks
= []; // T67263; transaction already lost
1469 $this->trxPreCommitCallbacks
= []; // T67263; transaction already lost
1470 // @note: leave trxRecurringCallbacks in place
1471 if ( $this->trxDoneWrites
) {
1472 $this->trxProfiler
->transactionWritingOut(
1474 $this->getDomainID(),
1476 $this->pendingWriteQueryDuration( self
::ESTIMATE_TOTAL
),
1477 $this->trxWriteAffectedRows
1483 * Clean things up after session (and thus transaction) loss after reconnect
1485 private function handleSessionLossPostconnect() {
1487 // Handle callbacks in trxEndCallbacks, e.g. onTransactionResolution().
1488 // If callback suppression is set then the array will remain unhandled.
1489 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
1490 } catch ( Exception
$ex ) {
1491 // Already logged; move on...
1494 // Handle callbacks in trxRecurringCallbacks, e.g. setTransactionListener()
1495 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
1496 } catch ( Exception
$ex ) {
1497 // Already logged; move on...
1502 * Checks whether the cause of the error is detected to be a timeout.
1504 * It returns false by default, and not all engines support detecting this yet.
1505 * If this returns false, it will be treated as a generic query error.
1507 * @param string $error Error text
1508 * @param int $errno Error number
1511 protected function wasQueryTimeout( $error, $errno ) {
1516 * Report a query error. Log the error, and if neither the object ignore
1517 * flag nor the $tempIgnore flag is set, throw a DBQueryError.
1519 * @param string $error
1521 * @param string $sql
1522 * @param string $fname
1523 * @param bool $tempIgnore
1524 * @throws DBQueryError
1526 public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
1527 if ( $tempIgnore ) {
1528 $this->queryLogger
->debug( "SQL ERROR (ignored): $error\n" );
1530 $exception = $this->getQueryExceptionAndLog( $error, $errno, $sql, $fname );
1537 * @param string $error
1538 * @param string|int $errno
1539 * @param string $sql
1540 * @param string $fname
1543 private function getQueryExceptionAndLog( $error, $errno, $sql, $fname ) {
1544 $sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
1545 $this->queryLogger
->error(
1546 "{fname}\t{db_server}\t{errno}\t{error}\t{sql1line}",
1547 $this->getLogContext( [
1548 'method' => __METHOD__
,
1551 'sql1line' => $sql1line,
1553 'trace' => ( new RuntimeException() )->getTraceAsString()
1556 $this->queryLogger
->debug( "SQL ERROR: " . $error . "\n" );
1557 $wasQueryTimeout = $this->wasQueryTimeout( $error, $errno );
1558 if ( $wasQueryTimeout ) {
1559 $e = new DBQueryTimeoutError( $this, $error, $errno, $sql, $fname );
1561 $e = new DBQueryError( $this, $error, $errno, $sql, $fname );
1567 public function freeResult( $res ) {
1570 public function selectField(
1571 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1573 if ( $var === '*' ) { // sanity
1574 throw new DBUnexpectedError( $this, "Cannot use a * field: got '$var'" );
1577 if ( !is_array( $options ) ) {
1578 $options = [ $options ];
1581 $options['LIMIT'] = 1;
1583 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1584 if ( $res === false ||
!$this->numRows( $res ) ) {
1588 $row = $this->fetchRow( $res );
1590 if ( $row !== false ) {
1591 return reset( $row );
1597 public function selectFieldValues(
1598 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1600 if ( $var === '*' ) { // sanity
1601 throw new DBUnexpectedError( $this, "Cannot use a * field" );
1602 } elseif ( !is_string( $var ) ) { // sanity
1603 throw new DBUnexpectedError( $this, "Cannot use an array of fields" );
1606 if ( !is_array( $options ) ) {
1607 $options = [ $options ];
1610 $res = $this->select( $table, [ 'value' => $var ], $cond, $fname, $options, $join_conds );
1611 if ( $res === false ) {
1616 foreach ( $res as $row ) {
1617 $values[] = $row->value
;
1624 * Returns an optional USE INDEX clause to go after the table, and a
1625 * string to go at the end of the query.
1627 * @param array $options Associative array of options to be turned into
1628 * an SQL query, valid keys are listed in the function.
1630 * @see Database::select()
1632 protected function makeSelectOptions( $options ) {
1633 $preLimitTail = $postLimitTail = '';
1638 foreach ( $options as $key => $option ) {
1639 if ( is_numeric( $key ) ) {
1640 $noKeyOptions[$option] = true;
1644 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1646 $preLimitTail .= $this->makeOrderBy( $options );
1648 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1649 $postLimitTail .= ' FOR UPDATE';
1652 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1653 $postLimitTail .= ' LOCK IN SHARE MODE';
1656 if ( isset( $noKeyOptions['DISTINCT'] ) ||
isset( $noKeyOptions['DISTINCTROW'] ) ) {
1657 $startOpts .= 'DISTINCT';
1660 # Various MySQL extensions
1661 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) {
1662 $startOpts .= ' /*! STRAIGHT_JOIN */';
1665 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) {
1666 $startOpts .= ' HIGH_PRIORITY';
1669 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) {
1670 $startOpts .= ' SQL_BIG_RESULT';
1673 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) {
1674 $startOpts .= ' SQL_BUFFER_RESULT';
1677 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) {
1678 $startOpts .= ' SQL_SMALL_RESULT';
1681 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) {
1682 $startOpts .= ' SQL_CALC_FOUND_ROWS';
1685 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) {
1686 $startOpts .= ' SQL_CACHE';
1689 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) {
1690 $startOpts .= ' SQL_NO_CACHE';
1693 if ( isset( $options['USE INDEX'] ) && is_string( $options['USE INDEX'] ) ) {
1694 $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1698 if ( isset( $options['IGNORE INDEX'] ) && is_string( $options['IGNORE INDEX'] ) ) {
1699 $ignoreIndex = $this->ignoreIndexClause( $options['IGNORE INDEX'] );
1704 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1708 * Returns an optional GROUP BY with an optional HAVING
1710 * @param array $options Associative array of options
1712 * @see Database::select()
1715 protected function makeGroupByWithHaving( $options ) {
1717 if ( isset( $options['GROUP BY'] ) ) {
1718 $gb = is_array( $options['GROUP BY'] )
1719 ?
implode( ',', $options['GROUP BY'] )
1720 : $options['GROUP BY'];
1721 $sql .= ' GROUP BY ' . $gb;
1723 if ( isset( $options['HAVING'] ) ) {
1724 $having = is_array( $options['HAVING'] )
1725 ?
$this->makeList( $options['HAVING'], self
::LIST_AND
)
1726 : $options['HAVING'];
1727 $sql .= ' HAVING ' . $having;
1734 * Returns an optional ORDER BY
1736 * @param array $options Associative array of options
1738 * @see Database::select()
1741 protected function makeOrderBy( $options ) {
1742 if ( isset( $options['ORDER BY'] ) ) {
1743 $ob = is_array( $options['ORDER BY'] )
1744 ?
implode( ',', $options['ORDER BY'] )
1745 : $options['ORDER BY'];
1747 return ' ORDER BY ' . $ob;
1753 public function select(
1754 $table, $vars, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1756 $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
1758 return $this->query( $sql, $fname );
1761 public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__
,
1762 $options = [], $join_conds = []
1764 if ( is_array( $vars ) ) {
1765 $fields = implode( ',', $this->fieldNamesWithAlias( $vars ) );
1770 $options = (array)$options;
1771 $useIndexes = ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1772 ?
$options['USE INDEX']
1775 isset( $options['IGNORE INDEX'] ) &&
1776 is_array( $options['IGNORE INDEX'] )
1778 ?
$options['IGNORE INDEX']
1782 $this->selectOptionsIncludeLocking( $options ) &&
1783 $this->selectFieldsOrOptionsAggregate( $vars, $options )
1785 // Some DB types (postgres/oracle) disallow FOR UPDATE with aggregate
1786 // functions. Discourage use of such queries to encourage compatibility.
1788 $this->deprecationLogger
,
1789 __METHOD__
. ": aggregation used with a locking SELECT ($fname)."
1793 if ( is_array( $table ) ) {
1795 $this->tableNamesWithIndexClauseOrJOIN(
1796 $table, $useIndexes, $ignoreIndexes, $join_conds );
1797 } elseif ( $table != '' ) {
1799 $this->tableNamesWithIndexClauseOrJOIN(
1800 [ $table ], $useIndexes, $ignoreIndexes, [] );
1805 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ) =
1806 $this->makeSelectOptions( $options );
1808 if ( is_array( $conds ) ) {
1809 $conds = $this->makeList( $conds, self
::LIST_AND
);
1812 if ( $conds === null ||
$conds === false ) {
1813 $this->queryLogger
->warning(
1817 . ' with incorrect parameters: $conds must be a string or an array'
1822 if ( $conds === '' ||
$conds === '*' ) {
1823 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex $preLimitTail";
1824 } elseif ( is_string( $conds ) ) {
1825 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex " .
1826 "WHERE $conds $preLimitTail";
1828 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
1831 if ( isset( $options['LIMIT'] ) ) {
1832 $sql = $this->limitResult( $sql, $options['LIMIT'],
1833 $options['OFFSET'] ??
false );
1835 $sql = "$sql $postLimitTail";
1837 if ( isset( $options['EXPLAIN'] ) ) {
1838 $sql = 'EXPLAIN ' . $sql;
1844 public function selectRow( $table, $vars, $conds, $fname = __METHOD__
,
1845 $options = [], $join_conds = []
1847 $options = (array)$options;
1848 $options['LIMIT'] = 1;
1849 $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
1851 if ( $res === false ) {
1855 if ( !$this->numRows( $res ) ) {
1859 $obj = $this->fetchObject( $res );
1864 public function estimateRowCount(
1865 $table, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1867 $conds = $this->normalizeConditions( $conds, $fname );
1868 $column = $this->extractSingleFieldFromList( $var );
1869 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1870 $conds[] = "$column IS NOT NULL";
1873 $res = $this->select(
1874 $table, [ 'rowcount' => 'COUNT(*)' ], $conds, $fname, $options, $join_conds
1876 $row = $res ?
$this->fetchRow( $res ) : [];
1878 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1881 public function selectRowCount(
1882 $tables, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1884 $conds = $this->normalizeConditions( $conds, $fname );
1885 $column = $this->extractSingleFieldFromList( $var );
1886 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1887 $conds[] = "$column IS NOT NULL";
1890 $res = $this->select(
1892 'tmp_count' => $this->buildSelectSubquery(
1901 [ 'rowcount' => 'COUNT(*)' ],
1905 $row = $res ?
