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;
283 /** @var int Writes to this temporary table do not affect lastDoneWrites() */
284 const TEMP_NORMAL
= 1;
285 /** @var int Writes to this temporary table effect lastDoneWrites() */
286 const TEMP_PSEUDO_PERMANENT
= 2;
289 * @note exceptions for missing libraries/drivers should be thrown in initConnection()
290 * @param array $params Parameters passed from Database::factory()
292 protected function __construct( array $params ) {
293 foreach ( [ 'host', 'user', 'password', 'dbname', 'schema', 'tablePrefix' ] as $name ) {
294 $this->connectionParams
[$name] = $params[$name];
297 $this->cliMode
= $params['cliMode'];
298 // Agent name is added to SQL queries in a comment, so make sure it can't break out
299 $this->agent
= str_replace( '/', '-', $params['agent'] );
301 $this->flags
= $params['flags'];
302 if ( $this->flags
& self
::DBO_DEFAULT
) {
303 if ( $this->cliMode
) {
304 $this->flags
&= ~self
::DBO_TRX
;
306 $this->flags |
= self
::DBO_TRX
;
309 // Disregard deprecated DBO_IGNORE flag (T189999)
310 $this->flags
&= ~self
::DBO_IGNORE
;
312 $this->sessionVars
= $params['variables'];
314 $this->srvCache
= $params['srvCache'] ??
new HashBagOStuff();
316 $this->profiler
= is_callable( $params['profiler'] ) ?
$params['profiler'] : null;
317 $this->trxProfiler
= $params['trxProfiler'];
318 $this->connLogger
= $params['connLogger'];
319 $this->queryLogger
= $params['queryLogger'];
320 $this->errorLogger
= $params['errorLogger'];
321 $this->deprecationLogger
= $params['deprecationLogger'];
323 if ( isset( $params['nonNativeInsertSelectBatchSize'] ) ) {
324 $this->nonNativeInsertSelectBatchSize
= $params['nonNativeInsertSelectBatchSize'];
327 // Set initial dummy domain until open() sets the final DB/prefix
328 $this->currentDomain
= new DatabaseDomain(
329 $params['dbname'] != '' ?
$params['dbname'] : null,
330 $params['schema'] != '' ?
$params['schema'] : null,
331 $params['tablePrefix']
336 * Initialize the connection to the database over the wire (or to local files)
338 * @throws LogicException
339 * @throws InvalidArgumentException
340 * @throws DBConnectionError
343 final public function initConnection() {
344 if ( $this->isOpen() ) {
345 throw new LogicException( __METHOD__
. ': already connected.' );
347 // Establish the connection
348 $this->doInitConnection();
352 * Actually connect to the database over the wire (or to local files)
354 * @throws InvalidArgumentException
355 * @throws DBConnectionError
358 protected function doInitConnection() {
359 if ( strlen( $this->connectionParams
['user'] ) ) {
361 $this->connectionParams
['host'],
362 $this->connectionParams
['user'],
363 $this->connectionParams
['password'],
364 $this->connectionParams
['dbname'],
365 $this->connectionParams
['schema'],
366 $this->connectionParams
['tablePrefix']
369 throw new InvalidArgumentException( "No database user provided." );
374 * Open a new connection to the database (closing any existing one)
376 * @param string $server Database server host
377 * @param string $user Database user name
378 * @param string $password Database user password
379 * @param string $dbName Database name
380 * @param string|null $schema Database schema name
381 * @param string $tablePrefix Table prefix
383 * @throws DBConnectionError
385 abstract protected function open( $server, $user, $password, $dbName, $schema, $tablePrefix );
388 * Construct a Database subclass instance given a database type and parameters
390 * This also connects to the database immediately upon object construction
392 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
393 * @param array $p Parameter map with keys:
394 * - host : The hostname of the DB server
395 * - user : The name of the database user the client operates under
396 * - password : The password for the database user
397 * - dbname : The name of the database to use where queries do not specify one.
398 * The database must exist or an error might be thrown. Setting this to the empty string
399 * will avoid any such errors and make the handle have no implicit database scope. This is
400 * useful for queries like SHOW STATUS, CREATE DATABASE, or DROP DATABASE. Note that a
401 * "database" in Postgres is rougly equivalent to an entire MySQL server. This the domain
402 * in which user names and such are defined, e.g. users are database-specific in Postgres.
403 * - schema : The database schema to use (if supported). A "schema" in Postgres is roughly
404 * equivalent to a "database" in MySQL. Note that MySQL and SQLite do not use schemas.
405 * - tablePrefix : Optional table prefix that is implicitly added on to all table names
406 * recognized in queries. This can be used in place of schemas for handle site farms.
407 * - flags : Optional bitfield of DBO_* constants that define connection, protocol,
408 * buffering, and transaction behavior. It is STRONGLY adviced to leave the DBO_DEFAULT
409 * flag in place UNLESS this this database simply acts as a key/value store.
410 * - driver: Optional name of a specific DB client driver. For MySQL, there is only the
411 * 'mysqli' driver; the old one 'mysql' has been removed.
412 * - variables: Optional map of session variables to set after connecting. This can be
413 * used to adjust lock timeouts or encoding modes and the like.
414 * - connLogger: Optional PSR-3 logger interface instance.
415 * - queryLogger: Optional PSR-3 logger interface instance.
416 * - profiler : Optional callback that takes a section name argument and returns
417 * a ScopedCallback instance that ends the profile section in its destructor.
418 * These will be called in query(), using a simplified version of the SQL that
419 * also includes the agent as a SQL comment.
420 * - trxProfiler: Optional TransactionProfiler instance.
421 * - errorLogger: Optional callback that takes an Exception and logs it.
422 * - deprecationLogger: Optional callback that takes a string and logs it.
423 * - cliMode: Whether to consider the execution context that of a CLI script.
424 * - agent: Optional name used to identify the end-user in query profiling/logging.
425 * - srvCache: Optional BagOStuff instance to an APC-style cache.
426 * - nonNativeInsertSelectBatchSize: Optional batch size for non-native INSERT SELECT emulation.
427 * @param int $connect One of the class constants (NEW_CONNECTED, NEW_UNCONNECTED) [optional]
428 * @return Database|null If the database driver or extension cannot be found
429 * @throws InvalidArgumentException If the database driver or extension cannot be found
432 final public static function factory( $dbType, $p = [], $connect = self
::NEW_CONNECTED
) {
433 $class = self
::getClass( $dbType, $p['driver'] ??
null );
435 if ( class_exists( $class ) && is_subclass_of( $class, IDatabase
::class ) ) {
436 // Resolve some defaults for b/c
437 $p['host'] = $p['host'] ??
false;
438 $p['user'] = $p['user'] ??
false;
439 $p['password'] = $p['password'] ??
false;
440 $p['dbname'] = $p['dbname'] ??
false;
441 $p['flags'] = $p['flags'] ??
0;
442 $p['variables'] = $p['variables'] ??
[];
443 $p['tablePrefix'] = $p['tablePrefix'] ??
'';
444 $p['schema'] = $p['schema'] ??
null;
445 $p['cliMode'] = $p['cliMode'] ??
( PHP_SAPI
=== 'cli' || PHP_SAPI
=== 'phpdbg' );
446 $p['agent'] = $p['agent'] ??
'';
447 if ( !isset( $p['connLogger'] ) ) {
448 $p['connLogger'] = new NullLogger();
450 if ( !isset( $p['queryLogger'] ) ) {
451 $p['queryLogger'] = new NullLogger();
453 $p['profiler'] = $p['profiler'] ??
null;
454 if ( !isset( $p['trxProfiler'] ) ) {
455 $p['trxProfiler'] = new TransactionProfiler();
457 if ( !isset( $p['errorLogger'] ) ) {
458 $p['errorLogger'] = function ( Exception
$e ) {
459 trigger_error( get_class( $e ) . ': ' . $e->getMessage(), E_USER_WARNING
);
462 if ( !isset( $p['deprecationLogger'] ) ) {
463 $p['deprecationLogger'] = function ( $msg ) {
464 trigger_error( $msg, E_USER_DEPRECATED
);
468 /** @var Database $conn */
469 $conn = new $class( $p );
470 if ( $connect == self
::NEW_CONNECTED
) {
471 $conn->initConnection();
481 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
482 * @param string|null $driver Optional name of a specific DB client driver
483 * @return array Map of (Database::ATTRIBUTE_* constant => value) for all such constants
484 * @throws InvalidArgumentException
487 final public static function attributesFromType( $dbType, $driver = null ) {
488 static $defaults = [ self
::ATTR_DB_LEVEL_LOCKING
=> false ];
490 $class = self
::getClass( $dbType, $driver );
492 return call_user_func( [ $class, 'getAttributes' ] ) +
$defaults;
496 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
497 * @param string|null $driver Optional name of a specific DB client driver
498 * @return string Database subclass name to use
499 * @throws InvalidArgumentException
501 private static function getClass( $dbType, $driver = null ) {
502 // For database types with built-in support, the below maps type to IDatabase
503 // implementations. For types with multipe driver implementations (PHP extensions),
504 // an array can be used, keyed by extension name. In case of an array, the
505 // optional 'driver' parameter can be used to force a specific driver. Otherwise,
506 // we auto-detect the first available driver. For types without built-in support,
507 // an class named "Database<Type>" us used, eg. DatabaseFoo for type 'foo'.
508 static $builtinTypes = [
509 'mssql' => DatabaseMssql
::class,
510 'mysql' => [ 'mysqli' => DatabaseMysqli
::class ],
511 'sqlite' => DatabaseSqlite
::class,
512 'postgres' => DatabasePostgres
::class,
515 $dbType = strtolower( $dbType );
518 if ( isset( $builtinTypes[$dbType] ) ) {
519 $possibleDrivers = $builtinTypes[$dbType];
520 if ( is_string( $possibleDrivers ) ) {
521 $class = $possibleDrivers;
523 if ( (string)$driver !== '' ) {
524 if ( !isset( $possibleDrivers[$driver] ) ) {
525 throw new InvalidArgumentException( __METHOD__
.
526 " type '$dbType' does not support driver '{$driver}'" );
528 $class = $possibleDrivers[$driver];
531 foreach ( $possibleDrivers as $posDriver => $possibleClass ) {
532 if ( extension_loaded( $posDriver ) ) {
533 $class = $possibleClass;
540 $class = 'Database' . ucfirst( $dbType );
543 if ( $class === false ) {
544 throw new InvalidArgumentException( __METHOD__
.
545 " no viable database extension found for type '$dbType'" );
552 * @return array Map of (Database::ATTRIBUTE_* constant => value
555 protected static function getAttributes() {
560 * Set the PSR-3 logger interface to use for query logging. (The logger
561 * interfaces for connection logging and error logging can be set with the
564 * @param LoggerInterface $logger
566 public function setLogger( LoggerInterface
$logger ) {
567 $this->queryLogger
= $logger;
570 public function getServerInfo() {
571 return $this->getServerVersion();
574 public function bufferResults( $buffer = null ) {
575 $res = !$this->getFlag( self
::DBO_NOBUFFER
);
576 if ( $buffer !== null ) {
578 ?
$this->clearFlag( self
::DBO_NOBUFFER
)
579 : $this->setFlag( self
::DBO_NOBUFFER
);
585 public function trxLevel() {
586 return $this->trxLevel
;
589 public function trxTimestamp() {
590 return $this->trxLevel ?
$this->trxTimestamp
: null;
594 * @return int One of the STATUS_TRX_* class constants
597 public function trxStatus() {
598 return $this->trxStatus
;
601 public function tablePrefix( $prefix = null ) {
602 $old = $this->currentDomain
->getTablePrefix();
603 if ( $prefix !== null ) {
604 $this->currentDomain
= new DatabaseDomain(
605 $this->currentDomain
->getDatabase(),
606 $this->currentDomain
->getSchema(),
614 public function dbSchema( $schema = null ) {
615 $old = $this->currentDomain
->getSchema();
616 if ( $schema !== null ) {
617 $this->currentDomain
= new DatabaseDomain(
618 $this->currentDomain
->getDatabase(),
619 // DatabaseDomain uses null for unspecified schemas
620 strlen( $schema ) ?
$schema : null,
621 $this->currentDomain
->getTablePrefix()
629 * @return string Schema to use to qualify relations in queries
631 protected function relationSchemaQualifier() {
632 return $this->dbSchema();
635 public function getLBInfo( $name = null ) {
636 if ( is_null( $name ) ) {
637 return $this->lbInfo
;
639 if ( array_key_exists( $name, $this->lbInfo
) ) {
640 return $this->lbInfo
[$name];
647 public function setLBInfo( $name, $value = null ) {
648 if ( is_null( $value ) ) {
649 $this->lbInfo
= $name;
651 $this->lbInfo
[$name] = $value;
655 public function setLazyMasterHandle( IDatabase
$conn ) {
656 $this->lazyMasterHandle
= $conn;
660 * @return IDatabase|null
661 * @see setLazyMasterHandle()
664 protected function getLazyMasterHandle() {
665 return $this->lazyMasterHandle
;
668 public function implicitGroupby() {
672 public function implicitOrderby() {
676 public function lastQuery() {
677 return $this->lastQuery
;
680 public function doneWrites() {
681 return (bool)$this->lastWriteTime
;
684 public function lastDoneWrites() {
685 return $this->lastWriteTime ?
: false;
688 public function writesPending() {
689 return $this->trxLevel
&& $this->trxDoneWrites
;
692 public function writesOrCallbacksPending() {
693 return $this->trxLevel
&& (
694 $this->trxDoneWrites ||
695 $this->trxIdleCallbacks ||
696 $this->trxPreCommitCallbacks ||
697 $this->trxEndCallbacks
701 public function preCommitCallbacksPending() {
702 return $this->trxLevel
&& $this->trxPreCommitCallbacks
;
706 * @return string|null
708 final protected function getTransactionRoundId() {
709 // If transaction round participation is enabled, see if one is active
710 if ( $this->getFlag( self
::DBO_TRX
) ) {
711 $id = $this->getLBInfo( 'trxRoundId' );
713 return is_string( $id ) ?
$id : null;
719 public function pendingWriteQueryDuration( $type = self
::ESTIMATE_TOTAL
) {
720 if ( !$this->trxLevel
) {
722 } elseif ( !$this->trxDoneWrites
) {
727 case self
::ESTIMATE_DB_APPLY
:
728 return $this->pingAndCalculateLastTrxApplyTime();
729 default: // everything
730 return $this->trxWriteDuration
;
735 * @return float Time to apply writes to replicas based on trxWrite* fields
737 private function pingAndCalculateLastTrxApplyTime() {
740 $rttAdjTotal = $this->trxWriteAdjQueryCount
* $rtt;
741 $applyTime = max( $this->trxWriteAdjDuration
- $rttAdjTotal, 0 );
742 // For omitted queries, make them count as something at least
743 $omitted = $this->trxWriteQueryCount
- $this->trxWriteAdjQueryCount
;
744 $applyTime +
= self
::TINY_WRITE_SEC
* $omitted;
749 public function pendingWriteCallers() {
750 return $this->trxLevel ?
$this->trxWriteCallers
: [];
753 public function pendingWriteRowsAffected() {
754 return $this->trxWriteAffectedRows
;
758 * List the methods that have write queries or callbacks for the current transaction
760 * This method should not be used outside of Database/LoadBalancer
765 public function pendingWriteAndCallbackCallers() {
766 $fnames = $this->pendingWriteCallers();
768 $this->trxIdleCallbacks
,
769 $this->trxPreCommitCallbacks
,
770 $this->trxEndCallbacks
772 foreach ( $callbacks as $callback ) {
773 $fnames[] = $callback[1];
783 private function flatAtomicSectionList() {
784 return array_reduce( $this->trxAtomicLevels
, function ( $accum, $v ) {
785 return $accum === null ?