$this->fetchRow( $res ) : [];
1907 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1911 * @param string|array $options
1914 private function selectOptionsIncludeLocking( $options ) {
1915 $options = (array)$options;
1916 foreach ( [ 'FOR UPDATE', 'LOCK IN SHARE MODE' ] as $lock ) {
1917 if ( in_array( $lock, $options, true ) ) {
1926 * @param array|string $fields
1927 * @param array|string $options
1930 private function selectFieldsOrOptionsAggregate( $fields, $options ) {
1931 foreach ( (array)$options as $key => $value ) {
1932 if ( is_string( $key ) ) {
1933 if ( preg_match( '/^(?:GROUP BY|HAVING)$/i', $key ) ) {
1936 } elseif ( is_string( $value ) ) {
1937 if ( preg_match( '/^(?:DISTINCT|DISTINCTROW)$/i', $value ) ) {
1943 $regex = '/^(?:COUNT|MIN|MAX|SUM|GROUP_CONCAT|LISTAGG|ARRAY_AGG)\s*\\(/i';
1944 foreach ( (array)$fields as $field ) {
1945 if ( is_string( $field ) && preg_match( $regex, $field ) ) {
1954 * @param array|string $conds
1955 * @param string $fname
1958 final protected function normalizeConditions( $conds, $fname ) {
1959 if ( $conds === null ||
$conds === false ) {
1960 $this->queryLogger
->warning(
1964 . ' with incorrect parameters: $conds must be a string or an array'
1969 if ( !is_array( $conds ) ) {
1970 $conds = ( $conds === '' ) ?
[] : [ $conds ];
1977 * @param array|string $var Field parameter in the style of select()
1978 * @return string|null Column name or null; ignores aliases
1979 * @throws DBUnexpectedError Errors out if multiple columns are given
1981 final protected function extractSingleFieldFromList( $var ) {
1982 if ( is_array( $var ) ) {
1985 } elseif ( count( $var ) == 1 ) {
1986 $column = $var[0] ??
reset( $var );
1988 throw new DBUnexpectedError( $this, __METHOD__
. ': got multiple columns.' );
1997 public function lockForUpdate(
1998 $table, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
2000 if ( !$this->trxLevel
&& !$this->getFlag( self
::DBO_TRX
) ) {
2001 throw new DBUnexpectedError(
2003 __METHOD__
. ': no transaction is active nor is DBO_TRX set'
2007 $options = (array)$options;
2008 $options[] = 'FOR UPDATE';
2010 return $this->selectRowCount( $table, '*', $conds, $fname, $options, $join_conds );
2014 * Removes most variables from an SQL query and replaces them with X or N for numbers.
2015 * It's only slightly flawed. Don't use for anything important.
2017 * @param string $sql A SQL Query
2021 protected static function generalizeSQL( $sql ) {
2022 # This does the same as the regexp below would do, but in such a way
2023 # as to avoid crashing php on some large strings.
2024 # $sql = preg_replace( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql );
2026 $sql = str_replace( "\\\\", '', $sql );
2027 $sql = str_replace( "\\'", '', $sql );
2028 $sql = str_replace( "\\\"", '', $sql );
2029 $sql = preg_replace( "/'.*'/s", "'X'", $sql );
2030 $sql = preg_replace( '/".*"/s', "'X'", $sql );
2032 # All newlines, tabs, etc replaced by single space
2033 $sql = preg_replace( '/\s+/', ' ', $sql );
2036 # except the ones surrounded by characters, e.g. l10n
2037 $sql = preg_replace( '/-?\d+(,-?\d+)+/s', 'N,...,N', $sql );
2038 $sql = preg_replace( '/(?<![a-zA-Z])-?\d+(?![a-zA-Z])/s', 'N', $sql );
2043 public function fieldExists( $table, $field, $fname = __METHOD__
) {
2044 $info = $this->fieldInfo( $table, $field );
2049 public function indexExists( $table, $index, $fname = __METHOD__
) {
2050 if ( !$this->tableExists( $table ) ) {
2054 $info = $this->indexInfo( $table, $index, $fname );
2055 if ( is_null( $info ) ) {
2058 return $info !== false;
2062 abstract public function tableExists( $table, $fname = __METHOD__
);
2064 public function indexUnique( $table, $index ) {
2065 $indexInfo = $this->indexInfo( $table, $index );
2067 if ( !$indexInfo ) {
2071 return !$indexInfo[0]->Non_unique
;
2075 * Helper for Database::insert().
2077 * @param array $options
2080 protected function makeInsertOptions( $options ) {
2081 return implode( ' ', $options );
2084 public function insert( $table, $a, $fname = __METHOD__
, $options = [] ) {
2085 # No rows to insert, easy just return now
2086 if ( !count( $a ) ) {
2090 $table = $this->tableName( $table );
2092 if ( !is_array( $options ) ) {
2093 $options = [ $options ];
2096 $options = $this->makeInsertOptions( $options );
2098 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
2100 $keys = array_keys( $a[0] );
2103 $keys = array_keys( $a );
2106 $sql = 'INSERT ' . $options .
2107 " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
2111 foreach ( $a as $row ) {
2117 $sql .= '(' . $this->makeList( $row ) . ')';
2120 $sql .= '(' . $this->makeList( $a ) . ')';
2123 $this->query( $sql, $fname );
2129 * Make UPDATE options array for Database::makeUpdateOptions
2131 * @param array $options
2134 protected function makeUpdateOptionsArray( $options ) {
2135 if ( !is_array( $options ) ) {
2136 $options = [ $options ];
2141 if ( in_array( 'IGNORE', $options ) ) {
2149 * Make UPDATE options for the Database::update function
2151 * @param array $options The options passed to Database::update
2154 protected function makeUpdateOptions( $options ) {
2155 $opts = $this->makeUpdateOptionsArray( $options );
2157 return implode( ' ', $opts );
2160 public function update( $table, $values, $conds, $fname = __METHOD__
, $options = [] ) {
2161 $table = $this->tableName( $table );
2162 $opts = $this->makeUpdateOptions( $options );
2163 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, self
::LIST_SET
);
2165 if ( $conds !== [] && $conds !== '*' ) {
2166 $sql .= " WHERE " . $this->makeList( $conds, self
::LIST_AND
);
2169 $this->query( $sql, $fname );
2174 public function makeList( $a, $mode = self
::LIST_COMMA
) {
2175 if ( !is_array( $a ) ) {
2176 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
2182 foreach ( $a as $field => $value ) {
2184 if ( $mode == self
::LIST_AND
) {
2186 } elseif ( $mode == self
::LIST_OR
) {
2195 if ( ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_numeric( $field ) ) {
2196 $list .= "($value)";
2197 } elseif ( $mode == self
::LIST_SET
&& is_numeric( $field ) ) {
2200 ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_array( $value )
2202 // Remove null from array to be handled separately if found
2203 $includeNull = false;
2204 foreach ( array_keys( $value, null, true ) as $nullKey ) {
2205 $includeNull = true;
2206 unset( $value[$nullKey] );
2208 if ( count( $value ) == 0 && !$includeNull ) {
2209 throw new InvalidArgumentException(
2210 __METHOD__
. ": empty input for field $field" );
2211 } elseif ( count( $value ) == 0 ) {
2212 // only check if $field is null
2213 $list .= "$field IS NULL";
2215 // IN clause contains at least one valid element
2216 if ( $includeNull ) {
2217 // Group subconditions to ensure correct precedence
2220 if ( count( $value ) == 1 ) {
2221 // Special-case single values, as IN isn't terribly efficient
2222 // Don't necessarily assume the single key is 0; we don't
2223 // enforce linear numeric ordering on other arrays here.
2224 $value = array_values( $value )[0];
2225 $list .= $field . " = " . $this->addQuotes( $value );
2227 $list .= $field . " IN (" . $this->makeList( $value ) . ") ";
2229 // if null present in array, append IS NULL
2230 if ( $includeNull ) {
2231 $list .= " OR $field IS NULL)";
2234 } elseif ( $value === null ) {
2235 if ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) {
2236 $list .= "$field IS ";
2237 } elseif ( $mode == self
::LIST_SET
) {
2238 $list .= "$field = ";
2243 $mode == self
::LIST_AND ||
$mode == self
::LIST_OR ||
$mode == self
::LIST_SET
2245 $list .= "$field = ";
2247 $list .= $mode == self
::LIST_NAMES ?
$value : $this->addQuotes( $value );
2254 public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
2257 foreach ( $data as $base => $sub ) {
2258 if ( count( $sub ) ) {
2259 $conds[] = $this->makeList(
2260 [ $baseKey => $base, $subKey => array_keys( $sub ) ],
2266 return $this->makeList( $conds, self
::LIST_OR
);
2268 // Nothing to search for...
2273 public function aggregateValue( $valuedata, $valuename = 'value' ) {
2277 public function bitNot( $field ) {
2281 public function bitAnd( $fieldLeft, $fieldRight ) {
2282 return "($fieldLeft & $fieldRight)";
2285 public function bitOr( $fieldLeft, $fieldRight ) {
2286 return "($fieldLeft | $fieldRight)";
2289 public function buildConcat( $stringList ) {
2290 return 'CONCAT(' . implode( ',', $stringList ) . ')';
2293 public function buildGroupConcatField(
2294 $delim, $table, $field, $conds = '', $join_conds = []
2296 $fld = "GROUP_CONCAT($field SEPARATOR " . $this->addQuotes( $delim ) . ')';
2298 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
2301 public function buildSubstring( $input, $startPosition, $length = null ) {
2302 $this->assertBuildSubstringParams( $startPosition, $length );
2303 $functionBody = "$input FROM $startPosition";
2304 if ( $length !== null ) {
2305 $functionBody .= " FOR $length";
2307 return 'SUBSTRING(' . $functionBody . ')';
2311 * Check type and bounds for parameters to self::buildSubstring()
2313 * All supported databases have substring functions that behave the same for
2314 * positive $startPosition and non-negative $length, but behaviors differ when
2315 * given 0 or negative $startPosition or negative $length. The simplest
2316 * solution to that is to just forbid those values.
2318 * @param int $startPosition
2319 * @param int|null $length
2322 protected function assertBuildSubstringParams( $startPosition, $length ) {
2323 if ( !is_int( $startPosition ) ||
$startPosition <= 0 ) {
2324 throw new InvalidArgumentException(
2325 '$startPosition must be a positive integer'
2328 if ( !( is_int( $length ) && $length >= 0 ||
$length === null ) ) {
2329 throw new InvalidArgumentException(
2330 '$length must be null or an integer greater than or equal to 0'
2335 public function buildStringCast( $field ) {
2336 // In theory this should work for any standards-compliant
2337 // SQL implementation, although it may not be the best way to do it.
2338 return "CAST( $field AS CHARACTER )";
2341 public function buildIntegerCast( $field ) {
2342 return 'CAST( ' . $field . ' AS INTEGER )';
2345 public function buildSelectSubquery(
2346 $table, $vars, $conds = '', $fname = __METHOD__
,
2347 $options = [], $join_conds = []
2349 return new Subquery(
2350 $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds )
2354 public function databasesAreIndependent() {
2358 final public function selectDB( $db ) {
2359 $this->selectDomain( new DatabaseDomain(
2361 $this->currentDomain
->getSchema(),
2362 $this->currentDomain
->getTablePrefix()
2368 final public function selectDomain( $domain ) {
2369 $this->doSelectDomain( DatabaseDomain
::newFromId( $domain ) );
2372 protected function doSelectDomain( DatabaseDomain
$domain ) {
2373 $this->currentDomain
= $domain;
2376 public function getDBname() {
2377 return $this->currentDomain
->getDatabase();
2380 public function getServer() {
2381 return $this->server
;
2384 public function tableName( $name, $format = 'quoted' ) {
2385 if ( $name instanceof Subquery
) {
2386 throw new DBUnexpectedError(
2388 __METHOD__
. ': got Subquery instance when expecting a string.'
2392 # Skip the entire process when we have a string quoted on both ends.
2393 # Note that we check the end so that we will still quote any use of
2394 # use of `database`.table. But won't break things if someone wants
2395 # to query a database table with a dot in the name.
2396 if ( $this->isQuotedIdentifier( $name ) ) {
2400 # Lets test for any bits of text that should never show up in a table
2401 # name. Basically anything like JOIN or ON which are actually part of
2402 # SQL queries, but may end up inside of the table value to combine
2403 # sql. Such as how the API is doing.
2404 # Note that we use a whitespace test rather than a \b test to avoid
2405 # any remote case where a word like on may be inside of a table name
2406 # surrounded by symbols which may be considered word breaks.
2407 if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) {
2408 $this->queryLogger
->warning(
2409 __METHOD__
. ": use of subqueries is not supported this way.",
2410 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
2416 # Split database and table into proper variables.
2417 list( $database, $schema, $prefix, $table ) = $this->qualifiedTableComponents( $name );
2419 # Quote $table and apply the prefix if not quoted.
2420 # $tableName might be empty if this is called from Database::replaceVars()
2421 $tableName = "{$prefix}{$table}";
2422 if ( $format === 'quoted'
2423 && !$this->isQuotedIdentifier( $tableName )
2424 && $tableName !== ''
2426 $tableName = $this->addIdentifierQuotes( $tableName );
2429 # Quote $schema and $database and merge them with the table name if needed
2430 $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
2431 $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
2437 * Get the table components needed for a query given the currently selected database
2439 * @param string $name Table name in the form of db.schema.table, db.table, or table
2440 * @return array (DB name or "" for default, schema name, table prefix, table name)
2442 protected function qualifiedTableComponents( $name ) {
2443 # We reverse the explode so that database.table and table both output the correct table.
2444 $dbDetails = explode( '.', $name, 3 );
2445 if ( count( $dbDetails ) == 3 ) {
2446 list( $database, $schema, $table ) = $dbDetails;
2447 # We don't want any prefix added in this case
2449 } elseif ( count( $dbDetails ) == 2 ) {
2450 list( $database, $table ) = $dbDetails;
2451 # We don't want any prefix added in this case
2453 # In dbs that support it, $database may actually be the schema
2454 # but that doesn't affect any of the functionality here
2457 list( $table ) = $dbDetails;
2458 if ( isset( $this->tableAliases
[$table] ) ) {
2459 $database = $this->tableAliases
[$table]['dbname'];
2460 $schema = is_string( $this->tableAliases
[$table]['schema'] )
2461 ?
$this->tableAliases
[$table]['schema']
2462 : $this->relationSchemaQualifier();
2463 $prefix = is_string( $this->tableAliases
[$table]['prefix'] )
2464 ?
$this->tableAliases
[$table]['prefix']
2465 : $this->tablePrefix();
2468 $schema = $this->relationSchemaQualifier(); # Default schema
2469 $prefix = $this->tablePrefix(); # Default prefix
2473 return [ $database, $schema, $prefix, $table ];
2477 * @param string|null $namespace Database or schema
2478 * @param string $relation Name of table, view, sequence, etc...
2479 * @param string $format One of (raw, quoted)
2480 * @return string Relation name with quoted and merged $namespace as needed
2482 private function prependDatabaseOrSchema( $namespace, $relation, $format ) {
2483 if ( strlen( $namespace ) ) {
2484 if ( $format === 'quoted' && !$this->isQuotedIdentifier( $namespace ) ) {
2485 $namespace = $this->addIdentifierQuotes( $namespace );
2487 $relation = $namespace . '.' . $relation;
2493 public function tableNames() {
2494 $inArray = func_get_args();
2497 foreach ( $inArray as $name ) {
2498 $retVal[$name] = $this->tableName( $name );
2504 public function tableNamesN() {
2505 $inArray = func_get_args();
2508 foreach ( $inArray as $name ) {
2509 $retVal[] = $this->tableName( $name );
2516 * Get an aliased table name
2518 * This returns strings like "tableName AS newTableName" for aliased tables
2519 * and "(SELECT * from tableA) newTablename" for subqueries (e.g. derived tables)
2521 * @see Database::tableName()
2522 * @param string|Subquery $table Table name or object with a 'sql' field
2523 * @param string|bool $alias Table alias (optional)
2524 * @return string SQL name for aliased table. Will not alias a table to its own name
2526 protected function tableNameWithAlias( $table, $alias = false ) {
2527 if ( is_string( $table ) ) {
2528 $quotedTable = $this->tableName( $table );
2529 } elseif ( $table instanceof Subquery
) {
2530 $quotedTable = (string)$table;
2532 throw new InvalidArgumentException( "Table must be a string or Subquery." );
2535 if ( !strlen( $alias ) ||
$alias === $table ) {
2536 if ( $table instanceof Subquery
) {
2537 throw new InvalidArgumentException( "Subquery table missing alias." );
2540 return $quotedTable;
2542 return $quotedTable . ' ' . $this->addIdentifierQuotes( $alias );
2547 * Gets an array of aliased table names
2549 * @param array $tables [ [alias] => table ]
2550 * @return string[] See tableNameWithAlias()
2552 protected function tableNamesWithAlias( $tables ) {
2554 foreach ( $tables as $alias => $table ) {
2555 if ( is_numeric( $alias ) ) {
2558 $retval[] = $this->tableNameWithAlias( $table, $alias );
2565 * Get an aliased field name
2566 * e.g. fieldName AS newFieldName
2568 * @param string $name Field name
2569 * @param string|bool $alias Alias (optional)
2570 * @return string SQL name for aliased field. Will not alias a field to its own name
2572 protected function fieldNameWithAlias( $name, $alias = false ) {
2573 if ( !$alias ||
(string)$alias === (string)$name ) {
2576 return $name . ' AS ' . $this->addIdentifierQuotes( $alias ); // PostgreSQL needs AS
2581 * Gets an array of aliased field names
2583 * @param array $fields [ [alias] => field ]
2584 * @return string[] See fieldNameWithAlias()
2586 protected function fieldNamesWithAlias( $fields ) {
2588 foreach ( $fields as $alias => $field ) {
2589 if ( is_numeric( $alias ) ) {
2592 $retval[] = $this->fieldNameWithAlias( $field, $alias );
2599 * Get the aliased table name clause for a FROM clause
2600 * which might have a JOIN and/or USE INDEX or IGNORE INDEX clause
2602 * @param array $tables ( [alias] => table )
2603 * @param array $use_index Same as for select()
2604 * @param array $ignore_index Same as for select()
2605 * @param array $join_conds Same as for select()
2608 protected function tableNamesWithIndexClauseOrJOIN(
2609 $tables, $use_index = [], $ignore_index = [], $join_conds = []
2613 $use_index = (array)$use_index;
2614 $ignore_index = (array)$ignore_index;
2615 $join_conds = (array)$join_conds;
2617 foreach ( $tables as $alias => $table ) {
2618 if ( !is_string( $alias ) ) {
2619 // No alias? Set it equal to the table name
2623 if ( is_array( $table ) ) {
2624 // A parenthesized group
2625 if ( count( $table ) > 1 ) {
2626 $joinedTable = '(' .
2627 $this->tableNamesWithIndexClauseOrJOIN(
2628 $table, $use_index, $ignore_index, $join_conds ) . ')';
2631 $innerTable = reset( $table );
2632 $innerAlias = key( $table );
2633 $joinedTable = $this->tableNameWithAlias(
2635 is_string( $innerAlias ) ?
$innerAlias : $innerTable
2639 $joinedTable = $this->tableNameWithAlias( $table, $alias );
2642 // Is there a JOIN clause for this table?
2643 if ( isset( $join_conds[$alias] ) ) {
2644 list( $joinType, $conds ) = $join_conds[$alias];
2645 $tableClause = $joinType;
2646 $tableClause .= ' ' . $joinedTable;
2647 if ( isset( $use_index[$alias] ) ) { // has USE INDEX?
2648 $use = $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) );
2650 $tableClause .= ' ' . $use;
2653 if ( isset( $ignore_index[$alias] ) ) { // has IGNORE INDEX?
2654 $ignore = $this->ignoreIndexClause(
2655 implode( ',', (array)$ignore_index[$alias] ) );
2656 if ( $ignore != '' ) {
2657 $tableClause .= ' ' . $ignore;
2660 $on = $this->makeList( (array)$conds, self
::LIST_AND
);
2662 $tableClause .= ' ON (' . $on . ')';
2665 $retJOIN[] = $tableClause;
2666 } elseif ( isset( $use_index[$alias] ) ) {
2667 // Is there an INDEX clause for this table?
2668 $tableClause = $joinedTable;
2669 $tableClause .= ' ' . $this->useIndexClause(
2670 implode( ',', (array)$use_index[$alias] )
2673 $ret[] = $tableClause;
2674 } elseif ( isset( $ignore_index[$alias] ) ) {
2675 // Is there an INDEX clause for this table?
2676 $tableClause = $joinedTable;
2677 $tableClause .= ' ' . $this->ignoreIndexClause(
2678 implode( ',', (array)$ignore_index[$alias] )
2681 $ret[] = $tableClause;
2683 $tableClause = $joinedTable;
2685 $ret[] = $tableClause;
2689 // We can't separate explicit JOIN clauses with ',', use ' ' for those
2690 $implicitJoins = $ret ?
implode( ',', $ret ) : "";
2691 $explicitJoins = $retJOIN ?
implode( ' ', $retJOIN ) : "";
2693 // Compile our final table clause
2694 return implode( ' ', [ $implicitJoins, $explicitJoins ] );
2698 * Allows for index remapping in queries where this is not consistent across DBMS
2700 * @param string $index
2703 protected function indexName( $index ) {
2704 return $this->indexAliases
[$index] ??
$index;
2707 public function addQuotes( $s ) {
2708 if ( $s instanceof Blob
) {
2711 if ( $s === null ) {
2713 } elseif ( is_bool( $s ) ) {
2716 # This will also quote numeric values. This should be harmless,
2717 # and protects against weird problems that occur when they really
2718 # _are_ strings such as article titles and string->number->string
2719 # conversion is not 1:1.
2720 return "'" . $this->strencode( $s ) . "'";
2724 public function addIdentifierQuotes( $s ) {
2725 return '"' . str_replace( '"', '""', $s ) . '"';
2729 * Returns if the given identifier looks quoted or not according to
2730 * the database convention for quoting identifiers .
2732 * @note Do not use this to determine if untrusted input is safe.
2733 * A malicious user can trick this function.