$v[0] : "$accum, " . $v[0];
789 public function isOpen() {
790 return $this->opened
;
793 public function setFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
794 if ( ( $flag & self
::DBO_IGNORE
) ) {
795 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
798 if ( $remember === self
::REMEMBER_PRIOR
) {
799 array_push( $this->priorFlags
, $this->flags
);
801 $this->flags |
= $flag;
804 public function clearFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
805 if ( ( $flag & self
::DBO_IGNORE
) ) {
806 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed." );
809 if ( $remember === self
::REMEMBER_PRIOR
) {
810 array_push( $this->priorFlags
, $this->flags
);
812 $this->flags
&= ~
$flag;
815 public function restoreFlags( $state = self
::RESTORE_PRIOR
) {
816 if ( !$this->priorFlags
) {
820 if ( $state === self
::RESTORE_INITIAL
) {
821 $this->flags
= reset( $this->priorFlags
);
822 $this->priorFlags
= [];
824 $this->flags
= array_pop( $this->priorFlags
);
828 public function getFlag( $flag ) {
829 return (bool)( $this->flags
& $flag );
833 * @param string $name Class field name
835 * @deprecated Since 1.28
837 public function getProperty( $name ) {
841 public function getDomainID() {
842 return $this->currentDomain
->getId();
845 final public function getWikiID() {
846 return $this->getDomainID();
850 * Get information about an index into an object
851 * @param string $table Table name
852 * @param string $index Index name
853 * @param string $fname Calling function name
854 * @return mixed Database-specific index description class or false if the index does not exist
856 abstract function indexInfo( $table, $index, $fname = __METHOD__
);
859 * Wrapper for addslashes()
861 * @param string $s String to be slashed.
862 * @return string Slashed string.
864 abstract function strencode( $s );
867 * Set a custom error handler for logging errors during database connection
869 protected function installErrorHandler() {
870 $this->phpError
= false;
871 $this->htmlErrors
= ini_set( 'html_errors', '0' );
872 set_error_handler( [ $this, 'connectionErrorLogger' ] );
876 * Restore the previous error handler and return the last PHP error for this DB
878 * @return bool|string
880 protected function restoreErrorHandler() {
881 restore_error_handler();
882 if ( $this->htmlErrors
!== false ) {
883 ini_set( 'html_errors', $this->htmlErrors
);
886 return $this->getLastPHPError();
890 * @return string|bool Last PHP error for this DB (typically connection errors)
892 protected function getLastPHPError() {
893 if ( $this->phpError
) {
894 $error = preg_replace( '!\[<a.*</a>\]!', '', $this->phpError
);
895 $error = preg_replace( '!^.*?:\s?(.*)$!', '$1', $error );
904 * Error handler for logging errors during database connection
905 * This method should not be used outside of Database classes
908 * @param string $errstr
910 public function connectionErrorLogger( $errno, $errstr ) {
911 $this->phpError
= $errstr;
915 * Create a log context to pass to PSR-3 logger functions.
917 * @param array $extras Additional data to add to context
920 protected function getLogContext( array $extras = [] ) {
923 'db_server' => $this->server
,
924 'db_name' => $this->getDBname(),
925 'db_user' => $this->user
,
931 final public function close() {
932 $exception = null; // error to throw after disconnecting
934 $wasOpen = $this->opened
;
935 // This should mostly do nothing if the connection is already closed
937 // Roll back any dangling transaction first
938 if ( $this->trxLevel
) {
939 if ( $this->trxAtomicLevels
) {
940 // Cannot let incomplete atomic sections be committed
941 $levels = $this->flatAtomicSectionList();
942 $exception = new DBUnexpectedError(
944 __METHOD__
. ": atomic sections $levels are still open."
946 } elseif ( $this->trxAutomatic
) {
947 // Only the connection manager can commit non-empty DBO_TRX transactions
948 // (empty ones we can silently roll back)
949 if ( $this->writesOrCallbacksPending() ) {
950 $exception = new DBUnexpectedError(
953 ": mass commit/rollback of peer transaction required (DBO_TRX set)."
957 // Manual transactions should have been committed or rolled
958 // back, even if empty.
959 $exception = new DBUnexpectedError(
961 __METHOD__
. ": transaction is still open (from {$this->trxFname})."
965 if ( $this->trxEndCallbacksSuppressed
) {
966 $exception = $exception ?
: new DBUnexpectedError(
968 __METHOD__
. ': callbacks are suppressed; cannot properly commit.'
972 // Rollback the changes and run any callbacks as needed
973 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
976 // Close the actual connection in the binding handle
977 $closed = $this->closeConnection();
979 $closed = true; // already closed; nothing to do
983 $this->opened
= false;
985 // Throw any unexpected errors after having disconnected
986 if ( $exception instanceof Exception
) {
990 // Note that various subclasses call close() at the start of open(), which itself is
991 // called by replaceLostConnection(). In that case, just because onTransactionResolution()
992 // callbacks are pending does not mean that an exception should be thrown. Rather, they
993 // will be executed after the reconnection step.
995 // Sanity check that no callbacks are dangling
996 $fnames = $this->pendingWriteAndCallbackCallers();
998 throw new RuntimeException(
999 "Transaction callbacks are still pending:\n" . implode( ', ', $fnames )
1008 * Make sure there is an open connection handle (alive or not) as a sanity check
1010 * This guards against fatal errors to the binding handle not being defined
1011 * in cases where open() was never called or close() was already called
1013 * @throws DBUnexpectedError
1015 protected function assertHasConnectionHandle() {
1016 if ( !$this->isOpen() ) {
1017 throw new DBUnexpectedError( $this, "DB connection was already closed." );
1022 * Make sure that this server is not marked as a replica nor read-only as a sanity check
1024 * @throws DBUnexpectedError
1026 protected function assertIsWritableMaster() {
1027 if ( $this->getLBInfo( 'replica' ) === true ) {
1028 throw new DBUnexpectedError(
1030 'Write operations are not allowed on replica database connections.'
1033 $reason = $this->getReadOnlyReason();
1034 if ( $reason !== false ) {
1035 throw new DBReadOnlyError( $this, "Database is read-only: $reason" );
1040 * Closes underlying database connection
1042 * @return bool Whether connection was closed successfully
1044 abstract protected function closeConnection();
1047 * @deprecated since 1.32
1048 * @param string $error Fallback message, if none is given by DB
1049 * @throws DBConnectionError
1051 public function reportConnectionError( $error = 'Unknown error' ) {
1052 call_user_func( $this->deprecationLogger
, 'Use of ' . __METHOD__
. ' is deprecated.' );
1053 throw new DBConnectionError( $this, $this->lastError() ?
: $error );
1057 * Run a query and return a DBMS-dependent wrapper or boolean
1059 * For SELECT queries, this returns either:
1060 * - a) A driver-specific value/resource, only on success. This can be iterated
1061 * over by calling fetchObject()/fetchRow() until there are no more rows.
1062 * Alternatively, the result can be passed to resultObject() to obtain a
1063 * ResultWrapper instance which can then be iterated over via "foreach".
1064 * - b) False, on any query failure
1066 * For non-SELECT queries, this returns either:
1067 * - a) A driver-specific value/resource, only on success
1068 * - b) True, only on success (e.g. no meaningful result other than "OK")
1069 * - c) False, on any query failure
1071 * @param string $sql SQL query
1072 * @return mixed|bool An object, resource, or true on success; false on failure
1074 abstract protected function doQuery( $sql );
1077 * Determine whether a query writes to the DB. When in doubt, this returns true.
1081 * - Subsequent web requests should not need to wait for replication from
1082 * the master position seen by this web request, unless this request made
1083 * changes to the master. This is handled by ChronologyProtector by checking
1084 * doneWrites() at the end of the request. doneWrites() returns true if any
1085 * query set lastWriteTime; which query() does based on isWriteQuery().
1087 * - Reject write queries to replica DBs, in query().
1089 * @param string $sql
1092 protected function isWriteQuery( $sql ) {
1093 // BEGIN and COMMIT queries are considered read queries here.
1094 // Database backends and drivers (MySQL, MariaDB, php-mysqli) generally
1095 // treat these as write queries, in that their results have "affected rows"
1096 // as meta data as from writes, instead of "num rows" as from reads.
1097 // But, we treat them as read queries because when reading data (from
1098 // either replica or master) we use transactions to enable repeatable-read
1099 // snapshots, which ensures we get consistent results from the same snapshot
1100 // for all queries within a request. Use cases:
1101 // - Treating these as writes would trigger ChronologyProtector (see method doc).
1102 // - We use this method to reject writes to replicas, but we need to allow
1103 // use of transactions on replicas for read snapshots. This fine given
1104 // that transactions by themselves don't make changes, only actual writes
1105 // within the transaction matter, which we still detect.
1107 '/^(?:SELECT|BEGIN|ROLLBACK|COMMIT|SAVEPOINT|RELEASE|SET|SHOW|EXPLAIN|\(SELECT)\b/i',
1113 * @param string $sql
1114 * @return string|null
1116 protected function getQueryVerb( $sql ) {
1117 return preg_match( '/^\s*([a-z]+)/i', $sql, $m ) ?
strtoupper( $m[1] ) : null;
1121 * Determine whether a SQL statement is sensitive to isolation level.
1123 * A SQL statement is considered transactable if its result could vary
1124 * depending on the transaction isolation level. Operational commands
1125 * such as 'SET' and 'SHOW' are not considered to be transactable.
1127 * Main purpose: Used by query() to decide whether to begin a transaction
1128 * before the current query (in DBO_TRX mode, on by default).
1130 * @param string $sql
1133 protected function isTransactableQuery( $sql ) {
1135 $this->getQueryVerb( $sql ),
1136 [ 'BEGIN', 'ROLLBACK', 'COMMIT', 'SET', 'SHOW', 'CREATE', 'ALTER' ],
1142 * @param string $sql A SQL query
1143 * @param bool $pseudoPermanent Treat any table from CREATE TEMPORARY as pseudo-permanent
1144 * @return int|null A self::TEMP_* constant for temp table operations or null otherwise
1146 protected function registerTempTableWrite( $sql, $pseudoPermanent ) {
1147 static $qt = '[`"\']?(\w+)[`"\']?'; // quoted table
1150 '/^CREATE\s+TEMPORARY\s+TABLE\s+(?:IF\s+NOT\s+EXISTS\s+)?' . $qt . '/i',
1154 $type = $pseudoPermanent ? self
::TEMP_PSEUDO_PERMANENT
: self
::TEMP_NORMAL
;
1155 $this->sessionTempTables
[$matches[1]] = $type;
1158 } elseif ( preg_match(
1159 '/^DROP\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?' . $qt . '/i',
1163 $type = $this->sessionTempTables
[$matches[1]] ??
null;
1164 unset( $this->sessionTempTables
[$matches[1]] );
1167 } elseif ( preg_match(
1168 '/^TRUNCATE\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?' . $qt . '/i',
1172 return $this->sessionTempTables
[$matches[1]] ??
null;
1173 } elseif ( preg_match(
1174 '/^(?:(?:INSERT|REPLACE)\s+(?:\w+\s+)?INTO|UPDATE|DELETE\s+FROM)\s+' . $qt . '/i',
1178 return $this->sessionTempTables
[$matches[1]] ??
null;
1184 public function query( $sql, $fname = __METHOD__
, $flags = 0 ) {
1185 $this->assertTransactionStatus( $sql, $fname );
1186 $this->assertHasConnectionHandle();
1188 $flags = (int)$flags; // b/c; this field used to be a bool
1189 $ignoreErrors = $this->hasFlags( $flags, self
::QUERY_SILENCE_ERRORS
);
1190 $pseudoPermanent = $this->hasFlags( $flags, self
::QUERY_PSEUDO_PERMANENT
);
1192 $priorTransaction = $this->trxLevel
;
1193 $priorWritesPending = $this->writesOrCallbacksPending();
1194 $this->lastQuery
= $sql;
1196 if ( $this->isWriteQuery( $sql ) ) {
1197 # In theory, non-persistent writes are allowed in read-only mode, but due to things
1198 # like https://bugs.mysql.com/bug.php?id=33669 that might not work anyway...
1199 $this->assertIsWritableMaster();
1200 # Do not treat temporary table writes as "meaningful writes" that need committing.
1201 # Profile them as reads. Integration tests can override this behavior via $flags.
1202 $tableType = $this->registerTempTableWrite( $sql, $pseudoPermanent );
1203 $isEffectiveWrite = ( $tableType !== self
::TEMP_NORMAL
);
1205 $isEffectiveWrite = false;
1208 # Add trace comment to the begin of the sql string, right after the operator.
1209 # Or, for one-word queries (like "BEGIN" or COMMIT") add it to the end (T44598)
1210 $commentedSql = preg_replace( '/\s|$/', " /* $fname {$this->agent} */ ", $sql, 1 );
1212 # Send the query to the server and fetch any corresponding errors
1213 $ret = $this->attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname );
1214 $lastError = $this->lastError();
1215 $lastErrno = $this->lastErrno();
1217 $recoverableSR = false; // recoverable statement rollback?
1218 $recoverableCL = false; // recoverable connection loss?
1220 if ( $ret === false && $this->wasConnectionLoss() ) {
1221 # Check if no meaningful session state was lost
1222 $recoverableCL = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
1223 # Update session state tracking and try to restore the connection
1224 $reconnected = $this->replaceLostConnection( __METHOD__
);
1225 # Silently resend the query to the server if it is safe and possible
1226 if ( $recoverableCL && $reconnected ) {
1227 $ret = $this->attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname );
1228 $lastError = $this->lastError();
1229 $lastErrno = $this->lastErrno();
1231 if ( $ret === false && $this->wasConnectionLoss() ) {
1232 # Query probably causes disconnects; reconnect and do not re-run it
1233 $this->replaceLostConnection( __METHOD__
);
1235 $recoverableCL = false; // connection does not need recovering
1236 $recoverableSR = $this->wasKnownStatementRollbackError();
1240 $recoverableSR = $this->wasKnownStatementRollbackError();
1243 if ( $ret === false ) {
1244 if ( $priorTransaction ) {
1245 if ( $recoverableSR ) {
1246 # We're ignoring an error that caused just the current query to be aborted.
1247 # But log the cause so we can log a deprecation notice if a caller actually
1249 $this->trxStatusIgnoredCause
= [ $lastError, $lastErrno, $fname ];
1250 } elseif ( !$recoverableCL ) {
1251 # Either the query was aborted or all queries after BEGIN where aborted.
1252 # In the first case, the only options going forward are (a) ROLLBACK, or
1253 # (b) ROLLBACK TO SAVEPOINT (if one was set). If the later case, the only
1254 # option is ROLLBACK, since the snapshots would have been released.
1255 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
1256 $this->trxStatusCause
=
1257 $this->getQueryExceptionAndLog( $lastError, $lastErrno, $sql, $fname );
1258 $ignoreErrors = false; // cannot recover
1259 $this->trxStatusIgnoredCause
= null;
1263 $this->reportQueryError( $lastError, $lastErrno, $sql, $fname, $ignoreErrors );
1266 return $this->resultObject( $ret );
1270 * Wrapper for query() that also handles profiling, logging, and affected row count updates
1272 * @param string $sql Original SQL query
1273 * @param string $commentedSql SQL query with debugging/trace comment
1274 * @param bool $isEffectiveWrite Whether the query is a (non-temporary table) write
1275 * @param string $fname Name of the calling function
1276 * @return bool|ResultWrapper True for a successful write query, ResultWrapper
1277 * object for a successful read query, or false on failure
1279 private function attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname ) {
1280 $this->beginIfImplied( $sql, $fname );
1282 # Keep track of whether the transaction has write queries pending
1283 if ( $isEffectiveWrite ) {
1284 $this->lastWriteTime
= microtime( true );
1285 if ( $this->trxLevel
&& !$this->trxDoneWrites
) {
1286 $this->trxDoneWrites
= true;
1287 $this->trxProfiler
->transactionWritingIn(
1288 $this->server
, $this->getDomainID(), $this->trxShortId
);
1292 if ( $this->getFlag( self
::DBO_DEBUG
) ) {
1293 $this->queryLogger
->debug( "{$this->getDomainID()} {$commentedSql}" );
1296 $isMaster = !is_null( $this->getLBInfo( 'master' ) );
1297 # generalizeSQL() will probably cut down the query to reasonable
1298 # logging size most of the time. The substr is really just a sanity check.