2734 * @param string $name
2737 public function isQuotedIdentifier( $name ) {
2738 return $name[0] == '"' && substr( $name, -1, 1 ) == '"';
2743 * @param string $escapeChar
2746 protected function escapeLikeInternal( $s, $escapeChar = '`' ) {
2747 return str_replace( [ $escapeChar, '%', '_' ],
2748 [ "{$escapeChar}{$escapeChar}", "{$escapeChar}%", "{$escapeChar}_" ],
2752 public function buildLike() {
2753 $params = func_get_args();
2755 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
2756 $params = $params[0];
2761 // We use ` instead of \ as the default LIKE escape character, since addQuotes()
2762 // may escape backslashes, creating problems of double escaping. The `
2763 // character has good cross-DBMS compatibility, avoiding special operators
2764 // in MS SQL like ^ and %
2767 foreach ( $params as $value ) {
2768 if ( $value instanceof LikeMatch
) {
2769 $s .= $value->toString();
2771 $s .= $this->escapeLikeInternal( $value, $escapeChar );
2776 $this->addQuotes( $s ) . ' ESCAPE ' . $this->addQuotes( $escapeChar ) . ' ';
2779 public function anyChar() {
2780 return new LikeMatch( '_' );
2783 public function anyString() {
2784 return new LikeMatch( '%' );
2787 public function nextSequenceValue( $seqName ) {
2792 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
2793 * is only needed because a) MySQL must be as efficient as possible due to
2794 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2795 * which index to pick. Anyway, other databases might have different
2796 * indexes on a given table. So don't bother overriding this unless you're
2798 * @param string $index
2801 public function useIndexClause( $index ) {
2806 * IGNORE INDEX clause. Unlikely to be useful for anything but MySQL. This
2807 * is only needed because a) MySQL must be as efficient as possible due to
2808 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2809 * which index to pick. Anyway, other databases might have different
2810 * indexes on a given table. So don't bother overriding this unless you're
2812 * @param string $index
2815 public function ignoreIndexClause( $index ) {
2819 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__
) {
2820 if ( count( $rows ) == 0 ) {
2824 $uniqueIndexes = (array)$uniqueIndexes;
2826 if ( !is_array( reset( $rows ) ) ) {
2831 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2832 $affectedRowCount = 0;
2833 foreach ( $rows as $row ) {
2834 // Delete rows which collide with this one
2835 $indexWhereClauses = [];
2836 foreach ( $uniqueIndexes as $index ) {
2837 $indexColumns = (array)$index;
2838 $indexRowValues = array_intersect_key( $row, array_flip( $indexColumns ) );
2839 if ( count( $indexRowValues ) != count( $indexColumns ) ) {
2840 throw new DBUnexpectedError(
2842 'New record does not provide all values for unique key (' .
2843 implode( ', ', $indexColumns ) . ')'
2845 } elseif ( in_array( null, $indexRowValues, true ) ) {
2846 throw new DBUnexpectedError(
2848 'New record has a null value for unique key (' .
2849 implode( ', ', $indexColumns ) . ')'
2852 $indexWhereClauses[] = $this->makeList( $indexRowValues, LIST_AND
);
2855 if ( $indexWhereClauses ) {
2856 $this->delete( $table, $this->makeList( $indexWhereClauses, LIST_OR
), $fname );
2857 $affectedRowCount +
= $this->affectedRows();
2860 // Now insert the row
2861 $this->insert( $table, $row, $fname );
2862 $affectedRowCount +
= $this->affectedRows();
2864 $this->endAtomic( $fname );
2865 $this->affectedRowCount
= $affectedRowCount;
2866 } catch ( Exception
$e ) {
2867 $this->cancelAtomic( $fname );
2873 * REPLACE query wrapper for MySQL and SQLite, which have a native REPLACE
2876 * @param string $table Table name
2877 * @param array|string $rows Row(s) to insert
2878 * @param string $fname Caller function name
2880 protected function nativeReplace( $table, $rows, $fname ) {
2881 $table = $this->tableName( $table );
2884 if ( !is_array( reset( $rows ) ) ) {
2888 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES ';
2891 foreach ( $rows as $row ) {
2898 $sql .= '(' . $this->makeList( $row ) . ')';
2901 $this->query( $sql, $fname );
2904 public function upsert( $table, array $rows, $uniqueIndexes, array $set,
2907 if ( $rows === [] ) {
2908 return true; // nothing to do
2911 $uniqueIndexes = (array)$uniqueIndexes;
2912 if ( !is_array( reset( $rows ) ) ) {
2916 if ( count( $uniqueIndexes ) ) {
2917 $clauses = []; // list WHERE clauses that each identify a single row
2918 foreach ( $rows as $row ) {
2919 foreach ( $uniqueIndexes as $index ) {
2920 $index = is_array( $index ) ?
$index : [ $index ]; // columns
2921 $rowKey = []; // unique key to this row
2922 foreach ( $index as $column ) {
2923 $rowKey[$column] = $row[$column];
2925 $clauses[] = $this->makeList( $rowKey, self
::LIST_AND
);
2928 $where = [ $this->makeList( $clauses, self
::LIST_OR
) ];
2933 $affectedRowCount = 0;
2935 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2936 # Update any existing conflicting row(s)
2937 if ( $where !== false ) {
2938 $this->update( $table, $set, $where, $fname );
2939 $affectedRowCount +
= $this->affectedRows();
2941 # Now insert any non-conflicting row(s)
2942 $this->insert( $table, $rows, $fname, [ 'IGNORE' ] );
2943 $affectedRowCount +
= $this->affectedRows();
2944 $this->endAtomic( $fname );
2945 $this->affectedRowCount
= $affectedRowCount;
2946 } catch ( Exception
$e ) {
2947 $this->cancelAtomic( $fname );
2954 public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
2958 throw new DBUnexpectedError( $this, __METHOD__
. ' called with empty $conds' );
2961 $delTable = $this->tableName( $delTable );
2962 $joinTable = $this->tableName( $joinTable );
2963 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
2964 if ( $conds != '*' ) {
2965 $sql .= 'WHERE ' . $this->makeList( $conds, self
::LIST_AND
);
2969 $this->query( $sql, $fname );
2972 public function textFieldSize( $table, $field ) {
2973 $table = $this->tableName( $table );
2974 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
2975 $res = $this->query( $sql, __METHOD__
);
2976 $row = $this->fetchObject( $res );
2980 if ( preg_match( '/\((.*)\)/', $row->Type
, $m ) ) {
2989 public function delete( $table, $conds, $fname = __METHOD__
) {
2991 throw new DBUnexpectedError( $this, __METHOD__
. ' called with no conditions' );
2994 $table = $this->tableName( $table );
2995 $sql = "DELETE FROM $table";
2997 if ( $conds != '*' ) {
2998 if ( is_array( $conds ) ) {
2999 $conds = $this->makeList( $conds, self
::LIST_AND
);
3001 $sql .= ' WHERE ' . $conds;
3004 $this->query( $sql, $fname );
3009 final public function insertSelect(
3010 $destTable, $srcTable, $varMap, $conds,
3011 $fname = __METHOD__
, $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3013 static $hints = [ 'NO_AUTO_COLUMNS' ];
3015 $insertOptions = (array)$insertOptions;
3016 $selectOptions = (array)$selectOptions;
3018 if ( $this->cliMode
&& $this->isInsertSelectSafe( $insertOptions, $selectOptions ) ) {
3019 // For massive migrations with downtime, we don't want to select everything
3020 // into memory and OOM, so do all this native on the server side if possible.
3021 $this->nativeInsertSelect(
3027 array_diff( $insertOptions, $hints ),
3032 $this->nonNativeInsertSelect(
3038 array_diff( $insertOptions, $hints ),
3048 * @param array $insertOptions INSERT options
3049 * @param array $selectOptions SELECT options
3050 * @return bool Whether an INSERT SELECT with these options will be replication safe
3053 protected function isInsertSelectSafe( array $insertOptions, array $selectOptions ) {
3058 * Implementation of insertSelect() based on select() and insert()
3060 * @see IDatabase::insertSelect()
3062 * @param string $destTable
3063 * @param string|array $srcTable
3064 * @param array $varMap
3065 * @param array $conds
3066 * @param string $fname
3067 * @param array $insertOptions
3068 * @param array $selectOptions
3069 * @param array $selectJoinConds
3071 protected function nonNativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3072 $fname = __METHOD__
,
3073 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3075 // For web requests, do a locking SELECT and then INSERT. This puts the SELECT burden
3076 // on only the master (without needing row-based-replication). It also makes it easy to
3077 // know how big the INSERT is going to be.
3079 foreach ( $varMap as $dstColumn => $sourceColumnOrSql ) {
3080 $fields[] = $this->fieldNameWithAlias( $sourceColumnOrSql, $dstColumn );
3082 $selectOptions[] = 'FOR UPDATE';
3083 $res = $this->select(
3084 $srcTable, implode( ',', $fields ), $conds, $fname, $selectOptions, $selectJoinConds
3091 $affectedRowCount = 0;
3092 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
3095 foreach ( $res as $row ) {
3096 $rows[] = (array)$row;
3098 // Avoid inserts that are too huge
3099 if ( count( $rows ) >= $this->nonNativeInsertSelectBatchSize
) {
3100 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
3104 $affectedRowCount +
= $this->affectedRows();
3108 if ( $rows && $ok ) {
3109 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
3111 $affectedRowCount +
= $this->affectedRows();
3115 $this->endAtomic( $fname );
3116 $this->affectedRowCount
= $affectedRowCount;
3118 $this->cancelAtomic( $fname );
3120 } catch ( Exception
$e ) {
3121 $this->cancelAtomic( $fname );
3127 * Native server-side implementation of insertSelect() for situations where
3128 * we don't want to select everything into memory
3130 * @see IDatabase::insertSelect()
3131 * @param string $destTable
3132 * @param string|array $srcTable
3133 * @param array $varMap
3134 * @param array $conds
3135 * @param string $fname
3136 * @param array $insertOptions
3137 * @param array $selectOptions
3138 * @param array $selectJoinConds
3140 protected function nativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3141 $fname = __METHOD__
,
3142 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3144 $destTable = $this->tableName( $destTable );
3146 if ( !is_array( $insertOptions ) ) {
3147 $insertOptions = [ $insertOptions ];
3150 $insertOptions = $this->makeInsertOptions( $insertOptions );
3152 $selectSql = $this->selectSQLText(
3154 array_values( $varMap ),
3161 $sql = "INSERT $insertOptions" .
3162 " INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ') ' .
3165 $this->query( $sql, $fname );
3169 * Construct a LIMIT query with optional offset. This is used for query
3170 * pages. The SQL should be adjusted so that only the first $limit rows
3171 * are returned. If $offset is provided as well, then the first $offset
3172 * rows should be discarded, and the next $limit rows should be returned.
3173 * If the result of the query is not ordered, then the rows to be returned
3174 * are theoretically arbitrary.
3176 * $sql is expected to be a SELECT, if that makes a difference.
3178 * The version provided by default works in MySQL and SQLite. It will very
3179 * likely need to be overridden for most other DBMSes.
3181 * @param string $sql SQL query we will append the limit too
3182 * @param int $limit The SQL limit
3183 * @param int|bool $offset The SQL offset (default false)
3184 * @throws DBUnexpectedError
3187 public function limitResult( $sql, $limit, $offset = false ) {
3188 if ( !is_numeric( $limit ) ) {
3189 throw new DBUnexpectedError( $this,
3190 "Invalid non-numeric limit passed to limitResult()\n" );
3193 return "$sql LIMIT "
3194 . ( ( is_numeric( $offset ) && $offset != 0 ) ?
"{$offset}," : "" )
3198 public function unionSupportsOrderAndLimit() {
3199 return true; // True for almost every DB supported
3202 public function unionQueries( $sqls, $all ) {
3203 $glue = $all ?
') UNION ALL (' : ') UNION (';
3205 return '(' . implode( $glue, $sqls ) . ')';
3208 public function unionConditionPermutations(
3209 $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__
,
3210 $options = [], $join_conds = []
3212 // First, build the Cartesian product of $permute_conds
3214 foreach ( $permute_conds as $field => $values ) {
3216 // Skip empty $values
3219 $values = array_unique( $values ); // For sanity
3221 foreach ( $conds as $cond ) {
3222 foreach ( $values as $value ) {
3223 $cond[$field] = $value;
3224 $newConds[] = $cond; // Arrays are by-value, not by-reference, so this works
3230 $extra_conds = $extra_conds === '' ?
[] : (array)$extra_conds;
3232 // If there's just one condition and no subordering, hand off to
3233 // selectSQLText directly.
3234 if ( count( $conds ) === 1 &&
3235 ( !isset( $options['INNER ORDER BY'] ) ||
!$this->unionSupportsOrderAndLimit() )
3237 return $this->selectSQLText(
3238 $table, $vars, $conds[0] +
$extra_conds, $fname, $options, $join_conds
3242 // Otherwise, we need to pull out the order and limit to apply after
3243 // the union. Then build the SQL queries for each set of conditions in
3244 // $conds. Then union them together (using UNION ALL, because the
3245 // product *should* already be distinct).
3246 $orderBy = $this->makeOrderBy( $options );
3247 $limit = $options['LIMIT'] ??
null;
3248 $offset = $options['OFFSET'] ??
false;
3249 $all = empty( $options['NOTALL'] ) && !in_array( 'NOTALL', $options );
3250 if ( !$this->unionSupportsOrderAndLimit() ) {
3251 unset( $options['ORDER BY'], $options['LIMIT'], $options['OFFSET'] );
3253 if ( array_key_exists( 'INNER ORDER BY', $options ) ) {
3254 $options['ORDER BY'] = $options['INNER ORDER BY'];
3256 if ( $limit !== null && is_numeric( $offset ) && $offset != 0 ) {
3257 // We need to increase the limit by the offset rather than
3258 // using the offset directly, otherwise it'll skip incorrectly
3259 // in the subqueries.
3260 $options['LIMIT'] = $limit +
$offset;
3261 unset( $options['OFFSET'] );
3266 foreach ( $conds as $cond ) {
3267 $sqls[] = $this->selectSQLText(
3268 $table, $vars, $cond +
$extra_conds, $fname, $options, $join_conds
3271 $sql = $this->unionQueries( $sqls, $all ) . $orderBy;
3272 if ( $limit !== null ) {
3273 $sql = $this->limitResult( $sql, $limit, $offset );
3279 public function conditional( $cond, $trueVal, $falseVal ) {
3280 if ( is_array( $cond ) ) {
3281 $cond = $this->makeList( $cond, self
::LIST_AND
);
3284 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
3287 public function strreplace( $orig, $old, $new ) {
3288 return "REPLACE({$orig}, {$old}, {$new})";
3291 public function getServerUptime() {
3295 public function wasDeadlock() {
3299 public function wasLockTimeout() {
3303 public function wasConnectionLoss() {
3304 return $this->wasConnectionError( $this->lastErrno() );
3307 public function wasReadOnlyError() {
3311 public function wasErrorReissuable() {
3313 $this->wasDeadlock() ||
3314 $this->wasLockTimeout() ||
3315 $this->wasConnectionLoss()
3320 * Do not use this method outside of Database/DBError classes
3322 * @param int|string $errno
3323 * @return bool Whether the given query error was a connection drop
3325 public function wasConnectionError( $errno ) {
3330 * @return bool Whether it is known that the last query error only caused statement rollback
3331 * @note This is for backwards compatibility for callers catching DBError exceptions in
3332 * order to ignore problems like duplicate key errors or foriegn key violations
3335 protected function wasKnownStatementRollbackError() {
3336 return false; // don't know; it could have caused a transaction rollback
3339 public function deadlockLoop() {
3340 $args = func_get_args();
3341 $function = array_shift( $args );
3342 $tries = self
::DEADLOCK_TRIES
;
3344 $this->begin( __METHOD__
);
3347 /** @var Exception $e */
3351 $retVal = $function( ...$args );
3353 } catch ( DBQueryError
$e ) {
3354 if ( $this->wasDeadlock() ) {
3355 // Retry after a randomized delay
3356 usleep( mt_rand( self
::DEADLOCK_DELAY_MIN
, self
::DEADLOCK_DELAY_MAX
) );
3358 // Throw the error back up
3362 } while ( --$tries > 0 );
3364 if ( $tries <= 0 ) {
3365 // Too many deadlocks; give up
3366 $this->rollback( __METHOD__
);
3369 $this->commit( __METHOD__
);
3375 public function masterPosWait( DBMasterPos
$pos, $timeout ) {
3376 # Real waits are implemented in the subclass.
3380 public function getReplicaPos() {
3385 public function getMasterPos() {
3390 public function serverIsReadOnly() {
3394 final public function onTransactionResolution( callable
$callback, $fname = __METHOD__
) {
3395 if ( !$this->trxLevel
) {
3396 throw new DBUnexpectedError( $this, "No transaction is active." );
3398 $this->trxEndCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3401 final public function onTransactionCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3402 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3403 // Start an implicit transaction similar to how query() does
3404 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3405 $this->trxAutomatic
= true;
3408 $this->trxIdleCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3409 if ( !$this->trxLevel
) {
3410 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_IDLE
);
3414 final public function onTransactionIdle( callable
$callback, $fname = __METHOD__
) {
3415 $this->onTransactionCommitOrIdle( $callback, $fname );
3418 final public function onTransactionPreCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3419 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3420 // Start an implicit transaction similar to how query() does
3421 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3422 $this->trxAutomatic
= true;
3425 if ( $this->trxLevel
) {
3426 $this->trxPreCommitCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3428 // No transaction is active nor will start implicitly, so make one for this callback
3429 $this->startAtomic( __METHOD__
, self
::ATOMIC_CANCELABLE
);
3432 $this->endAtomic( __METHOD__
);
3433 } catch ( Exception
$e ) {
3434 $this->cancelAtomic( __METHOD__
);
3441 * @return AtomicSectionIdentifier|null ID of the topmost atomic section level
3443 private function currentAtomicSectionId() {
3444 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3445 $levelInfo = end( $this->trxAtomicLevels
);
3447 return $levelInfo[1];
3454 * @param AtomicSectionIdentifier $old
3455 * @param AtomicSectionIdentifier $new
3457 private function reassignCallbacksForSection(
3458 AtomicSectionIdentifier
$old, AtomicSectionIdentifier
$new
3460 foreach ( $this->trxPreCommitCallbacks
as $key => $info ) {
3461 if ( $info[2] === $old ) {
3462 $this->trxPreCommitCallbacks
[$key][2] = $new;
3465 foreach ( $this->trxIdleCallbacks
as $key => $info ) {
3466 if ( $info[2] === $old ) {
3467 $this->trxIdleCallbacks
[$key][2] = $new;
3470 foreach ( $this->trxEndCallbacks
as $key => $info ) {
3471 if ( $info[2] === $old ) {
3472 $this->trxEndCallbacks
[$key][2] = $new;
3478 * @param AtomicSectionIdentifier[] $sectionIds ID of an actual savepoint
3479 * @throws UnexpectedValueException
3481 private function modifyCallbacksForCancel( array $sectionIds ) {
3482 // Cancel the "on commit" callbacks owned by this savepoint
3483 $this->trxIdleCallbacks
= array_filter(
3484 $this->trxIdleCallbacks
,
3485 function ( $entry ) use ( $sectionIds ) {
3486 return !in_array( $entry[2], $sectionIds, true );
3489 $this->trxPreCommitCallbacks
= array_filter(
3490 $this->trxPreCommitCallbacks
,
3491 function ( $entry ) use ( $sectionIds ) {
3492 return !in_array( $entry[2], $sectionIds, true );
3495 // Make "on resolution" callbacks owned by this savepoint to perceive a rollback
3496 foreach ( $this->trxEndCallbacks
as $key => $entry ) {
3497 if ( in_array( $entry[2], $sectionIds, true ) ) {
3498 $callback = $entry[0];
3499 $this->trxEndCallbacks
[$key][0] = function () use ( $callback ) {
3500 return $callback( self
::TRIGGER_ROLLBACK
, $this );
3506 final public function setTransactionListener( $name, callable
$callback = null ) {
3508 $this->trxRecurringCallbacks
[$name] = $callback;
3510 unset( $this->trxRecurringCallbacks
[$name] );
3515 * Whether to disable running of post-COMMIT/ROLLBACK callbacks
3517 * This method should not be used outside of Database/LoadBalancer
3519 * @param bool $suppress
3522 final public function setTrxEndCallbackSuppression( $suppress ) {
3523 $this->trxEndCallbacksSuppressed
= $suppress;
3527 * Actually consume and run any "on transaction idle/resolution" callbacks.
3529 * This method should not be used outside of Database/LoadBalancer
3531 * @param int $trigger IDatabase::TRIGGER_* constant
3532 * @return int Number of callbacks attempted
3536 public function runOnTransactionIdleCallbacks( $trigger ) {
3537 if ( $this->trxLevel
) { // sanity
3538 throw new DBUnexpectedError( $this, __METHOD__
. ': a transaction is still open.' );
3541 if ( $this->trxEndCallbacksSuppressed
) {
3546 $autoTrx = $this->getFlag( self
::DBO_TRX
); // automatic begin() enabled?
3547 /** @var Exception $e */
3548 $e = null; // first exception
3549 do { // callbacks may add callbacks :)
3550 $callbacks = array_merge(
3551 $this->trxIdleCallbacks
,
3552 $this->trxEndCallbacks
// include "transaction resolution" callbacks
3554 $this->trxIdleCallbacks
= []; // consumed (and recursion guard)
3555 $this->trxEndCallbacks
= []; // consumed (recursion guard)
3556 foreach ( $callbacks as $callback ) {
3558 list( $phpCallback ) = $callback;
3559 $this->clearFlag( self
::DBO_TRX
); // make each query its own transaction
3561 call_user_func( $phpCallback, $trigger, $this );
3562 } catch ( Exception
$ex ) {
3563 call_user_func( $this->errorLogger
, $ex );
3565 // Some callbacks may use startAtomic/endAtomic, so make sure
3566 // their transactions are ended so other callbacks don't fail
3567 if ( $this->trxLevel() ) {
3568 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
3572 $this->setFlag( self
::DBO_TRX
); // restore automatic begin()
3574 $this->clearFlag( self
::DBO_TRX
); // restore auto-commit
3578 } while ( count( $this->trxIdleCallbacks
) );
3580 if ( $e instanceof Exception
) {
3581 throw $e; // re-throw any first exception
3588 * Actually consume and run any "on transaction pre-commit" callbacks.
3590 * This method should not be used outside of Database/LoadBalancer
3593 * @return int Number of callbacks attempted
3596 public function runOnTransactionPreCommitCallbacks() {
3599 $e = null; // first exception
3600 do { // callbacks may add callbacks :)
3601 $callbacks = $this->trxPreCommitCallbacks
;
3602 $this->trxPreCommitCallbacks
= []; // consumed (and recursion guard)
3603 foreach ( $callbacks as $callback ) {
3606 list( $phpCallback ) = $callback;
3607 $phpCallback( $this );
3608 } catch ( Exception
$ex ) {
3609 ( $this->errorLogger
)( $ex );
3613 } while ( count( $this->trxPreCommitCallbacks
) );
3615 if ( $e instanceof Exception
) {
3616 throw $e; // re-throw any first exception
3623 * Actually run any "transaction listener" callbacks.