1300 $queryProf = 'query-m: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1302 $queryProf = 'query: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1305 # Include query transaction state
1306 $queryProf .= $this->trxShortId ?
" [TRX#{$this->trxShortId}]" : "";
1308 $startTime = microtime( true );
1309 $ps = $this->profiler ?
( $this->profiler
)( $queryProf ) : null;
1310 $this->affectedRowCount
= null;
1311 $ret = $this->doQuery( $commentedSql );
1312 $this->affectedRowCount
= $this->affectedRows();
1313 unset( $ps ); // profile out (if set)
1314 $queryRuntime = max( microtime( true ) - $startTime, 0.0 );
1316 if ( $ret !== false ) {
1317 $this->lastPing
= $startTime;
1318 if ( $isEffectiveWrite && $this->trxLevel
) {
1319 $this->updateTrxWriteQueryTime( $sql, $queryRuntime, $this->affectedRows() );
1320 $this->trxWriteCallers
[] = $fname;
1324 if ( $sql === self
::PING_QUERY
) {
1325 $this->rttEstimate
= $queryRuntime;
1328 $this->trxProfiler
->recordQueryCompletion(
1332 $isEffectiveWrite ?
$this->affectedRows() : $this->numRows( $ret )
1334 $this->queryLogger
->debug( $sql, [
1336 'master' => $isMaster,
1337 'runtime' => $queryRuntime,
1344 * Start an implicit transaction if DBO_TRX is enabled and no transaction is active
1346 * @param string $sql
1347 * @param string $fname
1349 private function beginIfImplied( $sql, $fname ) {
1352 $this->getFlag( self
::DBO_TRX
) &&
1353 $this->isTransactableQuery( $sql )
1355 $this->begin( __METHOD__
. " ($fname)", self
::TRANSACTION_INTERNAL
);
1356 $this->trxAutomatic
= true;
1361 * Update the estimated run-time of a query, not counting large row lock times
1363 * LoadBalancer can be set to rollback transactions that will create huge replication
1364 * lag. It bases this estimate off of pendingWriteQueryDuration(). Certain simple
1365 * queries, like inserting a row can take a long time due to row locking. This method
1366 * uses some simple heuristics to discount those cases.
1368 * @param string $sql A SQL write query
1369 * @param float $runtime Total runtime, including RTT
1370 * @param int $affected Affected row count
1372 private function updateTrxWriteQueryTime( $sql, $runtime, $affected ) {
1373 // Whether this is indicative of replica DB runtime (except for RBR or ws_repl)
1374 $indicativeOfReplicaRuntime = true;
1375 if ( $runtime > self
::SLOW_WRITE_SEC
) {
1376 $verb = $this->getQueryVerb( $sql );
1377 // insert(), upsert(), replace() are fast unless bulky in size or blocked on locks
1378 if ( $verb === 'INSERT' ) {
1379 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
;
1380 } elseif ( $verb === 'REPLACE' ) {
1381 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
/ 2;
1385 $this->trxWriteDuration +
= $runtime;
1386 $this->trxWriteQueryCount +
= 1;
1387 $this->trxWriteAffectedRows +
= $affected;
1388 if ( $indicativeOfReplicaRuntime ) {
1389 $this->trxWriteAdjDuration +
= $runtime;
1390 $this->trxWriteAdjQueryCount +
= 1;
1395 * Error out if the DB is not in a valid state for a query via query()
1397 * @param string $sql
1398 * @param string $fname
1399 * @throws DBTransactionStateError
1401 private function assertTransactionStatus( $sql, $fname ) {
1402 $verb = $this->getQueryVerb( $sql );
1403 if ( $verb === 'USE' ) {
1404 throw new DBUnexpectedError( $this, "Got USE query; use selectDomain() instead." );
1407 if ( $verb === 'ROLLBACK' ) { // transaction/savepoint
1411 if ( $this->trxStatus
< self
::STATUS_TRX_OK
) {
1412 throw new DBTransactionStateError(
1414 "Cannot execute query from $fname while transaction status is ERROR.",
1416 $this->trxStatusCause
1418 } elseif ( $this->trxStatus
=== self
::STATUS_TRX_OK
&& $this->trxStatusIgnoredCause
) {
1419 list( $iLastError, $iLastErrno, $iFname ) = $this->trxStatusIgnoredCause
;
1420 call_user_func( $this->deprecationLogger
,
1421 "Caller from $fname ignored an error originally raised from $iFname: " .
1422 "[$iLastErrno] $iLastError"
1424 $this->trxStatusIgnoredCause
= null;
1428 public function assertNoOpenTransactions() {
1429 if ( $this->explicitTrxActive() ) {
1430 throw new DBTransactionError(
1432 "Explicit transaction still active. A caller may have caught an error. "
1433 . "Open transactions: " . $this->flatAtomicSectionList()
1439 * Determine whether it is safe to retry queries after a database connection is lost
1441 * @param string $sql SQL query
1442 * @param bool $priorWritesPending Whether there is a transaction open with
1443 * possible write queries or transaction pre-commit/idle callbacks
1444 * waiting on it to finish.
1445 * @return bool True if it is safe to retry the query, false otherwise
1447 private function canRecoverFromDisconnect( $sql, $priorWritesPending ) {
1448 # Transaction dropped; this can mean lost writes, or REPEATABLE-READ snapshots.
1449 # Dropped connections also mean that named locks are automatically released.
1450 # Only allow error suppression in autocommit mode or when the lost transaction
1451 # didn't matter anyway (aside from DBO_TRX snapshot loss).
1452 if ( $this->namedLocksHeld
) {
1453 return false; // possible critical section violation
1454 } elseif ( $this->sessionTempTables
) {
1455 return false; // tables might be queried latter
1456 } elseif ( $sql === 'COMMIT' ) {
1457 return !$priorWritesPending; // nothing written anyway? (T127428)
1458 } elseif ( $sql === 'ROLLBACK' ) {
1459 return true; // transaction lost...which is also what was requested :)
1460 } elseif ( $this->explicitTrxActive() ) {
1461 return false; // don't drop atomocity and explicit snapshots
1462 } elseif ( $priorWritesPending ) {
1463 return false; // prior writes lost from implicit transaction
1470 * Clean things up after session (and thus transaction) loss before reconnect
1472 private function handleSessionLossPreconnect() {
1473 // Clean up tracking of session-level things...
1474 // https://dev.mysql.com/doc/refman/5.7/en/implicit-commit.html
1475 // https://www.postgresql.org/docs/9.2/static/sql-createtable.html (ignoring ON COMMIT)
1476 $this->sessionTempTables
= [];
1477 // https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1478 // https://www.postgresql.org/docs/9.4/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1479 $this->namedLocksHeld
= [];
1480 // Session loss implies transaction loss
1481 $this->trxLevel
= 0;
1482 $this->trxAtomicCounter
= 0;
1483 $this->trxIdleCallbacks
= []; // T67263; transaction already lost
1484 $this->trxPreCommitCallbacks
= []; // T67263; transaction already lost
1485 // @note: leave trxRecurringCallbacks in place
1486 if ( $this->trxDoneWrites
) {
1487 $this->trxProfiler
->transactionWritingOut(
1489 $this->getDomainID(),
1491 $this->pendingWriteQueryDuration( self
::ESTIMATE_TOTAL
),
1492 $this->trxWriteAffectedRows
1498 * Clean things up after session (and thus transaction) loss after reconnect
1500 private function handleSessionLossPostconnect() {
1502 // Handle callbacks in trxEndCallbacks, e.g. onTransactionResolution().
1503 // If callback suppression is set then the array will remain unhandled.
1504 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
1505 } catch ( Exception
$ex ) {
1506 // Already logged; move on...
1509 // Handle callbacks in trxRecurringCallbacks, e.g. setTransactionListener()
1510 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
1511 } catch ( Exception
$ex ) {
1512 // Already logged; move on...
1517 * Checks whether the cause of the error is detected to be a timeout.
1519 * It returns false by default, and not all engines support detecting this yet.
1520 * If this returns false, it will be treated as a generic query error.
1522 * @param string $error Error text
1523 * @param int $errno Error number
1526 protected function wasQueryTimeout( $error, $errno ) {
1531 * Report a query error. Log the error, and if neither the object ignore
1532 * flag nor the $ignoreErrors flag is set, throw a DBQueryError.
1534 * @param string $error
1536 * @param string $sql
1537 * @param string $fname
1538 * @param bool $ignoreErrors
1539 * @throws DBQueryError
1541 public function reportQueryError( $error, $errno, $sql, $fname, $ignoreErrors = false ) {
1542 if ( $ignoreErrors ) {
1543 $this->queryLogger
->debug( "SQL ERROR (ignored): $error\n" );
1545 $exception = $this->getQueryExceptionAndLog( $error, $errno, $sql, $fname );
1552 * @param string $error
1553 * @param string|int $errno
1554 * @param string $sql
1555 * @param string $fname
1558 private function getQueryExceptionAndLog( $error, $errno, $sql, $fname ) {
1559 $sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
1560 $this->queryLogger
->error(
1561 "{fname}\t{db_server}\t{errno}\t{error}\t{sql1line}",
1562 $this->getLogContext( [
1563 'method' => __METHOD__
,
1566 'sql1line' => $sql1line,
1568 'trace' => ( new RuntimeException() )->getTraceAsString()
1571 $this->queryLogger
->debug( "SQL ERROR: " . $error . "\n" );
1572 $wasQueryTimeout = $this->wasQueryTimeout( $error, $errno );
1573 if ( $wasQueryTimeout ) {
1574 $e = new DBQueryTimeoutError( $this, $error, $errno, $sql, $fname );
1576 $e = new DBQueryError( $this, $error, $errno, $sql, $fname );
1582 public function freeResult( $res ) {
1585 public function selectField(
1586 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1588 if ( $var === '*' ) { // sanity
1589 throw new DBUnexpectedError( $this, "Cannot use a * field: got '$var'" );
1592 if ( !is_array( $options ) ) {
1593 $options = [ $options ];
1596 $options['LIMIT'] = 1;
1598 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1599 if ( $res === false ||
!$this->numRows( $res ) ) {
1603 $row = $this->fetchRow( $res );
1605 if ( $row !== false ) {
1606 return reset( $row );
1612 public function selectFieldValues(
1613 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1615 if ( $var === '*' ) { // sanity
1616 throw new DBUnexpectedError( $this, "Cannot use a * field" );
1617 } elseif ( !is_string( $var ) ) { // sanity
1618 throw new DBUnexpectedError( $this, "Cannot use an array of fields" );
1621 if ( !is_array( $options ) ) {
1622 $options = [ $options ];
1625 $res = $this->select( $table, [ 'value' => $var ], $cond, $fname, $options, $join_conds );
1626 if ( $res === false ) {
1631 foreach ( $res as $row ) {
1632 $values[] = $row->value
;
1639 * Returns an optional USE INDEX clause to go after the table, and a
1640 * string to go at the end of the query.
1642 * @param array $options Associative array of options to be turned into
1643 * an SQL query, valid keys are listed in the function.
1645 * @see Database::select()
1647 protected function makeSelectOptions( $options ) {
1648 $preLimitTail = $postLimitTail = '';
1653 foreach ( $options as $key => $option ) {
1654 if ( is_numeric( $key ) ) {
1655 $noKeyOptions[$option] = true;
1659 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1661 $preLimitTail .= $this->makeOrderBy( $options );
1663 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1664 $postLimitTail .= ' FOR UPDATE';
1667 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1668 $postLimitTail .= ' LOCK IN SHARE MODE';
1671 if ( isset( $noKeyOptions['DISTINCT'] ) ||
isset( $noKeyOptions['DISTINCTROW'] ) ) {
1672 $startOpts .= 'DISTINCT';
1675 # Various MySQL extensions
1676 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) {
1677 $startOpts .= ' /*! STRAIGHT_JOIN */';
1680 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) {
1681 $startOpts .= ' HIGH_PRIORITY';
1684 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) {
1685 $startOpts .= ' SQL_BIG_RESULT';
1688 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) {
1689 $startOpts .= ' SQL_BUFFER_RESULT';
1692 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) {
1693 $startOpts .= ' SQL_SMALL_RESULT';
1696 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) {
1697 $startOpts .= ' SQL_CALC_FOUND_ROWS';
1700 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) {
1701 $startOpts .= ' SQL_CACHE';
1704 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) {
1705 $startOpts .= ' SQL_NO_CACHE';
1708 if ( isset( $options['USE INDEX'] ) && is_string( $options['USE INDEX'] ) ) {
1709 $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1713 if ( isset( $options['IGNORE INDEX'] ) && is_string( $options['IGNORE INDEX'] ) ) {
1714 $ignoreIndex = $this->ignoreIndexClause( $options['IGNORE INDEX'] );
1719 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1723 * Returns an optional GROUP BY with an optional HAVING
1725 * @param array $options Associative array of options
1727 * @see Database::select()
1730 protected function makeGroupByWithHaving( $options ) {
1732 if ( isset( $options['GROUP BY'] ) ) {
1733 $gb = is_array( $options['GROUP BY'] )
1734 ?
implode( ',', $options['GROUP BY'] )
1735 : $options['GROUP BY'];
1736 $sql .= ' GROUP BY ' . $gb;
1738 if ( isset( $options['HAVING'] ) ) {
1739 $having = is_array( $options['HAVING'] )
1740 ?
$this->makeList( $options['HAVING'], self
::LIST_AND
)
1741 : $options['HAVING'];
1742 $sql .= ' HAVING ' . $having;
1749 * Returns an optional ORDER BY
1751 * @param array $options Associative array of options
1753 * @see Database::select()
1756 protected function makeOrderBy( $options ) {
1757 if ( isset( $options['ORDER BY'] ) ) {
1758 $ob = is_array( $options['ORDER BY'] )
1759 ?
implode( ',', $options['ORDER BY'] )
1760 : $options['ORDER BY'];
1762 return ' ORDER BY ' . $ob;
1768 public function select(
1769 $table, $vars, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1771 $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
1773 return $this->query( $sql, $fname );
1776 public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__
,
1777 $options = [], $join_conds = []
1779 if ( is_array( $vars ) ) {
1780 $fields = implode( ',', $this->fieldNamesWithAlias( $vars ) );
1785 $options = (array)$options;
1786 $useIndexes = ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1787 ?
$options['USE INDEX']
1790 isset( $options['IGNORE INDEX'] ) &&
1791 is_array( $options['IGNORE INDEX'] )
1793 ?
$options['IGNORE INDEX']
1797 $this->selectOptionsIncludeLocking( $options ) &&
1798 $this->selectFieldsOrOptionsAggregate( $vars, $options )
1800 // Some DB types (postgres/oracle) disallow FOR UPDATE with aggregate
1801 // functions. Discourage use of such queries to encourage compatibility.
1803 $this->deprecationLogger
,
1804 __METHOD__
. ": aggregation used with a locking SELECT ($fname)."
1808 if ( is_array( $table ) ) {
1810 $this->tableNamesWithIndexClauseOrJOIN(
1811 $table, $useIndexes, $ignoreIndexes, $join_conds );
1812 } elseif ( $table != '' ) {
1814 $this->tableNamesWithIndexClauseOrJOIN(
1815 [ $table ], $useIndexes, $ignoreIndexes, [] );
1820 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ) =
1821 $this->makeSelectOptions( $options );
1823 if ( is_array( $conds ) ) {
1824 $conds = $this->makeList( $conds, self
::LIST_AND
);
1827 if ( $conds === null ||
$conds === false ) {
1828 $this->queryLogger
->warning(
1832 . ' with incorrect parameters: $conds must be a string or an array'
1837 if ( $conds === '' ||
$conds === '*' ) {
1838 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex $preLimitTail";
1839 } elseif ( is_string( $conds ) ) {
1840 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex " .
1841 "WHERE $conds $preLimitTail";
1843 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
1846 if ( isset( $options['LIMIT'] ) ) {
1847 $sql = $this->limitResult( $sql, $options['LIMIT'],
1848 $options['OFFSET'] ??
false );
1850 $sql = "$sql $postLimitTail";
1852 if ( isset( $options['EXPLAIN'] ) ) {
1853 $sql = 'EXPLAIN ' . $sql;
1859 public function selectRow( $table, $vars, $conds, $fname = __METHOD__
,
1860 $options = [], $join_conds = []
1862 $options = (array)$options;
1863 $options['LIMIT'] = 1;
1864 $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
1866 if ( $res === false ) {
1870 if ( !$this->numRows( $res ) ) {
1874 $obj = $this->fetchObject( $res );
1879 public function estimateRowCount(
1880 $table, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1882 $conds = $this->normalizeConditions( $conds, $fname );
1883 $column = $this->extractSingleFieldFromList( $var );
1884 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1885 $conds[] = "$column IS NOT NULL";
1888 $res = $this->select(
1889 $table, [ 'rowcount' => 'COUNT(*)' ], $conds, $fname, $options, $join_conds
1891 $row = $res ?
$this->fetchRow( $res ) : [];
1893 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1896 public function selectRowCount(
1897 $tables, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1899 $conds = $this->normalizeConditions( $conds, $fname );
1900 $column = $this->extractSingleFieldFromList( $var );
1901 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1902 $conds[] = "$column IS NOT NULL";
1905 $res = $this->select(
1907 'tmp_count' => $this->buildSelectSubquery(
1916 [ 'rowcount' => 'COUNT(*)' ],
1920 $row = $res ?
$this->fetchRow( $res ) : [];
1922 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1926 * @param string|array $options
1929 private function selectOptionsIncludeLocking( $options ) {
1930 $options = (array)$options;
1931 foreach ( [ 'FOR UPDATE', 'LOCK IN SHARE MODE' ] as $lock ) {
1932 if ( in_array( $lock, $options, true ) ) {
1941 * @param array|string $fields
1942 * @param array|string $options
1945 private function selectFieldsOrOptionsAggregate( $fields, $options ) {
1946 foreach ( (array)$options as $key => $value ) {
1947 if ( is_string( $key ) ) {
1948 if ( preg_match( '/^(?:GROUP BY|HAVING)$/i', $key ) ) {
1951 } elseif ( is_string( $value ) ) {
1952 if ( preg_match( '/^(?:DISTINCT|DISTINCTROW)$/i', $value ) ) {
1958 $regex = '/^(?:COUNT|MIN|MAX|SUM|GROUP_CONCAT|LISTAGG|ARRAY_AGG)\s*\\(/i';
1959 foreach ( (array)$fields as $field ) {
1960 if ( is_string( $field ) && preg_match( $regex, $field ) ) {
1969 * @param array|string $conds
1970 * @param string $fname
1973 final protected function normalizeConditions( $conds, $fname ) {
1974 if ( $conds === null ||
$conds === false ) {
1975 $this->queryLogger
->warning(
1979 . ' with incorrect parameters: $conds must be a string or an array'
1984 if ( !is_array( $conds ) ) {
1985 $conds = ( $conds === '' ) ?
[] : [ $conds ];
1992 * @param array|string $var Field parameter in the style of select()
1993 * @return string|null Column name or null; ignores aliases
1994 * @throws DBUnexpectedError Errors out if multiple columns are given
1996 final protected function extractSingleFieldFromList( $var ) {
1997 if ( is_array( $var ) ) {
2000 } elseif ( count( $var ) == 1 ) {
2001 $column = $var[0] ??
reset( $var );
2003 throw new DBUnexpectedError( $this, __METHOD__
. ': got multiple columns.' );
2012 public function lockForUpdate(
2013 $table, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
2015 if ( !$this->trxLevel
&& !$this->getFlag( self
::DBO_TRX
) ) {
2016 throw new DBUnexpectedError(
2018 __METHOD__
. ': no transaction is active nor is DBO_TRX set'
2022 $options = (array)$options;
2023 $options[] = 'FOR UPDATE';
2025 return $this->selectRowCount( $table, '*', $conds, $fname, $options, $join_conds );
2029 * Removes most variables from an SQL query and replaces them with X or N for numbers.
2030 * It's only slightly flawed. Don't use for anything important.
2032 * @param string $sql A SQL Query
2036 protected static function generalizeSQL( $sql ) {
2037 # This does the same as the regexp below would do, but in such a way
2038 # as to avoid crashing php on some large strings.
2039 # $sql = preg_replace( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql );
2041 $sql = str_replace( "\\\\", '', $sql );
2042 $sql = str_replace( "\\'", '', $sql );
2043 $sql = str_replace( "\\\"", '', $sql );
2044 $sql = preg_replace( "/'.*'/s", "'X'", $sql );
2045 $sql = preg_replace( '/".*"/s', "'X'", $sql );
2047 # All newlines, tabs, etc replaced by single space
2048 $sql = preg_replace( '/\s+/', ' ', $sql );
2051 # except the ones surrounded by characters, e.g. l10n
2052 $sql = preg_replace( '/-?\d+(,-?\d+)+/s', 'N,...,N', $sql );
2053 $sql = preg_replace( '/(?<![a-zA-Z])-?\d+(?![a-zA-Z])/s', 'N', $sql );
2058 public function fieldExists( $table, $field, $fname = __METHOD__
) {
2059 $info = $this->fieldInfo( $table, $field );
2064 public function indexExists( $table, $index, $fname = __METHOD__
) {
2065 if ( !$this->tableExists( $table ) ) {
2069 $info = $this->indexInfo( $table, $index, $fname );
2070 if ( is_null( $info ) ) {
2073 return $info !== false;
2077 abstract public function tableExists( $table, $fname = __METHOD__
);
2079 public function indexUnique( $table, $index ) {
2080 $indexInfo = $this->indexInfo( $table, $index );
2082 if ( !$indexInfo ) {
2086 return !$indexInfo[0]->Non_unique
;
2090 * Helper for Database::insert().
2092 * @param array $options
2095 protected function makeInsertOptions( $options ) {
2096 return implode( ' ', $options );
2099 public function insert( $table, $a, $fname = __METHOD__
, $options = [] ) {
2100 # No rows to insert, easy just return now
2101 if ( !count( $a ) ) {
2105 $table = $this->tableName( $table );
2107 if ( !is_array( $options ) ) {
2108 $options = [ $options ];
2111 $options = $this->makeInsertOptions( $options );
2113 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
2115 $keys = array_keys( $a[0] );
2118 $keys = array_keys( $a );
2121 $sql = 'INSERT ' . $options .
2122 " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
2126 foreach ( $a as $row ) {
2132 $sql .= '(' . $this->makeList( $row ) . ')';
2135 $sql .= '(' . $this->makeList( $a ) . ')';
2138 $this->query( $sql, $fname );
2144 * Make UPDATE options array for Database::makeUpdateOptions
2146 * @param array $options
2149 protected function makeUpdateOptionsArray( $options ) {
2150 if ( !is_array( $options ) ) {
2151 $options = [ $options ];
2156 if ( in_array( 'IGNORE', $options ) ) {
2164 * Make UPDATE options for the Database::update function
2166 * @param array $options The options passed to Database::update
2169 protected function makeUpdateOptions( $options ) {
2170 $opts = $this->makeUpdateOptionsArray( $options );
2172 return implode( ' ', $opts );
2175 public function update( $table, $values, $conds, $fname = __METHOD__
, $options = [] ) {
2176 $table = $this->tableName( $table );
2177 $opts = $this->makeUpdateOptions( $options );
2178 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, self
::LIST_SET
);
2180 if ( $conds !== [] && $conds !== '*' ) {
2181 $sql .= " WHERE " . $this->makeList( $conds, self
::LIST_AND
);
2184 $this->query( $sql, $fname );
2189 public function makeList( $a, $mode = self
::LIST_COMMA
) {
2190 if ( !is_array( $a ) ) {
2191 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
2197 foreach ( $a as $field => $value ) {
2199 if ( $mode == self
::LIST_AND
) {
2201 } elseif ( $mode == self
::LIST_OR
) {
2210 if ( ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_numeric( $field ) ) {
2211 $list .= "($value)";
2212 } elseif ( $mode == self
::LIST_SET
&& is_numeric( $field ) ) {
2215 ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_array( $value )
2217 // Remove null from array to be handled separately if found
2218 $includeNull = false;
2219 foreach ( array_keys( $value, null, true ) as $nullKey ) {
2220 $includeNull = true;
2221 unset( $value[$nullKey] );
2223 if ( count( $value ) == 0 && !$includeNull ) {
2224 throw new InvalidArgumentException(
2225 __METHOD__
. ": empty input for field $field" );
2226 } elseif ( count( $value ) == 0 ) {
2227 // only check if $field is null
2228 $list .= "$field IS NULL";
2230 // IN clause contains at least one valid element
2231 if ( $includeNull ) {
2232 // Group subconditions to ensure correct precedence
2235 if ( count( $value ) == 1 ) {
2236 // Special-case single values, as IN isn't terribly efficient
2237 // Don't necessarily assume the single key is 0; we don't
2238 // enforce linear numeric ordering on other arrays here.
2239 $value = array_values( $value )[0];
2240 $list .= $field . " = " . $this->addQuotes( $value );
2242 $list .= $field . " IN (" . $this->makeList( $value ) . ") ";
2244 // if null present in array, append IS NULL
2245 if ( $includeNull ) {
2246 $list .= " OR $field IS NULL)";
2249 } elseif ( $value === null ) {
2250 if ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) {
2251 $list .= "$field IS ";
2252 } elseif ( $mode == self
::LIST_SET
) {
2253 $list .= "$field = ";
2258 $mode == self
::LIST_AND ||
$mode == self
::LIST_OR ||
$mode == self
::LIST_SET
2260 $list .= "$field = ";
2262 $list .= $mode == self
::LIST_NAMES ?
$value : $this->addQuotes( $value );
2269 public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
2272 foreach ( $data as $base => $sub ) {
2273 if ( count( $sub ) ) {
2274 $conds[] = $this->makeList(
2275 [ $baseKey => $base, $subKey => array_keys( $sub ) ],
2281 return $this->makeList( $conds, self
::LIST_OR
);
2283 // Nothing to search for...
2288 public function aggregateValue( $valuedata, $valuename = 'value' ) {
2292 public function bitNot( $field ) {
2296 public function bitAnd( $fieldLeft, $fieldRight ) {
2297 return "($fieldLeft & $fieldRight)";
2300 public function bitOr( $fieldLeft, $fieldRight ) {
2301 return "($fieldLeft | $fieldRight)";
2304 public function buildConcat( $stringList ) {
2305 return 'CONCAT(' . implode( ',', $stringList ) . ')';
2308 public function buildGroupConcatField(
2309 $delim, $table, $field, $conds = '', $join_conds = []
2311 $fld = "GROUP_CONCAT($field SEPARATOR " . $this->addQuotes( $delim ) . ')';
2313 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
2316 public function buildSubstring( $input, $startPosition, $length = null ) {
2317 $this->assertBuildSubstringParams( $startPosition, $length );
2318 $functionBody = "$input FROM $startPosition";
2319 if ( $length !== null ) {
2320 $functionBody .= " FOR $length";
2322 return 'SUBSTRING(' . $functionBody . ')';
2326 * Check type and bounds for parameters to self::buildSubstring()
2328 * All supported databases have substring functions that behave the same for
2329 * positive $startPosition and non-negative $length, but behaviors differ when
2330 * given 0 or negative $startPosition or negative $length. The simplest
2331 * solution to that is to just forbid those values.
2333 * @param int $startPosition
2334 * @param int|null $length
2337 protected function assertBuildSubstringParams( $startPosition, $length ) {
2338 if ( !is_int( $startPosition ) ||
$startPosition <= 0 ) {
2339 throw new InvalidArgumentException(
2340 '$startPosition must be a positive integer'
2343 if ( !( is_int( $length ) && $length >= 0 ||
$length === null ) ) {
2344 throw new InvalidArgumentException(
2345 '$length must be null or an integer greater than or equal to 0'
2350 public function buildStringCast( $field ) {
2351 // In theory this should work for any standards-compliant
2352 // SQL implementation, although it may not be the best way to do it.
2353 return "CAST( $field AS CHARACTER )";
2356 public function buildIntegerCast( $field ) {
2357 return 'CAST( ' . $field . ' AS INTEGER )';
2360 public function buildSelectSubquery(
2361 $table, $vars, $conds = '', $fname = __METHOD__
,
2362 $options = [], $join_conds = []
2364 return new Subquery(
2365 $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds )
2369 public function databasesAreIndependent() {
2373 final public function selectDB( $db ) {
2374 $this->selectDomain( new DatabaseDomain(
2376 $this->currentDomain
->getSchema(),
2377 $this->currentDomain
->getTablePrefix()
2383 final public function selectDomain( $domain ) {
2384 $this->doSelectDomain( DatabaseDomain
::newFromId( $domain ) );
2387 protected function doSelectDomain( DatabaseDomain
$domain ) {
2388 $this->currentDomain
= $domain;
2391 public function getDBname() {
2392 return $this->currentDomain
->getDatabase();
2395 public function getServer() {
2396 return $this->server
;
2399 public function tableName( $name, $format = 'quoted' ) {
2400 if ( $name instanceof Subquery
) {
2401 throw new DBUnexpectedError(
2403 __METHOD__
. ': got Subquery instance when expecting a string.'
2407 # Skip the entire process when we have a string quoted on both ends.
2408 # Note that we check the end so that we will still quote any use of
2409 # use of `database`.table. But won't break things if someone wants
2410 # to query a database table with a dot in the name.
2411 if ( $this->isQuotedIdentifier( $name ) ) {
2415 # Lets test for any bits of text that should never show up in a table
2416 # name. Basically anything like JOIN or ON which are actually part of
2417 # SQL queries, but may end up inside of the table value to combine
2418 # sql. Such as how the API is doing.
2419 # Note that we use a whitespace test rather than a \b test to avoid
2420 # any remote case where a word like on may be inside of a table name
2421 # surrounded by symbols which may be considered word breaks.
2422 if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) {
2423 $this->queryLogger
->warning(
2424 __METHOD__
. ": use of subqueries is not supported this way.",
2425 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
2431 # Split database and table into proper variables.
2432 list( $database, $schema, $prefix, $table ) = $this->qualifiedTableComponents( $name );
2434 # Quote $table and apply the prefix if not quoted.
2435 # $tableName might be empty if this is called from Database::replaceVars()
2436 $tableName = "{$prefix}{$table}";
2437 if ( $format === 'quoted'
2438 && !$this->isQuotedIdentifier( $tableName )
2439 && $tableName !== ''
2441 $tableName = $this->addIdentifierQuotes( $tableName );
2444 # Quote $schema and $database and merge them with the table name if needed
2445 $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
2446 $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
2452 * Get the table components needed for a query given the currently selected database
2454 * @param string $name Table name in the form of db.schema.table, db.table, or table
2455 * @return array (DB name or "" for default, schema name, table prefix, table name)
2457 protected function qualifiedTableComponents( $name ) {
2458 # We reverse the explode so that database.table and table both output the correct table.
2459 $dbDetails = explode( '.', $name, 3 );
2460 if ( count( $dbDetails ) == 3 ) {
2461 list( $database, $schema, $table ) = $dbDetails;
2462 # We don't want any prefix added in this case
2464 } elseif ( count( $dbDetails ) == 2 ) {
2465 list( $database, $table ) = $dbDetails;
2466 # We don't want any prefix added in this case
2468 # In dbs that support it, $database may actually be the schema
2469 # but that doesn't affect any of the functionality here
2472 list( $table ) = $dbDetails;
2473 if ( isset( $this->tableAliases
[$table] ) ) {
2474 $database = $this->tableAliases
[$table]['dbname'];
2475 $schema = is_string( $this->tableAliases
[$table]['schema'] )
2476 ?
$this->tableAliases
[$table]['schema']
2477 : $this->relationSchemaQualifier();
2478 $prefix = is_string( $this->tableAliases
[$table]['prefix'] )
2479 ?
$this->tableAliases
[$table]['prefix']
2480 : $this->tablePrefix();
2483 $schema = $this->relationSchemaQualifier(); # Default schema
2484 $prefix = $this->tablePrefix(); # Default prefix
2488 return [ $database, $schema, $prefix, $table ];
2492 * @param string|null $namespace Database or schema
2493 * @param string $relation Name of table, view, sequence, etc...
2494 * @param string $format One of (raw, quoted)
2495 * @return string Relation name with quoted and merged $namespace as needed
2497 private function prependDatabaseOrSchema( $namespace, $relation, $format ) {
2498 if ( strlen( $namespace ) ) {
2499 if ( $format === 'quoted' && !$this->isQuotedIdentifier( $namespace ) ) {
2500 $namespace = $this->addIdentifierQuotes( $namespace );
2502 $relation = $namespace . '.' . $relation;
2508 public function tableNames() {
2509 $inArray = func_get_args();
2512 foreach ( $inArray as $name ) {
2513 $retVal[$name] = $this->tableName( $name );
2519 public function tableNamesN() {
2520 $inArray = func_get_args();
2523 foreach ( $inArray as $name ) {
2524 $retVal[] = $this->tableName( $name );
2531 * Get an aliased table name
2533 * This returns strings like "tableName AS newTableName" for aliased tables
2534 * and "(SELECT * from tableA) newTablename" for subqueries (e.g. derived tables)
2536 * @see Database::tableName()
2537 * @param string|Subquery $table Table name or object with a 'sql' field
2538 * @param string|bool $alias Table alias (optional)
2539 * @return string SQL name for aliased table. Will not alias a table to its own name
2541 protected function tableNameWithAlias( $table, $alias = false ) {
2542 if ( is_string( $table ) ) {
2543 $quotedTable = $this->tableName( $table );
2544 } elseif ( $table instanceof Subquery
) {
2545 $quotedTable = (string)$table;
2547 throw new InvalidArgumentException( "Table must be a string or Subquery." );
2550 if ( $alias === false ||
$alias === $table ) {
2551 if ( $table instanceof Subquery
) {
2552 throw new InvalidArgumentException( "Subquery table missing alias." );
2555 return $quotedTable;
2557 return $quotedTable . ' ' . $this->addIdentifierQuotes( $alias );
2562 * Gets an array of aliased table names
2564 * @param array $tables [ [alias] => table ]
2565 * @return string[] See tableNameWithAlias()
2567 protected function tableNamesWithAlias( $tables ) {
2569 foreach ( $tables as $alias => $table ) {
2570 if ( is_numeric( $alias ) ) {
2573 $retval[] = $this->tableNameWithAlias( $table, $alias );
2580 * Get an aliased field name
2581 * e.g. fieldName AS newFieldName
2583 * @param string $name Field name
2584 * @param string|bool $alias Alias (optional)
2585 * @return string SQL name for aliased field. Will not alias a field to its own name
2587 protected function fieldNameWithAlias( $name, $alias = false ) {
2588 if ( !$alias ||
(string)$alias === (string)$name ) {
2591 return $name . ' AS ' . $this->addIdentifierQuotes( $alias ); // PostgreSQL needs AS
2596 * Gets an array of aliased field names
2598 * @param array $fields [ [alias] => field ]
2599 * @return string[] See fieldNameWithAlias()
2601 protected function fieldNamesWithAlias( $fields ) {
2603 foreach ( $fields as $alias => $field ) {
2604 if ( is_numeric( $alias ) ) {
2607 $retval[] = $this->fieldNameWithAlias( $field, $alias );
2614 * Get the aliased table name clause for a FROM clause
2615 * which might have a JOIN and/or USE INDEX or IGNORE INDEX clause
2617 * @param array $tables ( [alias] => table )
2618 * @param array $use_index Same as for select()
2619 * @param array $ignore_index Same as for select()
2620 * @param array $join_conds Same as for select()
2623 protected function tableNamesWithIndexClauseOrJOIN(
2624 $tables, $use_index = [], $ignore_index = [], $join_conds = []
2628 $use_index = (array)$use_index;
2629 $ignore_index = (array)$ignore_index;
2630 $join_conds = (array)$join_conds;
2632 foreach ( $tables as $alias => $table ) {
2633 if ( !is_string( $alias ) ) {
2634 // No alias? Set it equal to the table name
2638 if ( is_array( $table ) ) {
2639 // A parenthesized group
2640 if ( count( $table ) > 1 ) {
2641 $joinedTable = '(' .
2642 $this->tableNamesWithIndexClauseOrJOIN(
2643 $table, $use_index, $ignore_index, $join_conds ) . ')';
2646 $innerTable = reset( $table );
2647 $innerAlias = key( $table );
2648 $joinedTable = $this->tableNameWithAlias(
2650 is_string( $innerAlias ) ?
$innerAlias : $innerTable
2654 $joinedTable = $this->tableNameWithAlias( $table, $alias );
2657 // Is there a JOIN clause for this table?
2658 if ( isset( $join_conds[$alias] ) ) {
2659 list( $joinType, $conds ) = $join_conds[$alias];
2660 $tableClause = $joinType;
2661 $tableClause .= ' ' . $joinedTable;
2662 if ( isset( $use_index[$alias] ) ) { // has USE INDEX?
2663 $use = $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) );
2665 $tableClause .= ' ' . $use;
2668 if ( isset( $ignore_index[$alias] ) ) { // has IGNORE INDEX?
2669 $ignore = $this->ignoreIndexClause(
2670 implode( ',', (array)$ignore_index[$alias] ) );
2671 if ( $ignore != '' ) {
2672 $tableClause .= ' ' . $ignore;
2675 $on = $this->makeList( (array)$conds, self
::LIST_AND
);
2677 $tableClause .= ' ON (' . $on . ')';
2680 $retJOIN[] = $tableClause;
2681 } elseif ( isset( $use_index[$alias] ) ) {
2682 // Is there an INDEX clause for this table?
2683 $tableClause = $joinedTable;
2684 $tableClause .= ' ' . $this->useIndexClause(
2685 implode( ',', (array)$use_index[$alias] )
2688 $ret[] = $tableClause;
2689 } elseif ( isset( $ignore_index[$alias] ) ) {
2690 // Is there an INDEX clause for this table?
2691 $tableClause = $joinedTable;
2692 $tableClause .= ' ' . $this->ignoreIndexClause(
2693 implode( ',', (array)$ignore_index[$alias] )
2696 $ret[] = $tableClause;
2698 $tableClause = $joinedTable;
2700 $ret[] = $tableClause;
2704 // We can't separate explicit JOIN clauses with ',', use ' ' for those
2705 $implicitJoins = $ret ?
implode( ',', $ret ) : "";
2706 $explicitJoins = $retJOIN ?
implode( ' ', $retJOIN ) : "";
2708 // Compile our final table clause
2709 return implode( ' ', [ $implicitJoins, $explicitJoins ] );
2713 * Allows for index remapping in queries where this is not consistent across DBMS
2715 * @param string $index
2718 protected function indexName( $index ) {
2719 return $this->indexAliases
[$index] ??
$index;
2722 public function addQuotes( $s ) {
2723 if ( $s instanceof Blob
) {
2726 if ( $s === null ) {
2728 } elseif ( is_bool( $s ) ) {
2731 # This will also quote numeric values. This should be harmless,
2732 # and protects against weird problems that occur when they really
2733 # _are_ strings such as article titles and string->number->string
2734 # conversion is not 1:1.
2735 return "'" . $this->strencode( $s ) . "'";
2739 public function addIdentifierQuotes( $s ) {
2740 return '"' . str_replace( '"', '""', $s ) . '"';
2744 * Returns if the given identifier looks quoted or not according to
2745 * the database convention for quoting identifiers .
2747 * @note Do not use this to determine if untrusted input is safe.
2748 * A malicious user can trick this function.
2749 * @param string $name
2752 public function isQuotedIdentifier( $name ) {
2753 return $name[0] == '"' && substr( $name, -1, 1 ) == '"';
2758 * @param string $escapeChar
2761 protected function escapeLikeInternal( $s, $escapeChar = '`' ) {
2762 return str_replace( [ $escapeChar, '%', '_' ],
2763 [ "{$escapeChar}{$escapeChar}", "{$escapeChar}%", "{$escapeChar}_" ],
2767 public function buildLike() {
2768 $params = func_get_args();
2770 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
2771 $params = $params[0];
2776 // We use ` instead of \ as the default LIKE escape character, since addQuotes()
2777 // may escape backslashes, creating problems of double escaping. The `
2778 // character has good cross-DBMS compatibility, avoiding special operators
2779 // in MS SQL like ^ and %
2782 foreach ( $params as $value ) {
2783 if ( $value instanceof LikeMatch
) {
2784 $s .= $value->toString();
2786 $s .= $this->escapeLikeInternal( $value, $escapeChar );
2791 $this->addQuotes( $s ) . ' ESCAPE ' . $this->addQuotes( $escapeChar ) . ' ';
2794 public function anyChar() {
2795 return new LikeMatch( '_' );
2798 public function anyString() {
2799 return new LikeMatch( '%' );
2802 public function nextSequenceValue( $seqName ) {
2807 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
2808 * is only needed because a) MySQL must be as efficient as possible due to
2809 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2810 * which index to pick. Anyway, other databases might have different
2811 * indexes on a given table. So don't bother overriding this unless you're
2813 * @param string $index
2816 public function useIndexClause( $index ) {
2821 * IGNORE INDEX clause. Unlikely to be useful for anything but MySQL. This
2822 * is only needed because a) MySQL must be as efficient as possible due to
2823 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2824 * which index to pick. Anyway, other databases might have different
2825 * indexes on a given table. So don't bother overriding this unless you're
2827 * @param string $index
2830 public function ignoreIndexClause( $index ) {
2834 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__
) {
2835 if ( count( $rows ) == 0 ) {
2839 $uniqueIndexes = (array)$uniqueIndexes;
2841 if ( !is_array( reset( $rows ) ) ) {
2846 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2847 $affectedRowCount = 0;
2848 foreach ( $rows as $row ) {
2849 // Delete rows which collide with this one
2850 $indexWhereClauses = [];
2851 foreach ( $uniqueIndexes as $index ) {
2852 $indexColumns = (array)$index;
2853 $indexRowValues = array_intersect_key( $row, array_flip( $indexColumns ) );
2854 if ( count( $indexRowValues ) != count( $indexColumns ) ) {
2855 throw new DBUnexpectedError(
2857 'New record does not provide all values for unique key (' .
2858 implode( ', ', $indexColumns ) . ')'
2860 } elseif ( in_array( null, $indexRowValues, true ) ) {
2861 throw new DBUnexpectedError(
2863 'New record has a null value for unique key (' .
2864 implode( ', ', $indexColumns ) . ')'
2867 $indexWhereClauses[] = $this->makeList( $indexRowValues, LIST_AND
);
2870 if ( $indexWhereClauses ) {
2871 $this->delete( $table, $this->makeList( $indexWhereClauses, LIST_OR
), $fname );
2872 $affectedRowCount +
= $this->affectedRows();
2875 // Now insert the row
2876 $this->insert( $table, $row, $fname );
2877 $affectedRowCount +
= $this->affectedRows();
2879 $this->endAtomic( $fname );
2880 $this->affectedRowCount
= $affectedRowCount;
2881 } catch ( Exception
$e ) {
2882 $this->cancelAtomic( $fname );
2888 * REPLACE query wrapper for MySQL and SQLite, which have a native REPLACE
2891 * @param string $table Table name
2892 * @param array|string $rows Row(s) to insert
2893 * @param string $fname Caller function name
2895 protected function nativeReplace( $table, $rows, $fname ) {
2896 $table = $this->tableName( $table );
2899 if ( !is_array( reset( $rows ) ) ) {
2903 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES ';
2906 foreach ( $rows as $row ) {
2913 $sql .= '(' . $this->makeList( $row ) . ')';
2916 $this->query( $sql, $fname );
2919 public function upsert( $table, array $rows, $uniqueIndexes, array $set,
2922 if ( $rows === [] ) {
2923 return true; // nothing to do
2926 $uniqueIndexes = (array)$uniqueIndexes;
2927 if ( !is_array( reset( $rows ) ) ) {
2931 if ( count( $uniqueIndexes ) ) {
2932 $clauses = []; // list WHERE clauses that each identify a single row
2933 foreach ( $rows as $row ) {
2934 foreach ( $uniqueIndexes as $index ) {
2935 $index = is_array( $index ) ?
$index : [ $index ]; // columns
2936 $rowKey = []; // unique key to this row
2937 foreach ( $index as $column ) {
2938 $rowKey[$column] = $row[$column];
2940 $clauses[] = $this->makeList( $rowKey, self
::LIST_AND
);
2943 $where = [ $this->makeList( $clauses, self
::LIST_OR
) ];
2948 $affectedRowCount = 0;
2950 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2951 # Update any existing conflicting row(s)
2952 if ( $where !== false ) {
2953 $this->update( $table, $set, $where, $fname );
2954 $affectedRowCount +
= $this->affectedRows();
2956 # Now insert any non-conflicting row(s)
2957 $this->insert( $table, $rows, $fname, [ 'IGNORE' ] );
2958 $affectedRowCount +
= $this->affectedRows();
2959 $this->endAtomic( $fname );
2960 $this->affectedRowCount
= $affectedRowCount;
2961 } catch ( Exception
$e ) {
2962 $this->cancelAtomic( $fname );
2969 public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
2973 throw new DBUnexpectedError( $this, __METHOD__
. ' called with empty $conds' );
2976 $delTable = $this->tableName( $delTable );
2977 $joinTable = $this->tableName( $joinTable );
2978 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
2979 if ( $conds != '*' ) {
2980 $sql .= 'WHERE ' . $this->makeList( $conds, self
::LIST_AND
);
2984 $this->query( $sql, $fname );
2987 public function textFieldSize( $table, $field ) {
2988 $table = $this->tableName( $table );
2989 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
2990 $res = $this->query( $sql, __METHOD__
);
2991 $row = $this->fetchObject( $res );
2995 if ( preg_match( '/\((.*)\)/', $row->Type
, $m ) ) {
3004 public function delete( $table, $conds, $fname = __METHOD__
) {
3006 throw new DBUnexpectedError( $this, __METHOD__
. ' called with no conditions' );
3009 $table = $this->tableName( $table );
3010 $sql = "DELETE FROM $table";
3012 if ( $conds != '*' ) {
3013 if ( is_array( $conds ) ) {
3014 $conds = $this->makeList( $conds, self
::LIST_AND
);
3016 $sql .= ' WHERE ' . $conds;
3019 $this->query( $sql, $fname );
3024 final public function insertSelect(
3025 $destTable, $srcTable, $varMap, $conds,
3026 $fname = __METHOD__
, $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3028 static $hints = [ 'NO_AUTO_COLUMNS' ];
3030 $insertOptions = (array)$insertOptions;
3031 $selectOptions = (array)$selectOptions;
3033 if ( $this->cliMode
&& $this->isInsertSelectSafe( $insertOptions, $selectOptions ) ) {
3034 // For massive migrations with downtime, we don't want to select everything
3035 // into memory and OOM, so do all this native on the server side if possible.