3625 * This method should not be used outside of Database/LoadBalancer
3627 * @param int $trigger IDatabase::TRIGGER_* constant
3631 public function runTransactionListenerCallbacks( $trigger ) {
3632 if ( $this->trxEndCallbacksSuppressed
) {
3636 /** @var Exception $e */
3637 $e = null; // first exception
3639 foreach ( $this->trxRecurringCallbacks
as $phpCallback ) {
3641 $phpCallback( $trigger, $this );
3642 } catch ( Exception
$ex ) {
3643 ( $this->errorLogger
)( $ex );
3648 if ( $e instanceof Exception
) {
3649 throw $e; // re-throw any first exception
3654 * Create a savepoint
3656 * This is used internally to implement atomic sections. It should not be
3660 * @param string $identifier Identifier for the savepoint
3661 * @param string $fname Calling function name
3663 protected function doSavepoint( $identifier, $fname ) {
3664 $this->query( 'SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3668 * Release a savepoint
3670 * This is used internally to implement atomic sections. It should not be
3674 * @param string $identifier Identifier for the savepoint
3675 * @param string $fname Calling function name
3677 protected function doReleaseSavepoint( $identifier, $fname ) {
3678 $this->query( 'RELEASE SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3682 * Rollback to a savepoint
3684 * This is used internally to implement atomic sections. It should not be
3688 * @param string $identifier Identifier for the savepoint
3689 * @param string $fname Calling function name
3691 protected function doRollbackToSavepoint( $identifier, $fname ) {
3692 $this->query( 'ROLLBACK TO SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3696 * @param string $fname
3699 private function nextSavepointId( $fname ) {
3700 $savepointId = self
::$SAVEPOINT_PREFIX . ++
$this->trxAtomicCounter
;
3701 if ( strlen( $savepointId ) > 30 ) {
3702 // 30 == Oracle's identifier length limit (pre 12c)
3703 // With a 22 character prefix, that puts the highest number at 99999999.
3704 throw new DBUnexpectedError(
3706 'There have been an excessively large number of atomic sections in a transaction'
3707 . " started by $this->trxFname (at $fname)"
3711 return $savepointId;
3714 final public function startAtomic(
3715 $fname = __METHOD__
, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3717 $savepointId = $cancelable === self
::ATOMIC_CANCELABLE ? self
::$NOT_APPLICABLE : null;
3719 if ( !$this->trxLevel
) {
3720 $this->begin( $fname, self
::TRANSACTION_INTERNAL
); // sets trxAutomatic
3721 // If DBO_TRX is set, a series of startAtomic/endAtomic pairs will result
3722 // in all changes being in one transaction to keep requests transactional.
3723 if ( $this->getFlag( self
::DBO_TRX
) ) {
3724 // Since writes could happen in between the topmost atomic sections as part
3725 // of the transaction, those sections will need savepoints.
3726 $savepointId = $this->nextSavepointId( $fname );
3727 $this->doSavepoint( $savepointId, $fname );
3729 $this->trxAutomaticAtomic
= true;
3731 } elseif ( $cancelable === self
::ATOMIC_CANCELABLE
) {
3732 $savepointId = $this->nextSavepointId( $fname );
3733 $this->doSavepoint( $savepointId, $fname );
3736 $sectionId = new AtomicSectionIdentifier
;
3737 $this->trxAtomicLevels
[] = [ $fname, $sectionId, $savepointId ];
3738 $this->queryLogger
->debug( 'startAtomic: entering level ' .
3739 ( count( $this->trxAtomicLevels
) - 1 ) . " ($fname)" );
3744 final public function endAtomic( $fname = __METHOD__
) {
3745 if ( !$this->trxLevel ||
!$this->trxAtomicLevels
) {
3746 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)." );
3749 // Check if the current section matches $fname
3750 $pos = count( $this->trxAtomicLevels
) - 1;
3751 list( $savedFname, $sectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3752 $this->queryLogger
->debug( "endAtomic: leaving level $pos ($fname)" );
3754 if ( $savedFname !== $fname ) {
3755 throw new DBUnexpectedError(
3757 "Invalid atomic section ended (got $fname but expected $savedFname)."
3761 // Remove the last section (no need to re-index the array)
3762 array_pop( $this->trxAtomicLevels
);
3764 if ( !$this->trxAtomicLevels
&& $this->trxAutomaticAtomic
) {
3765 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3766 } elseif ( $savepointId !== null && $savepointId !== self
::$NOT_APPLICABLE ) {
3767 $this->doReleaseSavepoint( $savepointId, $fname );
3770 // Hoist callback ownership for callbacks in the section that just ended;
3771 // all callbacks should have an owner that is present in trxAtomicLevels.
3772 $currentSectionId = $this->currentAtomicSectionId();
3773 if ( $currentSectionId ) {
3774 $this->reassignCallbacksForSection( $sectionId, $currentSectionId );
3778 final public function cancelAtomic(
3779 $fname = __METHOD__
, AtomicSectionIdentifier
$sectionId = null
3781 if ( !$this->trxLevel ||
!$this->trxAtomicLevels
) {
3782 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)." );
3785 $excisedFnames = [];
3786 if ( $sectionId !== null ) {
3787 // Find the (last) section with the given $sectionId
3789 foreach ( $this->trxAtomicLevels
as $i => list( $asFname, $asId, $spId ) ) {
3790 if ( $asId === $sectionId ) {
3795 throw new DBUnexpectedError( $this, "Atomic section not found (for $fname)" );
3797 // Remove all descendant sections and re-index the array
3799 $len = count( $this->trxAtomicLevels
);
3800 for ( $i = $pos +
1; $i < $len; ++
$i ) {
3801 $excisedFnames[] = $this->trxAtomicLevels
[$i][0];
3802 $excisedIds[] = $this->trxAtomicLevels
[$i][1];
3804 $this->trxAtomicLevels
= array_slice( $this->trxAtomicLevels
, 0, $pos +
1 );
3805 $this->modifyCallbacksForCancel( $excisedIds );
3808 // Check if the current section matches $fname
3809 $pos = count( $this->trxAtomicLevels
) - 1;
3810 list( $savedFname, $savedSectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3812 if ( $excisedFnames ) {
3813 $this->queryLogger
->debug( "cancelAtomic: canceling level $pos ($savedFname) " .
3814 "and descendants " . implode( ', ', $excisedFnames ) );
3816 $this->queryLogger
->debug( "cancelAtomic: canceling level $pos ($savedFname)" );
3819 if ( $savedFname !== $fname ) {
3820 throw new DBUnexpectedError(
3822 "Invalid atomic section ended (got $fname but expected $savedFname)."
3826 // Remove the last section (no need to re-index the array)
3827 array_pop( $this->trxAtomicLevels
);
3828 $this->modifyCallbacksForCancel( [ $savedSectionId ] );
3830 if ( $savepointId !== null ) {
3831 // Rollback the transaction to the state just before this atomic section
3832 if ( $savepointId === self
::$NOT_APPLICABLE ) {
3833 $this->rollback( $fname, self
::FLUSHING_INTERNAL
);
3835 $this->doRollbackToSavepoint( $savepointId, $fname );
3836 $this->trxStatus
= self
::STATUS_TRX_OK
; // no exception; recovered
3837 $this->trxStatusIgnoredCause
= null;
3839 } elseif ( $this->trxStatus
> self
::STATUS_TRX_ERROR
) {
3840 // Put the transaction into an error state if it's not already in one
3841 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
3842 $this->trxStatusCause
= new DBUnexpectedError(
3844 "Uncancelable atomic section canceled (got $fname)."
3848 $this->affectedRowCount
= 0; // for the sake of consistency
3851 final public function doAtomicSection(
3852 $fname, callable
$callback, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3854 $sectionId = $this->startAtomic( $fname, $cancelable );
3856 $res = $callback( $this, $fname );
3857 } catch ( Exception
$e ) {
3858 $this->cancelAtomic( $fname, $sectionId );
3862 $this->endAtomic( $fname );
3867 final public function begin( $fname = __METHOD__
, $mode = self
::TRANSACTION_EXPLICIT
) {
3868 static $modes = [ self
::TRANSACTION_EXPLICIT
, self
::TRANSACTION_INTERNAL
];
3869 if ( !in_array( $mode, $modes, true ) ) {
3870 throw new DBUnexpectedError( $this, "$fname: invalid mode parameter '$mode'." );
3873 // Protect against mismatched atomic section, transaction nesting, and snapshot loss
3874 if ( $this->trxLevel
) {
3875 if ( $this->trxAtomicLevels
) {
3876 $levels = $this->flatAtomicSectionList();
3877 $msg = "$fname: Got explicit BEGIN while atomic section(s) $levels are open.";
3878 throw new DBUnexpectedError( $this, $msg );
3879 } elseif ( !$this->trxAutomatic
) {
3880 $msg = "$fname: Explicit transaction already active (from {$this->trxFname}).";
3881 throw new DBUnexpectedError( $this, $msg );
3883 $msg = "$fname: Implicit transaction already active (from {$this->trxFname}).";
3884 throw new DBUnexpectedError( $this, $msg );
3886 } elseif ( $this->getFlag( self
::DBO_TRX
) && $mode !== self
::TRANSACTION_INTERNAL
) {
3887 $msg = "$fname: Implicit transaction expected (DBO_TRX set).";
3888 throw new DBUnexpectedError( $this, $msg );
3891 $this->assertHasConnectionHandle();
3893 $this->doBegin( $fname );
3894 $this->trxStatus
= self
::STATUS_TRX_OK
;
3895 $this->trxStatusIgnoredCause
= null;
3896 $this->trxAtomicCounter
= 0;
3897 $this->trxTimestamp
= microtime( true );
3898 $this->trxFname
= $fname;
3899 $this->trxDoneWrites
= false;
3900 $this->trxAutomaticAtomic
= false;
3901 $this->trxAtomicLevels
= [];
3902 $this->trxShortId
= sprintf( '%06x', mt_rand( 0, 0xffffff ) );
3903 $this->trxWriteDuration
= 0.0;
3904 $this->trxWriteQueryCount
= 0;
3905 $this->trxWriteAffectedRows
= 0;
3906 $this->trxWriteAdjDuration
= 0.0;
3907 $this->trxWriteAdjQueryCount
= 0;
3908 $this->trxWriteCallers
= [];
3909 // First SELECT after BEGIN will establish the snapshot in REPEATABLE-READ.
3910 // Get an estimate of the replication lag before any such queries.
3911 $this->trxReplicaLag
= null; // clear cached value first
3912 $this->trxReplicaLag
= $this->getApproximateLagStatus()['lag'];
3913 // T147697: make explicitTrxActive() return true until begin() finishes. This way, no
3914 // caller will think its OK to muck around with the transaction just because startAtomic()
3915 // has not yet completed (e.g. setting trxAtomicLevels).
3916 $this->trxAutomatic
= ( $mode === self
::TRANSACTION_INTERNAL
);
3920 * Issues the BEGIN command to the database server.
3922 * @see Database::begin()
3923 * @param string $fname
3925 protected function doBegin( $fname ) {
3926 $this->query( 'BEGIN', $fname );
3927 $this->trxLevel
= 1;
3930 final public function commit( $fname = __METHOD__
, $flush = self
::FLUSHING_ONE
) {
3931 static $modes = [ self
::FLUSHING_ONE
, self
::FLUSHING_ALL_PEERS
, self
::FLUSHING_INTERNAL
];
3932 if ( !in_array( $flush, $modes, true ) ) {
3933 throw new DBUnexpectedError( $this, "$fname: invalid flush parameter '$flush'." );
3936 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3937 // There are still atomic sections open; this cannot be ignored
3938 $levels = $this->flatAtomicSectionList();
3939 throw new DBUnexpectedError(
3941 "$fname: Got COMMIT while atomic sections $levels are still open."