3036 $this->nativeInsertSelect(
3042 array_diff( $insertOptions, $hints ),
3047 $this->nonNativeInsertSelect(
3053 array_diff( $insertOptions, $hints ),
3063 * @param array $insertOptions INSERT options
3064 * @param array $selectOptions SELECT options
3065 * @return bool Whether an INSERT SELECT with these options will be replication safe
3068 protected function isInsertSelectSafe( array $insertOptions, array $selectOptions ) {
3073 * Implementation of insertSelect() based on select() and insert()
3075 * @see IDatabase::insertSelect()
3077 * @param string $destTable
3078 * @param string|array $srcTable
3079 * @param array $varMap
3080 * @param array $conds
3081 * @param string $fname
3082 * @param array $insertOptions
3083 * @param array $selectOptions
3084 * @param array $selectJoinConds
3086 protected function nonNativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3087 $fname = __METHOD__
,
3088 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3090 // For web requests, do a locking SELECT and then INSERT. This puts the SELECT burden
3091 // on only the master (without needing row-based-replication). It also makes it easy to
3092 // know how big the INSERT is going to be.
3094 foreach ( $varMap as $dstColumn => $sourceColumnOrSql ) {
3095 $fields[] = $this->fieldNameWithAlias( $sourceColumnOrSql, $dstColumn );
3097 $selectOptions[] = 'FOR UPDATE';
3098 $res = $this->select(
3099 $srcTable, implode( ',', $fields ), $conds, $fname, $selectOptions, $selectJoinConds
3106 $affectedRowCount = 0;
3107 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
3110 foreach ( $res as $row ) {
3111 $rows[] = (array)$row;
3113 // Avoid inserts that are too huge
3114 if ( count( $rows ) >= $this->nonNativeInsertSelectBatchSize
) {
3115 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
3119 $affectedRowCount +
= $this->affectedRows();
3123 if ( $rows && $ok ) {
3124 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
3126 $affectedRowCount +
= $this->affectedRows();
3130 $this->endAtomic( $fname );
3131 $this->affectedRowCount
= $affectedRowCount;
3133 $this->cancelAtomic( $fname );
3135 } catch ( Exception
$e ) {
3136 $this->cancelAtomic( $fname );
3142 * Native server-side implementation of insertSelect() for situations where
3143 * we don't want to select everything into memory
3145 * @see IDatabase::insertSelect()
3146 * @param string $destTable
3147 * @param string|array $srcTable
3148 * @param array $varMap
3149 * @param array $conds
3150 * @param string $fname
3151 * @param array $insertOptions
3152 * @param array $selectOptions
3153 * @param array $selectJoinConds
3155 protected function nativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3156 $fname = __METHOD__
,
3157 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3159 $destTable = $this->tableName( $destTable );
3161 if ( !is_array( $insertOptions ) ) {
3162 $insertOptions = [ $insertOptions ];
3165 $insertOptions = $this->makeInsertOptions( $insertOptions );
3167 $selectSql = $this->selectSQLText(
3169 array_values( $varMap ),
3176 $sql = "INSERT $insertOptions" .
3177 " INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ') ' .
3180 $this->query( $sql, $fname );
3184 * Construct a LIMIT query with optional offset. This is used for query
3185 * pages. The SQL should be adjusted so that only the first $limit rows
3186 * are returned. If $offset is provided as well, then the first $offset
3187 * rows should be discarded, and the next $limit rows should be returned.
3188 * If the result of the query is not ordered, then the rows to be returned
3189 * are theoretically arbitrary.
3191 * $sql is expected to be a SELECT, if that makes a difference.
3193 * The version provided by default works in MySQL and SQLite. It will very
3194 * likely need to be overridden for most other DBMSes.
3196 * @param string $sql SQL query we will append the limit too
3197 * @param int $limit The SQL limit
3198 * @param int|bool $offset The SQL offset (default false)
3199 * @throws DBUnexpectedError
3202 public function limitResult( $sql, $limit, $offset = false ) {
3203 if ( !is_numeric( $limit ) ) {
3204 throw new DBUnexpectedError( $this,
3205 "Invalid non-numeric limit passed to limitResult()\n" );
3208 return "$sql LIMIT "
3209 . ( ( is_numeric( $offset ) && $offset != 0 ) ?
"{$offset}," : "" )
3213 public function unionSupportsOrderAndLimit() {
3214 return true; // True for almost every DB supported
3217 public function unionQueries( $sqls, $all ) {
3218 $glue = $all ?
') UNION ALL (' : ') UNION (';
3220 return '(' . implode( $glue, $sqls ) . ')';
3223 public function unionConditionPermutations(
3224 $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__
,
3225 $options = [], $join_conds = []
3227 // First, build the Cartesian product of $permute_conds
3229 foreach ( $permute_conds as $field => $values ) {
3231 // Skip empty $values
3234 $values = array_unique( $values ); // For sanity
3236 foreach ( $conds as $cond ) {
3237 foreach ( $values as $value ) {
3238 $cond[$field] = $value;
3239 $newConds[] = $cond; // Arrays are by-value, not by-reference, so this works
3245 $extra_conds = $extra_conds === '' ?
[] : (array)$extra_conds;
3247 // If there's just one condition and no subordering, hand off to
3248 // selectSQLText directly.
3249 if ( count( $conds ) === 1 &&
3250 ( !isset( $options['INNER ORDER BY'] ) ||
!$this->unionSupportsOrderAndLimit() )
3252 return $this->selectSQLText(
3253 $table, $vars, $conds[0] +
$extra_conds, $fname, $options, $join_conds
3257 // Otherwise, we need to pull out the order and limit to apply after
3258 // the union. Then build the SQL queries for each set of conditions in
3259 // $conds. Then union them together (using UNION ALL, because the
3260 // product *should* already be distinct).
3261 $orderBy = $this->makeOrderBy( $options );
3262 $limit = $options['LIMIT'] ??
null;
3263 $offset = $options['OFFSET'] ??
false;
3264 $all = empty( $options['NOTALL'] ) && !in_array( 'NOTALL', $options );
3265 if ( !$this->unionSupportsOrderAndLimit() ) {
3266 unset( $options['ORDER BY'], $options['LIMIT'], $options['OFFSET'] );
3268 if ( array_key_exists( 'INNER ORDER BY', $options ) ) {
3269 $options['ORDER BY'] = $options['INNER ORDER BY'];
3271 if ( $limit !== null && is_numeric( $offset ) && $offset != 0 ) {
3272 // We need to increase the limit by the offset rather than
3273 // using the offset directly, otherwise it'll skip incorrectly
3274 // in the subqueries.
3275 $options['LIMIT'] = $limit +
$offset;
3276 unset( $options['OFFSET'] );
3281 foreach ( $conds as $cond ) {
3282 $sqls[] = $this->selectSQLText(
3283 $table, $vars, $cond +
$extra_conds, $fname, $options, $join_conds
3286 $sql = $this->unionQueries( $sqls, $all ) . $orderBy;
3287 if ( $limit !== null ) {
3288 $sql = $this->limitResult( $sql, $limit, $offset );
3294 public function conditional( $cond, $trueVal, $falseVal ) {
3295 if ( is_array( $cond ) ) {
3296 $cond = $this->makeList( $cond, self
::LIST_AND
);
3299 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
3302 public function strreplace( $orig, $old, $new ) {
3303 return "REPLACE({$orig}, {$old}, {$new})";
3306 public function getServerUptime() {
3310 public function wasDeadlock() {
3314 public function wasLockTimeout() {
3318 public function wasConnectionLoss() {
3319 return $this->wasConnectionError( $this->lastErrno() );
3322 public function wasReadOnlyError() {
3326 public function wasErrorReissuable() {
3328 $this->wasDeadlock() ||
3329 $this->wasLockTimeout() ||
3330 $this->wasConnectionLoss()
3335 * Do not use this method outside of Database/DBError classes
3337 * @param int|string $errno
3338 * @return bool Whether the given query error was a connection drop
3340 public function wasConnectionError( $errno ) {
3345 * @return bool Whether it is known that the last query error only caused statement rollback
3346 * @note This is for backwards compatibility for callers catching DBError exceptions in
3347 * order to ignore problems like duplicate key errors or foriegn key violations
3350 protected function wasKnownStatementRollbackError() {
3351 return false; // don't know; it could have caused a transaction rollback
3354 public function deadlockLoop() {
3355 $args = func_get_args();
3356 $function = array_shift( $args );
3357 $tries = self
::DEADLOCK_TRIES
;
3359 $this->begin( __METHOD__
);
3362 /** @var Exception $e */
3366 $retVal = $function( ...$args );
3368 } catch ( DBQueryError
$e ) {
3369 if ( $this->wasDeadlock() ) {
3370 // Retry after a randomized delay
3371 usleep( mt_rand( self
::DEADLOCK_DELAY_MIN
, self
::DEADLOCK_DELAY_MAX
) );
3373 // Throw the error back up
3377 } while ( --$tries > 0 );
3379 if ( $tries <= 0 ) {
3380 // Too many deadlocks; give up
3381 $this->rollback( __METHOD__
);
3384 $this->commit( __METHOD__
);
3390 public function masterPosWait( DBMasterPos
$pos, $timeout ) {
3391 # Real waits are implemented in the subclass.
3395 public function getReplicaPos() {
3400 public function getMasterPos() {
3405 public function serverIsReadOnly() {
3409 final public function onTransactionResolution( callable
$callback, $fname = __METHOD__
) {
3410 if ( !$this->trxLevel
) {
3411 throw new DBUnexpectedError( $this, "No transaction is active." );
3413 $this->trxEndCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3416 final public function onTransactionCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3417 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3418 // Start an implicit transaction similar to how query() does
3419 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3420 $this->trxAutomatic
= true;
3423 $this->trxIdleCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3424 if ( !$this->trxLevel
) {
3425 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_IDLE
);
3429 final public function onTransactionIdle( callable
$callback, $fname = __METHOD__
) {
3430 $this->onTransactionCommitOrIdle( $callback, $fname );
3433 final public function onTransactionPreCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3434 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3435 // Start an implicit transaction similar to how query() does
3436 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3437 $this->trxAutomatic
= true;
3440 if ( $this->trxLevel
) {
3441 $this->trxPreCommitCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3443 // No transaction is active nor will start implicitly, so make one for this callback
3444 $this->startAtomic( __METHOD__
, self
::ATOMIC_CANCELABLE
);
3447 $this->endAtomic( __METHOD__
);
3448 } catch ( Exception
$e ) {
3449 $this->cancelAtomic( __METHOD__
);
3456 * @return AtomicSectionIdentifier|null ID of the topmost atomic section level
3458 private function currentAtomicSectionId() {
3459 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3460 $levelInfo = end( $this->trxAtomicLevels
);
3462 return $levelInfo[1];
3469 * @param AtomicSectionIdentifier $old
3470 * @param AtomicSectionIdentifier $new
3472 private function reassignCallbacksForSection(
3473 AtomicSectionIdentifier
$old, AtomicSectionIdentifier
$new
3475 foreach ( $this->trxPreCommitCallbacks
as $key => $info ) {
3476 if ( $info[2] === $old ) {
3477 $this->trxPreCommitCallbacks
[$key][2] = $new;
3480 foreach ( $this->trxIdleCallbacks
as $key => $info ) {
3481 if ( $info[2] === $old ) {
3482 $this->trxIdleCallbacks
[$key][2] = $new;
3485 foreach ( $this->trxEndCallbacks
as $key => $info ) {
3486 if ( $info[2] === $old ) {
3487 $this->trxEndCallbacks
[$key][2] = $new;
3493 * @param AtomicSectionIdentifier[] $sectionIds ID of an actual savepoint
3494 * @throws UnexpectedValueException
3496 private function modifyCallbacksForCancel( array $sectionIds ) {
3497 // Cancel the "on commit" callbacks owned by this savepoint
3498 $this->trxIdleCallbacks
= array_filter(
3499 $this->trxIdleCallbacks
,
3500 function ( $entry ) use ( $sectionIds ) {
3501 return !in_array( $entry[2], $sectionIds, true );
3504 $this->trxPreCommitCallbacks
= array_filter(
3505 $this->trxPreCommitCallbacks
,
3506 function ( $entry ) use ( $sectionIds ) {
3507 return !in_array( $entry[2], $sectionIds, true );
3510 // Make "on resolution" callbacks owned by this savepoint to perceive a rollback
3511 foreach ( $this->trxEndCallbacks
as $key => $entry ) {
3512 if ( in_array( $entry[2], $sectionIds, true ) ) {
3513 $callback = $entry[0];
3514 $this->trxEndCallbacks
[$key][0] = function () use ( $callback ) {
3515 return $callback( self
::TRIGGER_ROLLBACK
, $this );
3521 final public function setTransactionListener( $name, callable
$callback = null ) {
3523 $this->trxRecurringCallbacks
[$name] = $callback;
3525 unset( $this->trxRecurringCallbacks
[$name] );
3530 * Whether to disable running of post-COMMIT/ROLLBACK callbacks
3532 * This method should not be used outside of Database/LoadBalancer
3534 * @param bool $suppress
3537 final public function setTrxEndCallbackSuppression( $suppress ) {
3538 $this->trxEndCallbacksSuppressed
= $suppress;
3542 * Actually consume and run any "on transaction idle/resolution" callbacks.
3544 * This method should not be used outside of Database/LoadBalancer
3546 * @param int $trigger IDatabase::TRIGGER_* constant
3547 * @return int Number of callbacks attempted
3551 public function runOnTransactionIdleCallbacks( $trigger ) {
3552 if ( $this->trxLevel
) { // sanity
3553 throw new DBUnexpectedError( $this, __METHOD__
. ': a transaction is still open.' );
3556 if ( $this->trxEndCallbacksSuppressed
) {
3561 $autoTrx = $this->getFlag( self
::DBO_TRX
); // automatic begin() enabled?
3562 /** @var Exception $e */
3563 $e = null; // first exception
3564 do { // callbacks may add callbacks :)
3565 $callbacks = array_merge(
3566 $this->trxIdleCallbacks
,
3567 $this->trxEndCallbacks
// include "transaction resolution" callbacks
3569 $this->trxIdleCallbacks
= []; // consumed (and recursion guard)
3570 $this->trxEndCallbacks
= []; // consumed (recursion guard)
3571 foreach ( $callbacks as $callback ) {
3573 list( $phpCallback ) = $callback;
3574 $this->clearFlag( self
::DBO_TRX
); // make each query its own transaction
3576 call_user_func( $phpCallback, $trigger, $this );
3577 } catch ( Exception
$ex ) {
3578 call_user_func( $this->errorLogger
, $ex );
3580 // Some callbacks may use startAtomic/endAtomic, so make sure
3581 // their transactions are ended so other callbacks don't fail
3582 if ( $this->trxLevel() ) {
3583 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
3587 $this->setFlag( self
::DBO_TRX
); // restore automatic begin()
3589 $this->clearFlag( self
::DBO_TRX
); // restore auto-commit
3593 } while ( count( $this->trxIdleCallbacks
) );
3595 if ( $e instanceof Exception
) {
3596 throw $e; // re-throw any first exception
3603 * Actually consume and run any "on transaction pre-commit" callbacks.
3605 * This method should not be used outside of Database/LoadBalancer
3608 * @return int Number of callbacks attempted
3611 public function runOnTransactionPreCommitCallbacks() {
3614 $e = null; // first exception
3615 do { // callbacks may add callbacks :)
3616 $callbacks = $this->trxPreCommitCallbacks
;
3617 $this->trxPreCommitCallbacks
= []; // consumed (and recursion guard)
3618 foreach ( $callbacks as $callback ) {
3621 list( $phpCallback ) = $callback;
3622 $phpCallback( $this );
3623 } catch ( Exception
$ex ) {
3624 ( $this->errorLogger
)( $ex );
3628 } while ( count( $this->trxPreCommitCallbacks
) );
3630 if ( $e instanceof Exception
) {
3631 throw $e; // re-throw any first exception
3638 * Actually run any "transaction listener" callbacks.
3640 * This method should not be used outside of Database/LoadBalancer
3642 * @param int $trigger IDatabase::TRIGGER_* constant
3646 public function runTransactionListenerCallbacks( $trigger ) {
3647 if ( $this->trxEndCallbacksSuppressed
) {
3651 /** @var Exception $e */
3652 $e = null; // first exception
3654 foreach ( $this->trxRecurringCallbacks
as $phpCallback ) {
3656 $phpCallback( $trigger, $this );
3657 } catch ( Exception
$ex ) {
3658 ( $this->errorLogger
)( $ex );
3663 if ( $e instanceof Exception
) {
3664 throw $e; // re-throw any first exception
3669 * Create a savepoint
3671 * This is used internally to implement atomic sections. It should not be
3675 * @param string $identifier Identifier for the savepoint
3676 * @param string $fname Calling function name
3678 protected function doSavepoint( $identifier, $fname ) {
3679 $this->query( 'SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3683 * Release a savepoint
3685 * This is used internally to implement atomic sections. It should not be
3689 * @param string $identifier Identifier for the savepoint
3690 * @param string $fname Calling function name
3692 protected function doReleaseSavepoint( $identifier, $fname ) {
3693 $this->query( 'RELEASE SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3697 * Rollback to a savepoint
3699 * This is used internally to implement atomic sections. It should not be
3703 * @param string $identifier Identifier for the savepoint
3704 * @param string $fname Calling function name
3706 protected function doRollbackToSavepoint( $identifier, $fname ) {
3707 $this->query( 'ROLLBACK TO SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3711 * @param string $fname
3714 private function nextSavepointId( $fname ) {
3715 $savepointId = self
::$SAVEPOINT_PREFIX . ++
$this->trxAtomicCounter
;
3716 if ( strlen( $savepointId ) > 30 ) {
3717 // 30 == Oracle's identifier length limit (pre 12c)
3718 // With a 22 character prefix, that puts the highest number at 99999999.
3719 throw new DBUnexpectedError(
3721 'There have been an excessively large number of atomic sections in a transaction'
3722 . " started by $this->trxFname (at $fname)"
3726 return $savepointId;
3729 final public function startAtomic(
3730 $fname = __METHOD__
, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3732 $savepointId = $cancelable === self
::ATOMIC_CANCELABLE ? self
::$NOT_APPLICABLE : null;
3734 if ( !$this->trxLevel
) {
3735 $this->begin( $fname, self
::TRANSACTION_INTERNAL
); // sets trxAutomatic
3736 // If DBO_TRX is set, a series of startAtomic/endAtomic pairs will result
3737 // in all changes being in one transaction to keep requests transactional.
3738 if ( $this->getFlag( self
::DBO_TRX
) ) {
3739 // Since writes could happen in between the topmost atomic sections as part
3740 // of the transaction, those sections will need savepoints.
3741 $savepointId = $this->nextSavepointId( $fname );
3742 $this->doSavepoint( $savepointId, $fname );
3744 $this->trxAutomaticAtomic
= true;
3746 } elseif ( $cancelable === self
::ATOMIC_CANCELABLE
) {
3747 $savepointId = $this->nextSavepointId( $fname );
3748 $this->doSavepoint( $savepointId, $fname );
3751 $sectionId = new AtomicSectionIdentifier
;
3752 $this->trxAtomicLevels
[] = [ $fname, $sectionId, $savepointId ];
3753 $this->queryLogger
->debug( 'startAtomic: entering level ' .
3754 ( count( $this->trxAtomicLevels
) - 1 ) . " ($fname)" );
3759 final public function endAtomic( $fname = __METHOD__
) {
3760 if ( !$this->trxLevel ||
!$this->trxAtomicLevels
) {
3761 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)." );
3764 // Check if the current section matches $fname
3765 $pos = count( $this->trxAtomicLevels
) - 1;
3766 list( $savedFname, $sectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3767 $this->queryLogger
->debug( "endAtomic: leaving level $pos ($fname)" );
3769 if ( $savedFname !== $fname ) {
3770 throw new DBUnexpectedError(
3772 "Invalid atomic section ended (got $fname but expected $savedFname)."
3776 // Remove the last section (no need to re-index the array)
3777 array_pop( $this->trxAtomicLevels
);
3779 if ( !$this->trxAtomicLevels
&& $this->trxAutomaticAtomic
) {
3780 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3781 } elseif ( $savepointId !== null && $savepointId !== self
::$NOT_APPLICABLE ) {
3782 $this->doReleaseSavepoint( $savepointId, $fname );
3785 // Hoist callback ownership for callbacks in the section that just ended;
3786 // all callbacks should have an owner that is present in trxAtomicLevels.
3787 $currentSectionId = $this->currentAtomicSectionId();
3788 if ( $currentSectionId ) {
3789 $this->reassignCallbacksForSection( $sectionId, $currentSectionId );
3793 final public function cancelAtomic(
3794 $fname = __METHOD__
, AtomicSectionIdentifier
$sectionId = null
3796 if ( !$this->trxLevel ||
!$this->trxAtomicLevels
) {
3797 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)." );
3800 $excisedFnames = [];
3801 if ( $sectionId !== null ) {
3802 // Find the (last) section with the given $sectionId
3804 foreach ( $this->trxAtomicLevels
as $i => list( $asFname, $asId, $spId ) ) {
3805 if ( $asId === $sectionId ) {
3810 throw new DBUnexpectedError( $this, "Atomic section not found (for $fname)" );
3812 // Remove all descendant sections and re-index the array
3814 $len = count( $this->trxAtomicLevels
);
3815 for ( $i = $pos +
1; $i < $len; ++
$i ) {
3816 $excisedFnames[] = $this->trxAtomicLevels
[$i][0];
3817 $excisedIds[] = $this->trxAtomicLevels
[$i][1];
3819 $this->trxAtomicLevels
= array_slice( $this->trxAtomicLevels
, 0, $pos +
1 );
3820 $this->modifyCallbacksForCancel( $excisedIds );
3823 // Check if the current section matches $fname
3824 $pos = count( $this->trxAtomicLevels
) - 1;
3825 list( $savedFname, $savedSectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3827 if ( $excisedFnames ) {
3828 $this->queryLogger
->debug( "cancelAtomic: canceling level $pos ($savedFname) " .
3829 "and descendants " . implode( ', ', $excisedFnames ) );
3831 $this->queryLogger
->debug( "cancelAtomic: canceling level $pos ($savedFname)" );
3834 if ( $savedFname !== $fname ) {
3835 throw new DBUnexpectedError(
3837 "Invalid atomic section ended (got $fname but expected $savedFname)."
3841 // Remove the last section (no need to re-index the array)
3842 array_pop( $this->trxAtomicLevels
);
3843 $this->modifyCallbacksForCancel( [ $savedSectionId ] );
3845 if ( $savepointId !== null ) {
3846 // Rollback the transaction to the state just before this atomic section
3847 if ( $savepointId === self
::$NOT_APPLICABLE ) {
3848 $this->rollback( $fname, self
::FLUSHING_INTERNAL
);
3850 $this->doRollbackToSavepoint( $savepointId, $fname );
3851 $this->trxStatus
= self
::STATUS_TRX_OK
; // no exception; recovered
3852 $this->trxStatusIgnoredCause
= null;
3854 } elseif ( $this->trxStatus
> self
::STATUS_TRX_ERROR
) {
3855 // Put the transaction into an error state if it's not already in one
3856 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
3857 $this->trxStatusCause
= new DBUnexpectedError(
3859 "Uncancelable atomic section canceled (got $fname)."
3863 $this->affectedRowCount
= 0; // for the sake of consistency
3866 final public function doAtomicSection(
3867 $fname, callable
$callback, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3869 $sectionId = $this->startAtomic( $fname, $cancelable );
3871 $res = $callback( $this, $fname );
3872 } catch ( Exception
$e ) {
3873 $this->cancelAtomic( $fname, $sectionId );
3877 $this->endAtomic( $fname );
3882 final public function begin( $fname = __METHOD__
, $mode = self
::TRANSACTION_EXPLICIT
) {
3883 static $modes = [ self
::TRANSACTION_EXPLICIT
, self
::TRANSACTION_INTERNAL
];
3884 if ( !in_array( $mode, $modes, true ) ) {
3885 throw new DBUnexpectedError( $this, "$fname: invalid mode parameter '$mode'." );
3888 // Protect against mismatched atomic section, transaction nesting, and snapshot loss
3889 if ( $this->trxLevel
) {
3890 if ( $this->trxAtomicLevels
) {
3891 $levels = $this->flatAtomicSectionList();
3892 $msg = "$fname: Got explicit BEGIN while atomic section(s) $levels are open.";
3893 throw new DBUnexpectedError( $this, $msg );
3894 } elseif ( !$this->trxAutomatic
) {
3895 $msg = "$fname: Explicit transaction already active (from {$this->trxFname}).";
3896 throw new DBUnexpectedError( $this, $msg );
3898 $msg = "$fname: Implicit transaction already active (from {$this->trxFname}).";
3899 throw new DBUnexpectedError( $this, $msg );
3901 } elseif ( $this->getFlag( self
::DBO_TRX
) && $mode !== self
::TRANSACTION_INTERNAL
) {
3902 $msg = "$fname: Implicit transaction expected (DBO_TRX set).";
3903 throw new DBUnexpectedError( $this, $msg );
3906 $this->assertHasConnectionHandle();
3908 $this->doBegin( $fname );
3909 $this->trxStatus
= self
::STATUS_TRX_OK
;
3910 $this->trxStatusIgnoredCause
= null;
3911 $this->trxAtomicCounter
= 0;
3912 $this->trxTimestamp
= microtime( true );
3913 $this->trxFname
= $fname;
3914 $this->trxDoneWrites
= false;
3915 $this->trxAutomaticAtomic
= false;
3916 $this->trxAtomicLevels
= [];
3917 $this->trxShortId
= sprintf( '%06x', mt_rand( 0, 0xffffff ) );
3918 $this->trxWriteDuration
= 0.0;
3919 $this->trxWriteQueryCount
= 0;
3920 $this->trxWriteAffectedRows
= 0;
3921 $this->trxWriteAdjDuration
= 0.0;
3922 $this->trxWriteAdjQueryCount
= 0;
3923 $this->trxWriteCallers
= [];
3924 // First SELECT after BEGIN will establish the snapshot in REPEATABLE-READ.
3925 // Get an estimate of the replication lag before any such queries.
3926 $this->trxReplicaLag
= null; // clear cached value first
3927 $this->trxReplicaLag
= $this->getApproximateLagStatus()['lag'];
3928 // T147697: make explicitTrxActive() return true until begin() finishes. This way, no
3929 // caller will think its OK to muck around with the transaction just because startAtomic()
3930 // has not yet completed (e.g. setting trxAtomicLevels).
3931 $this->trxAutomatic
= ( $mode === self
::TRANSACTION_INTERNAL
);
3935 * Issues the BEGIN command to the database server.
3937 * @see Database::begin()
3938 * @param string $fname
3940 protected function doBegin( $fname ) {
3941 $this->query( 'BEGIN', $fname );
3942 $this->trxLevel
= 1;
3945 final public function commit( $fname = __METHOD__
, $flush = self
::FLUSHING_ONE
) {
3946 static $modes = [ self
::FLUSHING_ONE
, self
::FLUSHING_ALL_PEERS
, self
::FLUSHING_INTERNAL
];
3947 if ( !in_array( $flush, $modes, true ) ) {
3948 throw new DBUnexpectedError( $this, "$fname: invalid flush parameter '$flush'." );
3951 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3952 // There are still atomic sections open; this cannot be ignored
3953 $levels = $this->flatAtomicSectionList();
3954 throw new DBUnexpectedError(
3956 "$fname: Got COMMIT while atomic sections $levels are still open."
3960 if ( $flush === self
::FLUSHING_INTERNAL ||
$flush === self
::FLUSHING_ALL_PEERS
) {
3961 if ( !$this->trxLevel
) {
3962 return; // nothing to do
3963 } elseif ( !$this->trxAutomatic
) {
3964 throw new DBUnexpectedError(
3966 "$fname: Flushing an explicit transaction, getting out of sync."
3970 if ( !$this->trxLevel
) {
3971 $this->queryLogger
->error(
3972 "$fname: No transaction to commit, something got out of sync." );
3973 return; // nothing to do
3974 } elseif ( $this->trxAutomatic
) {
3975 throw new DBUnexpectedError(
3977 "$fname: Expected mass commit of all peer transactions (DBO_TRX set)."
3982 $this->assertHasConnectionHandle();
3984 $this->runOnTransactionPreCommitCallbacks();
3986 $writeTime = $this->pendingWriteQueryDuration( self
::ESTIMATE_DB_APPLY
);
3987 $this->doCommit( $fname );
3988 $this->trxStatus
= self
::STATUS_TRX_NONE
;
3990 if ( $this->trxDoneWrites
) {
3991 $this->lastWriteTime
= microtime( true );
3992 $this->trxProfiler
->transactionWritingOut(
3994 $this->getDomainID(),
3997 $this->trxWriteAffectedRows
4001 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
4002 if ( $flush !== self
::FLUSHING_ALL_PEERS
) {
4003 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_COMMIT
);
4004 $this->runTransactionListenerCallbacks( self
::TRIGGER_COMMIT
);
4009 * Issues the COMMIT command to the database server.
4011 * @see Database::commit()
4012 * @param string $fname
4014 protected function doCommit( $fname ) {
4015 if ( $this->trxLevel
) {
4016 $this->query( 'COMMIT', $fname );
4017 $this->trxLevel
= 0;
4021 final public function rollback( $fname = __METHOD__
, $flush = '' ) {
4022 $trxActive = $this->trxLevel
;
4024 if ( $flush !== self
::FLUSHING_INTERNAL
&& $flush !== self
::FLUSHING_ALL_PEERS
) {
4025 if ( $this->getFlag( self
::DBO_TRX
) ) {
4026 throw new DBUnexpectedError(
4028 "$fname: Expected mass rollback of all peer transactions (DBO_TRX set)."
4034 $this->assertHasConnectionHandle();
4036 $this->doRollback( $fname );
4037 $this->trxStatus
= self
::STATUS_TRX_NONE
;
4038 $this->trxAtomicLevels
= [];
4039 // Estimate the RTT via a query now that trxStatus is OK
4040 $writeTime = $this->pingAndCalculateLastTrxApplyTime();
4042 if ( $this->trxDoneWrites
) {
4043 $this->trxProfiler
->transactionWritingOut(
4045 $this->getDomainID(),
4048 $this->trxWriteAffectedRows
4053 // Clear any commit-dependant callbacks. They might even be present
4054 // only due to transaction rounds, with no SQL transaction being active
4055 $this->trxIdleCallbacks
= [];
4056 $this->trxPreCommitCallbacks
= [];
4058 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
4059 if ( $trxActive && $flush !== self
::FLUSHING_ALL_PEERS
) {
4061 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
4062 } catch ( Exception
$e ) {
4063 // already logged; finish and let LoadBalancer move on during mass-rollback
4066 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
4067 } catch ( Exception
$e ) {
4068 // already logged; let LoadBalancer move on during mass-rollback
4071 $this->affectedRowCount
= 0; // for the sake of consistency
4076 * Issues the ROLLBACK command to the database server.