3945 if ( $flush === self
::FLUSHING_INTERNAL ||
$flush === self
::FLUSHING_ALL_PEERS
) {
3946 if ( !$this->trxLevel
) {
3947 return; // nothing to do
3948 } elseif ( !$this->trxAutomatic
) {
3949 throw new DBUnexpectedError(
3951 "$fname: Flushing an explicit transaction, getting out of sync."
3955 if ( !$this->trxLevel
) {
3956 $this->queryLogger
->error(
3957 "$fname: No transaction to commit, something got out of sync." );
3958 return; // nothing to do
3959 } elseif ( $this->trxAutomatic
) {
3960 throw new DBUnexpectedError(
3962 "$fname: Expected mass commit of all peer transactions (DBO_TRX set)."
3967 $this->assertHasConnectionHandle();
3969 $this->runOnTransactionPreCommitCallbacks();
3971 $writeTime = $this->pendingWriteQueryDuration( self
::ESTIMATE_DB_APPLY
);
3972 $this->doCommit( $fname );
3973 $this->trxStatus
= self
::STATUS_TRX_NONE
;
3975 if ( $this->trxDoneWrites
) {
3976 $this->lastWriteTime
= microtime( true );
3977 $this->trxProfiler
->transactionWritingOut(
3979 $this->getDomainID(),
3982 $this->trxWriteAffectedRows
3986 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
3987 if ( $flush !== self
::FLUSHING_ALL_PEERS
) {
3988 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_COMMIT
);
3989 $this->runTransactionListenerCallbacks( self
::TRIGGER_COMMIT
);
3994 * Issues the COMMIT command to the database server.
3996 * @see Database::commit()
3997 * @param string $fname
3999 protected function doCommit( $fname ) {
4000 if ( $this->trxLevel
) {
4001 $this->query( 'COMMIT', $fname );
4002 $this->trxLevel
= 0;
4006 final public function rollback( $fname = __METHOD__
, $flush = '' ) {
4007 $trxActive = $this->trxLevel
;
4009 if ( $flush !== self
::FLUSHING_INTERNAL
&& $flush !== self
::FLUSHING_ALL_PEERS
) {
4010 if ( $this->getFlag( self
::DBO_TRX
) ) {
4011 throw new DBUnexpectedError(
4013 "$fname: Expected mass rollback of all peer transactions (DBO_TRX set)."
4019 $this->assertHasConnectionHandle();
4021 $this->doRollback( $fname );
4022 $this->trxStatus
= self
::STATUS_TRX_NONE
;
4023 $this->trxAtomicLevels
= [];
4024 // Estimate the RTT via a query now that trxStatus is OK
4025 $writeTime = $this->pingAndCalculateLastTrxApplyTime();
4027 if ( $this->trxDoneWrites
) {
4028 $this->trxProfiler
->transactionWritingOut(
4030 $this->getDomainID(),
4033 $this->trxWriteAffectedRows
4038 // Clear any commit-dependant callbacks. They might even be present
4039 // only due to transaction rounds, with no SQL transaction being active
4040 $this->trxIdleCallbacks
= [];
4041 $this->trxPreCommitCallbacks
= [];
4043 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
4044 if ( $trxActive && $flush !== self
::FLUSHING_ALL_PEERS
) {
4046 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
4047 } catch ( Exception
$e ) {
4048 // already logged; finish and let LoadBalancer move on during mass-rollback
4051 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
4052 } catch ( Exception
$e ) {
4053 // already logged; let LoadBalancer move on during mass-rollback
4056 $this->affectedRowCount
= 0; // for the sake of consistency
4061 * Issues the ROLLBACK command to the database server.
4063 * @see Database::rollback()
4064 * @param string $fname
4066 protected function doRollback( $fname ) {
4067 if ( $this->trxLevel
) {
4068 # Disconnects cause rollback anyway, so ignore those errors
4069 $ignoreErrors = true;
4070 $this->query( 'ROLLBACK', $fname, $ignoreErrors );
4071 $this->trxLevel
= 0;
4075 public function flushSnapshot( $fname = __METHOD__
) {
4076 if ( $this->writesOrCallbacksPending() ||
$this->explicitTrxActive() ) {
4077 // This only flushes transactions to clear snapshots, not to write data
4078 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4079 throw new DBUnexpectedError(
4081 "$fname: Cannot flush snapshot because writes are pending ($fnames)."
4085 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4088 public function explicitTrxActive() {
4089 return $this->trxLevel
&& ( $this->trxAtomicLevels ||
!$this->trxAutomatic
);
4092 public function duplicateTableStructure(
4093 $oldName, $newName, $temporary = false, $fname = __METHOD__
4095 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4098 public function listTables( $prefix = null, $fname = __METHOD__
) {
4099 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4102 public function listViews( $prefix = null, $fname = __METHOD__
) {
4103 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4106 public function timestamp( $ts = 0 ) {
4107 $t = new ConvertibleTimestamp( $ts );
4108 // Let errors bubble up to avoid putting garbage in the DB
4109 return $t->getTimestamp( TS_MW
);
4112 public function timestampOrNull( $ts = null ) {
4113 if ( is_null( $ts ) ) {
4116 return $this->timestamp( $ts );
4120 public function affectedRows() {
4121 return ( $this->affectedRowCount
=== null )
4122 ?
$this->fetchAffectedRowCount() // default to driver value
4123 : $this->affectedRowCount
;
4127 * @return int Number of retrieved rows according to the driver
4129 abstract protected function fetchAffectedRowCount();
4132 * Take the result from a query, and wrap it in a ResultWrapper if
4133 * necessary. Boolean values are passed through as is, to indicate success
4134 * of write queries or failure.
4136 * Once upon a time, Database::query() returned a bare MySQL result
4137 * resource, and it was necessary to call this function to convert it to
4138 * a wrapper. Nowadays, raw database objects are never exposed to external
4139 * callers, so this is unnecessary in external code.
4141 * @param bool|ResultWrapper|resource $result
4142 * @return bool|ResultWrapper
4144 protected function resultObject( $result ) {
4147 } elseif ( $result instanceof ResultWrapper
) {
4149 } elseif ( $result === true ) {
4150 // Successful write query
4153 return new ResultWrapper( $this, $result );
4157 public function ping( &$rtt = null ) {
4158 // Avoid hitting the server if it was hit recently
4159 if ( $this->isOpen() && ( microtime( true ) - $this->lastPing
) < self
::PING_TTL
) {
4160 if ( !func_num_args() ||
$this->rttEstimate
> 0 ) {
4161 $rtt = $this->rttEstimate
;
4162 return true; // don't care about $rtt
4166 // This will reconnect if possible or return false if not
4167 $this->clearFlag( self
::DBO_TRX
, self
::REMEMBER_PRIOR
);
4168 $ok = ( $this->query( self
::PING_QUERY
, __METHOD__
, true ) !== false );
4169 $this->restoreFlags( self
::RESTORE_PRIOR
);
4172 $rtt = $this->rttEstimate
;
4179 * Close any existing (dead) database connection and open a new connection
4181 * @param string $fname
4182 * @return bool True if new connection is opened successfully, false if error
4184 protected function replaceLostConnection( $fname ) {
4185 $this->closeConnection();
4186 $this->opened
= false;
4187 $this->conn
= false;
4189 $this->handleSessionLossPreconnect();
4198 $this->tablePrefix()
4200 $this->lastPing
= microtime( true );
4203 $this->connLogger
->warning(
4204 $fname . ': lost connection to {dbserver}; reconnected',
4206 'dbserver' => $this->getServer(),
4207 'trace' => ( new RuntimeException() )->getTraceAsString()
4210 } catch ( DBConnectionError
$e ) {
4213 $this->connLogger
->error(
4214 $fname . ': lost connection to {dbserver} permanently',
4215 [ 'dbserver' => $this->getServer() ]
4219 $this->handleSessionLossPostconnect();
4224 public function getSessionLagStatus() {
4225 return $this->getRecordedTransactionLagStatus() ?
: $this->getApproximateLagStatus();
4229 * Get the replica DB lag when the current transaction started
4231 * This is useful when transactions might use snapshot isolation
4232 * (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data
4233 * is this lag plus transaction duration. If they don't, it is still
4234 * safe to be pessimistic. This returns null if there is no transaction.
4236 * This returns null if the lag status for this transaction was not yet recorded.
4238 * @return array|null ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)
4241 final protected function getRecordedTransactionLagStatus() {
4242 return ( $this->trxLevel
&& $this->trxReplicaLag
!== null )
4243 ?
[ 'lag' => $this->trxReplicaLag
, 'since' => $this->trxTimestamp() ]
4248 * Get a replica DB lag estimate for this server
4250 * @return array ('lag': seconds or false on error, 'since': UNIX timestamp of estimate)
4253 protected function getApproximateLagStatus() {
4255 'lag' => $this->getLBInfo( 'replica' ) ?
$this->getLag() : 0,
4256 'since' => microtime( true )
4261 * Merge the result of getSessionLagStatus() for several DBs
4262 * using the most pessimistic values to estimate the lag of
4263 * any data derived from them in combination
4265 * This is information is useful for caching modules
4267 * @see WANObjectCache::set()
4268 * @see WANObjectCache::getWithSetCallback()
4270 * @param IDatabase $db1
4271 * @param IDatabase|null $db2 [optional]
4272 * @return array Map of values:
4273 * - lag: highest lag of any of the DBs or false on error (e.g. replication stopped)
4274 * - since: oldest UNIX timestamp of any of the DB lag estimates
4275 * - pending: whether any of the DBs have uncommitted changes
4279 public static function getCacheSetOptions( IDatabase
$db1, IDatabase
$db2 = null ) {
4280 $res = [ 'lag' => 0, 'since' => INF
, 'pending' => false ];
4281 foreach ( func_get_args() as $db ) {
4282 /** @var IDatabase $db */
4283 $status = $db->getSessionLagStatus();
4284 if ( $status['lag'] === false ) {
4285 $res['lag'] = false;
4286 } elseif ( $res['lag'] !== false ) {
4287 $res['lag'] = max( $res['lag'], $status['lag'] );
4289 $res['since'] = min( $res['since'], $status['since'] );
4290 $res['pending'] = $res['pending'] ?
: $db->writesPending();
4296 public function getLag() {
4300 public function maxListLen() {
4304 public function encodeBlob( $b ) {
4308 public function decodeBlob( $b ) {
4309 if ( $b instanceof Blob
) {
4315 public function setSessionOptions( array $options ) {
4318 public function sourceFile(
4320 callable
$lineCallback = null,
4321 callable
$resultCallback = null,
4323 callable
$inputCallback = null
4325 Wikimedia\
suppressWarnings();
4326 $fp = fopen( $filename, 'r' );
4327 Wikimedia\restoreWarnings
();
4329 if ( $fp === false ) {
4330 throw new RuntimeException( "Could not open \"{$filename}\".\n" );
4334 $fname = __METHOD__
. "( $filename )";
4338 $error = $this->sourceStream(
4339 $fp, $lineCallback, $resultCallback, $fname, $inputCallback );
4340 } catch ( Exception
$e ) {
4350 public function setSchemaVars( $vars ) {
4351 $this->schemaVars
= $vars;
4354 public function sourceStream(
4356 callable
$lineCallback = null,
4357 callable
$resultCallback = null,
4358 $fname = __METHOD__
,
4359 callable
$inputCallback = null
4361 $delimiterReset = new ScopedCallback(
4362 function ( $delimiter ) {
4363 $this->delimiter
= $delimiter;
4365 [ $this->delimiter
]
4369 while ( !feof( $fp ) ) {
4370 if ( $lineCallback ) {
4371 call_user_func( $lineCallback );
4374 $line = trim( fgets( $fp ) );
4376 if ( $line == '' ) {
4380 if ( $line[0] == '-' && $line[1] == '-' ) {
4388 $done = $this->streamStatementEnd( $cmd, $line );
4392 if ( $done ||
feof( $fp ) ) {
4393 $cmd = $this->replaceVars( $cmd );
4395 if ( $inputCallback ) {
4396 $callbackResult = $inputCallback( $cmd );
4398 if ( is_string( $callbackResult ) ||
!$callbackResult ) {
4399 $cmd = $callbackResult;
4404 $res = $this->query( $cmd, $fname );
4406 if ( $resultCallback ) {
4407 $resultCallback( $res, $this );
4410 if ( $res === false ) {
4411 $err = $this->lastError();
4413 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
4420 ScopedCallback
::consume( $delimiterReset );
4425 * Called by sourceStream() to check if we've reached a statement end
4427 * @param string &$sql SQL assembled so far
4428 * @param string &$newLine New line about to be added to $sql
4429 * @return bool Whether $newLine contains end of the statement
4431 public function streamStatementEnd( &$sql, &$newLine ) {
4432 if ( $this->delimiter
) {
4434 $newLine = preg_replace(
4435 '/' . preg_quote( $this->delimiter
, '/' ) . '$/', '', $newLine );
4436 if ( $newLine != $prev ) {
4445 * Database independent variable replacement. Replaces a set of variables
4446 * in an SQL statement with their contents as given by $this->getSchemaVars().
4448 * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables.
4450 * - '{$var}' should be used for text and is passed through the database's
4452 * - `{$var}` should be used for identifiers (e.g. table and database names).
4453 * It is passed through the database's addIdentifierQuotes method which
4454 * can be overridden if the database uses something other than backticks.
4455 * - / *_* / or / *$wgDBprefix* / passes the name that follows through the
4456 * database's tableName method.
4457 * - / *i* / passes the name that follows through the database's indexName method.
4458 * - In all other cases, / *$var* / is left unencoded. Except for table options,
4459 * its use should be avoided. In 1.24 and older, string encoding was applied.
4461 * @param string $ins SQL statement to replace variables in
4462 * @return string The new SQL statement with variables replaced
4464 protected function replaceVars( $ins ) {
4465 $vars = $this->getSchemaVars();
4466 return preg_replace_callback(
4468 /\* (\$wgDBprefix|[_i]) \*/ (\w*) | # 1-2. tableName, indexName
4469 \'\{\$ (\w+) }\' | # 3. addQuotes
4470 `\{\$ (\w+) }` | # 4. addIdentifierQuotes
4471 /\*\$ (\w+) \*/ # 5. leave unencoded
4473 function ( $m ) use ( $vars ) {
4474 // Note: Because of <https://bugs.php.net/bug.php?id=51881>,
4475 // check for both nonexistent keys *and* the empty string.
4476 if ( isset( $m[1] ) && $m[1] !== '' ) {
4477 if ( $m[1] === 'i' ) {
4478 return $this->indexName( $m[2] );
4480 return $this->tableName( $m[2] );
4482 } elseif ( isset( $m[3] ) && $m[3] !== '' && array_key_exists( $m[3], $vars ) ) {
4483 return $this->addQuotes( $vars[$m[3]] );
4484 } elseif ( isset( $m[4] ) && $m[4] !== '' && array_key_exists( $m[4], $vars ) ) {
4485 return $this->addIdentifierQuotes( $vars[$m[4]] );
4486 } elseif ( isset( $m[5] ) && $m[5] !== '' && array_key_exists( $m[5], $vars ) ) {
4487 return $vars[$m[5]];
4497 * Get schema variables. If none have been set via setSchemaVars(), then
4498 * use some defaults from the current object.
4502 protected function getSchemaVars() {
4503 if ( $this->schemaVars
) {
4504 return $this->schemaVars
;
4506 return $this->getDefaultSchemaVars();
4511 * Get schema variables to use if none have been set via setSchemaVars().
4513 * Override this in derived classes to provide variables for tables.sql
4514 * and SQL patch files.
4518 protected function getDefaultSchemaVars() {
4522 public function lockIsFree( $lockName, $method ) {
4523 // RDBMs methods for checking named locks may or may not count this thread itself.
4524 // In MySQL, IS_FREE_LOCK() returns 0 if the thread already has the lock. This is
4525 // the behavior choosen by the interface for this method.
4526 return !isset( $this->namedLocksHeld
[$lockName] );
4529 public function lock( $lockName, $method, $timeout = 5 ) {
4530 $this->namedLocksHeld
[$lockName] = 1;
4535 public function unlock( $lockName, $method ) {
4536 unset( $this->namedLocksHeld
[$lockName] );
4541 public function getScopedLockAndFlush( $lockKey, $fname, $timeout ) {
4542 if ( $this->writesOrCallbacksPending() ) {
4543 // This only flushes transactions to clear snapshots, not to write data
4544 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4545 throw new DBUnexpectedError(
4547 "$fname: Cannot flush pre-lock snapshot because writes are pending ($fnames)."
4551 if ( !$this->lock( $lockKey, $fname, $timeout ) ) {
4555 $unlocker = new ScopedCallback( function () use ( $lockKey, $fname ) {
4556 if ( $this->trxLevel() ) {
4557 // There is a good chance an exception was thrown, causing any early return
4558 // from the caller. Let any error handler get a chance to issue rollback().
4559 // If there isn't one, let the error bubble up and trigger server-side rollback.
4560 $this->onTransactionResolution(
4561 function () use ( $lockKey, $fname ) {
4562 $this->unlock( $lockKey, $fname );
4567 $this->unlock( $lockKey, $fname );
4571 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4576 public function namedLocksEnqueue() {
4580 public function tableLocksHaveTransactionScope() {
4584 final public function lockTables( array $read, array $write, $method ) {
4585 if ( $this->writesOrCallbacksPending() ) {
4586 throw new DBUnexpectedError( $this, "Transaction writes or callbacks still pending." );
4589 if ( $this->tableLocksHaveTransactionScope() ) {
4590 $this->startAtomic( $method );
4593 return $this->doLockTables( $read, $write, $method );
4597 * Helper function for lockTables() that handles the actual table locking
4599 * @param array $read Array of tables to lock for read access
4600 * @param array $write Array of tables to lock for write access
4601 * @param string $method Name of caller
4604 protected function doLockTables( array $read, array $write, $method ) {
4608 final public function unlockTables( $method ) {
4609 if ( $this->tableLocksHaveTransactionScope() ) {
4610 $this->endAtomic( $method );
4612 return true; // locks released on COMMIT/ROLLBACK
4615 return $this->doUnlockTables( $method );
4619 * Helper function for unlockTables() that handles the actual table unlocking
4621 * @param string $method Name of caller
4624 protected function doUnlockTables( $method ) {
4630 * @param string $tableName
4631 * @param string $fName
4632 * @return bool|ResultWrapper
4635 public function dropTable( $tableName, $fName = __METHOD__
) {
4636 if ( !$this->tableExists( $tableName, $fName ) ) {
4639 $sql = "DROP TABLE " . $this->tableName( $tableName ) . " CASCADE";
4641 return $this->query( $sql, $fName );
4644 public function getInfinity() {
4648 public function encodeExpiry( $expiry ) {
4649 return ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() )
4650 ?
$this->getInfinity()
4651 : $this->timestamp( $expiry );
4654 public function decodeExpiry( $expiry, $format = TS_MW
) {
4655 if ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() ) {
4659 return ConvertibleTimestamp
::convert( $format, $expiry );
4662 public function setBigSelects( $value = true ) {
4666 public function isReadOnly() {
4667 return ( $this->getReadOnlyReason() !== false );
4671 * @return string|bool Reason this DB is read-only or false if it is not
4673 protected function getReadOnlyReason() {
4674 $reason = $this->getLBInfo( 'readOnlyReason' );
4676 return is_string( $reason ) ?
$reason : false;
4679 public function setTableAliases( array $aliases ) {
4680 $this->tableAliases
= $aliases;
4683 public function setIndexAliases( array $aliases ) {
4684 $this->indexAliases
= $aliases;
4688 * Get the underlying binding connection handle
4690 * Makes sure the connection resource is set (disconnects and ping() failure can unset it).
4691 * This catches broken callers than catch and ignore disconnection exceptions.
4692 * Unlike checking isOpen(), this is safe to call inside of open().
4695 * @throws DBUnexpectedError
4698 protected function getBindingHandle() {
4699 if ( !$this->conn
) {
4700 throw new DBUnexpectedError(
4702 'DB connection was already closed or the connection dropped.'
4713 public function __toString() {
4714 return (string)$this->conn
;
4718 * Make sure that copies do not share the same client binding handle
4719 * @throws DBConnectionError
4721 public function __clone() {
4722 $this->connLogger
->warning(
4723 "Cloning " . static::class . " is not recommended; forking connection:\n" .
4724 ( new RuntimeException() )->getTraceAsString()
4727 if ( $this->isOpen() ) {
4728 // Open a new connection resource without messing with the old one
4729 $this->opened
= false;
4730 $this->conn
= false;
4731 $this->trxEndCallbacks
= []; // don't copy
4732 $this->handleSessionLossPreconnect(); // no trx or locks anymore
4739 $this->tablePrefix()
4741 $this->lastPing
= microtime( true );
4746 * Called by serialize. Throw an exception when DB connection is serialized.
4747 * This causes problems on some database engines because the connection is
4748 * not restored on unserialize.
4750 public function __sleep() {
4751 throw new RuntimeException( 'Database serialization may cause problems, since ' .
4752 'the connection is not restored on wakeup.' );
4756 * Run a few simple sanity checks and close dangling connections
4758 public function __destruct() {
4759 if ( $this->trxLevel
&& $this->trxDoneWrites
) {
4760 trigger_error( "Uncommitted DB writes (transaction from {$this->trxFname})." );
4763 $danglingWriters = $this->pendingWriteAndCallbackCallers();
4764 if ( $danglingWriters ) {
4765 $fnames = implode( ', ', $danglingWriters );
4766 trigger_error( "DB transaction writes or callbacks still pending ($fnames)." );
4769 if ( $this->conn
) {
4770 // Avoid connection leaks for sanity. Normally, resources close at script completion.
4771 // The connection might already be closed in zend/hhvm by now, so suppress warnings.
4772 Wikimedia\
suppressWarnings();
4773 $this->closeConnection();
4774 Wikimedia\restoreWarnings
();
4775 $this->conn
= false;
4776 $this->opened
= false;
4782 * @deprecated since 1.28
4784 class_alias( Database
::class, 'DatabaseBase' );
4787 * @deprecated since 1.29
4789 class_alias( Database
::class, 'Database' );