4078 * @see Database::rollback()
4079 * @param string $fname
4081 protected function doRollback( $fname ) {
4082 if ( $this->trxLevel
) {
4083 # Disconnects cause rollback anyway, so ignore those errors
4084 $ignoreErrors = true;
4085 $this->query( 'ROLLBACK', $fname, $ignoreErrors );
4086 $this->trxLevel
= 0;
4090 public function flushSnapshot( $fname = __METHOD__
) {
4091 if ( $this->writesOrCallbacksPending() ||
$this->explicitTrxActive() ) {
4092 // This only flushes transactions to clear snapshots, not to write data
4093 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4094 throw new DBUnexpectedError(
4096 "$fname: Cannot flush snapshot because writes are pending ($fnames)."
4100 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4103 public function explicitTrxActive() {
4104 return $this->trxLevel
&& ( $this->trxAtomicLevels ||
!$this->trxAutomatic
);
4107 public function duplicateTableStructure(
4108 $oldName, $newName, $temporary = false, $fname = __METHOD__
4110 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4113 public function listTables( $prefix = null, $fname = __METHOD__
) {
4114 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4117 public function listViews( $prefix = null, $fname = __METHOD__
) {
4118 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4121 public function timestamp( $ts = 0 ) {
4122 $t = new ConvertibleTimestamp( $ts );
4123 // Let errors bubble up to avoid putting garbage in the DB
4124 return $t->getTimestamp( TS_MW
);
4127 public function timestampOrNull( $ts = null ) {
4128 if ( is_null( $ts ) ) {
4131 return $this->timestamp( $ts );
4135 public function affectedRows() {
4136 return ( $this->affectedRowCount
=== null )
4137 ?
$this->fetchAffectedRowCount() // default to driver value
4138 : $this->affectedRowCount
;
4142 * @return int Number of retrieved rows according to the driver
4144 abstract protected function fetchAffectedRowCount();
4147 * Take the result from a query, and wrap it in a ResultWrapper if
4148 * necessary. Boolean values are passed through as is, to indicate success
4149 * of write queries or failure.
4151 * Once upon a time, Database::query() returned a bare MySQL result
4152 * resource, and it was necessary to call this function to convert it to
4153 * a wrapper. Nowadays, raw database objects are never exposed to external
4154 * callers, so this is unnecessary in external code.
4156 * @param bool|ResultWrapper|resource $result
4157 * @return bool|ResultWrapper
4159 protected function resultObject( $result ) {
4162 } elseif ( $result instanceof ResultWrapper
) {
4164 } elseif ( $result === true ) {
4165 // Successful write query
4168 return new ResultWrapper( $this, $result );
4172 public function ping( &$rtt = null ) {
4173 // Avoid hitting the server if it was hit recently
4174 if ( $this->isOpen() && ( microtime( true ) - $this->lastPing
) < self
::PING_TTL
) {
4175 if ( !func_num_args() ||
$this->rttEstimate
> 0 ) {
4176 $rtt = $this->rttEstimate
;
4177 return true; // don't care about $rtt
4181 // This will reconnect if possible or return false if not
4182 $this->clearFlag( self
::DBO_TRX
, self
::REMEMBER_PRIOR
);
4183 $ok = ( $this->query( self
::PING_QUERY
, __METHOD__
, true ) !== false );
4184 $this->restoreFlags( self
::RESTORE_PRIOR
);
4187 $rtt = $this->rttEstimate
;
4194 * Close any existing (dead) database connection and open a new connection
4196 * @param string $fname
4197 * @return bool True if new connection is opened successfully, false if error
4199 protected function replaceLostConnection( $fname ) {
4200 $this->closeConnection();
4201 $this->opened
= false;
4202 $this->conn
= false;
4204 $this->handleSessionLossPreconnect();
4213 $this->tablePrefix()
4215 $this->lastPing
= microtime( true );
4218 $this->connLogger
->warning(
4219 $fname . ': lost connection to {dbserver}; reconnected',
4221 'dbserver' => $this->getServer(),
4222 'trace' => ( new RuntimeException() )->getTraceAsString()
4225 } catch ( DBConnectionError
$e ) {
4228 $this->connLogger
->error(
4229 $fname . ': lost connection to {dbserver} permanently',
4230 [ 'dbserver' => $this->getServer() ]
4234 $this->handleSessionLossPostconnect();
4239 public function getSessionLagStatus() {
4240 return $this->getRecordedTransactionLagStatus() ?
: $this->getApproximateLagStatus();
4244 * Get the replica DB lag when the current transaction started
4246 * This is useful when transactions might use snapshot isolation
4247 * (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data
4248 * is this lag plus transaction duration. If they don't, it is still
4249 * safe to be pessimistic. This returns null if there is no transaction.
4251 * This returns null if the lag status for this transaction was not yet recorded.
4253 * @return array|null ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)
4256 final protected function getRecordedTransactionLagStatus() {
4257 return ( $this->trxLevel
&& $this->trxReplicaLag
!== null )
4258 ?
[ 'lag' => $this->trxReplicaLag
, 'since' => $this->trxTimestamp() ]
4263 * Get a replica DB lag estimate for this server
4265 * @return array ('lag': seconds or false on error, 'since': UNIX timestamp of estimate)
4268 protected function getApproximateLagStatus() {
4270 'lag' => $this->getLBInfo( 'replica' ) ?
$this->getLag() : 0,
4271 'since' => microtime( true )
4276 * Merge the result of getSessionLagStatus() for several DBs
4277 * using the most pessimistic values to estimate the lag of
4278 * any data derived from them in combination
4280 * This is information is useful for caching modules
4282 * @see WANObjectCache::set()
4283 * @see WANObjectCache::getWithSetCallback()
4285 * @param IDatabase $db1
4286 * @param IDatabase|null $db2 [optional]
4287 * @return array Map of values:
4288 * - lag: highest lag of any of the DBs or false on error (e.g. replication stopped)
4289 * - since: oldest UNIX timestamp of any of the DB lag estimates
4290 * - pending: whether any of the DBs have uncommitted changes
4294 public static function getCacheSetOptions( IDatabase
$db1, IDatabase
$db2 = null ) {
4295 $res = [ 'lag' => 0, 'since' => INF
, 'pending' => false ];
4296 foreach ( func_get_args() as $db ) {
4297 /** @var IDatabase $db */
4298 $status = $db->getSessionLagStatus();
4299 if ( $status['lag'] === false ) {
4300 $res['lag'] = false;
4301 } elseif ( $res['lag'] !== false ) {
4302 $res['lag'] = max( $res['lag'], $status['lag'] );
4304 $res['since'] = min( $res['since'], $status['since'] );
4305 $res['pending'] = $res['pending'] ?
: $db->writesPending();
4311 public function getLag() {
4315 public function maxListLen() {
4319 public function encodeBlob( $b ) {
4323 public function decodeBlob( $b ) {
4324 if ( $b instanceof Blob
) {
4330 public function setSessionOptions( array $options ) {
4333 public function sourceFile(
4335 callable
$lineCallback = null,
4336 callable
$resultCallback = null,
4338 callable
$inputCallback = null
4340 Wikimedia\
suppressWarnings();
4341 $fp = fopen( $filename, 'r' );
4342 Wikimedia\restoreWarnings
();
4344 if ( $fp === false ) {
4345 throw new RuntimeException( "Could not open \"{$filename}\".\n" );
4349 $fname = __METHOD__
. "( $filename )";
4353 $error = $this->sourceStream(
4354 $fp, $lineCallback, $resultCallback, $fname, $inputCallback );
4355 } catch ( Exception
$e ) {
4365 public function setSchemaVars( $vars ) {
4366 $this->schemaVars
= $vars;
4369 public function sourceStream(
4371 callable
$lineCallback = null,
4372 callable
$resultCallback = null,
4373 $fname = __METHOD__
,
4374 callable
$inputCallback = null
4376 $delimiterReset = new ScopedCallback(
4377 function ( $delimiter ) {
4378 $this->delimiter
= $delimiter;
4380 [ $this->delimiter
]
4384 while ( !feof( $fp ) ) {
4385 if ( $lineCallback ) {
4386 call_user_func( $lineCallback );
4389 $line = trim( fgets( $fp ) );
4391 if ( $line == '' ) {
4395 if ( $line[0] == '-' && $line[1] == '-' ) {
4403 $done = $this->streamStatementEnd( $cmd, $line );
4407 if ( $done ||
feof( $fp ) ) {
4408 $cmd = $this->replaceVars( $cmd );
4410 if ( $inputCallback ) {
4411 $callbackResult = $inputCallback( $cmd );
4413 if ( is_string( $callbackResult ) ||
!$callbackResult ) {
4414 $cmd = $callbackResult;
4419 $res = $this->query( $cmd, $fname );
4421 if ( $resultCallback ) {
4422 $resultCallback( $res, $this );
4425 if ( $res === false ) {
4426 $err = $this->lastError();
4428 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
4435 ScopedCallback
::consume( $delimiterReset );
4440 * Called by sourceStream() to check if we've reached a statement end
4442 * @param string &$sql SQL assembled so far
4443 * @param string &$newLine New line about to be added to $sql
4444 * @return bool Whether $newLine contains end of the statement
4446 public function streamStatementEnd( &$sql, &$newLine ) {
4447 if ( $this->delimiter
) {
4449 $newLine = preg_replace(
4450 '/' . preg_quote( $this->delimiter
, '/' ) . '$/', '', $newLine );
4451 if ( $newLine != $prev ) {
4460 * Database independent variable replacement. Replaces a set of variables
4461 * in an SQL statement with their contents as given by $this->getSchemaVars().
4463 * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables.
4465 * - '{$var}' should be used for text and is passed through the database's
4467 * - `{$var}` should be used for identifiers (e.g. table and database names).
4468 * It is passed through the database's addIdentifierQuotes method which
4469 * can be overridden if the database uses something other than backticks.
4470 * - / *_* / or / *$wgDBprefix* / passes the name that follows through the
4471 * database's tableName method.
4472 * - / *i* / passes the name that follows through the database's indexName method.
4473 * - In all other cases, / *$var* / is left unencoded. Except for table options,
4474 * its use should be avoided. In 1.24 and older, string encoding was applied.
4476 * @param string $ins SQL statement to replace variables in
4477 * @return string The new SQL statement with variables replaced
4479 protected function replaceVars( $ins ) {
4480 $vars = $this->getSchemaVars();
4481 return preg_replace_callback(
4483 /\* (\$wgDBprefix|[_i]) \*/ (\w*) | # 1-2. tableName, indexName
4484 \'\{\$ (\w+) }\' | # 3. addQuotes
4485 `\{\$ (\w+) }` | # 4. addIdentifierQuotes
4486 /\*\$ (\w+) \*/ # 5. leave unencoded
4488 function ( $m ) use ( $vars ) {
4489 // Note: Because of <https://bugs.php.net/bug.php?id=51881>,
4490 // check for both nonexistent keys *and* the empty string.
4491 if ( isset( $m[1] ) && $m[1] !== '' ) {
4492 if ( $m[1] === 'i' ) {
4493 return $this->indexName( $m[2] );
4495 return $this->tableName( $m[2] );
4497 } elseif ( isset( $m[3] ) && $m[3] !== '' && array_key_exists( $m[3], $vars ) ) {
4498 return $this->addQuotes( $vars[$m[3]] );
4499 } elseif ( isset( $m[4] ) && $m[4] !== '' && array_key_exists( $m[4], $vars ) ) {
4500 return $this->addIdentifierQuotes( $vars[$m[4]] );
4501 } elseif ( isset( $m[5] ) && $m[5] !== '' && array_key_exists( $m[5], $vars ) ) {
4502 return $vars[$m[5]];
4512 * Get schema variables. If none have been set via setSchemaVars(), then
4513 * use some defaults from the current object.
4517 protected function getSchemaVars() {
4518 if ( $this->schemaVars
) {
4519 return $this->schemaVars
;
4521 return $this->getDefaultSchemaVars();
4526 * Get schema variables to use if none have been set via setSchemaVars().
4528 * Override this in derived classes to provide variables for tables.sql
4529 * and SQL patch files.
4533 protected function getDefaultSchemaVars() {
4537 public function lockIsFree( $lockName, $method ) {
4538 // RDBMs methods for checking named locks may or may not count this thread itself.
4539 // In MySQL, IS_FREE_LOCK() returns 0 if the thread already has the lock. This is
4540 // the behavior choosen by the interface for this method.
4541 return !isset( $this->namedLocksHeld
[$lockName] );
4544 public function lock( $lockName, $method, $timeout = 5 ) {
4545 $this->namedLocksHeld
[$lockName] = 1;
4550 public function unlock( $lockName, $method ) {
4551 unset( $this->namedLocksHeld
[$lockName] );
4556 public function getScopedLockAndFlush( $lockKey, $fname, $timeout ) {
4557 if ( $this->writesOrCallbacksPending() ) {
4558 // This only flushes transactions to clear snapshots, not to write data
4559 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4560 throw new DBUnexpectedError(
4562 "$fname: Cannot flush pre-lock snapshot because writes are pending ($fnames)."
4566 if ( !$this->lock( $lockKey, $fname, $timeout ) ) {
4570 $unlocker = new ScopedCallback( function () use ( $lockKey, $fname ) {
4571 if ( $this->trxLevel() ) {
4572 // There is a good chance an exception was thrown, causing any early return
4573 // from the caller. Let any error handler get a chance to issue rollback().
4574 // If there isn't one, let the error bubble up and trigger server-side rollback.
4575 $this->onTransactionResolution(
4576 function () use ( $lockKey, $fname ) {
4577 $this->unlock( $lockKey, $fname );
4582 $this->unlock( $lockKey, $fname );
4586 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4591 public function namedLocksEnqueue() {
4595 public function tableLocksHaveTransactionScope() {
4599 final public function lockTables( array $read, array $write, $method ) {
4600 if ( $this->writesOrCallbacksPending() ) {
4601 throw new DBUnexpectedError( $this, "Transaction writes or callbacks still pending." );
4604 if ( $this->tableLocksHaveTransactionScope() ) {
4605 $this->startAtomic( $method );
4608 return $this->doLockTables( $read, $write, $method );
4612 * Helper function for lockTables() that handles the actual table locking
4614 * @param array $read Array of tables to lock for read access
4615 * @param array $write Array of tables to lock for write access
4616 * @param string $method Name of caller
4619 protected function doLockTables( array $read, array $write, $method ) {
4623 final public function unlockTables( $method ) {
4624 if ( $this->tableLocksHaveTransactionScope() ) {
4625 $this->endAtomic( $method );
4627 return true; // locks released on COMMIT/ROLLBACK
4630 return $this->doUnlockTables( $method );
4634 * Helper function for unlockTables() that handles the actual table unlocking
4636 * @param string $method Name of caller
4639 protected function doUnlockTables( $method ) {
4645 * @param string $tableName
4646 * @param string $fName
4647 * @return bool|ResultWrapper
4650 public function dropTable( $tableName, $fName = __METHOD__
) {
4651 if ( !$this->tableExists( $tableName, $fName ) ) {
4654 $sql = "DROP TABLE " . $this->tableName( $tableName ) . " CASCADE";
4656 return $this->query( $sql, $fName );
4659 public function getInfinity() {
4663 public function encodeExpiry( $expiry ) {
4664 return ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() )
4665 ?
$this->getInfinity()
4666 : $this->timestamp( $expiry );
4669 public function decodeExpiry( $expiry, $format = TS_MW
) {
4670 if ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() ) {
4674 return ConvertibleTimestamp
::convert( $format, $expiry );
4677 public function setBigSelects( $value = true ) {
4681 public function isReadOnly() {
4682 return ( $this->getReadOnlyReason() !== false );
4686 * @return string|bool Reason this DB is read-only or false if it is not
4688 protected function getReadOnlyReason() {
4689 $reason = $this->getLBInfo( 'readOnlyReason' );
4691 return is_string( $reason ) ?
$reason : false;
4694 public function setTableAliases( array $aliases ) {
4695 $this->tableAliases
= $aliases;
4698 public function setIndexAliases( array $aliases ) {
4699 $this->indexAliases
= $aliases;
4707 protected function hasFlags( $field, $flags ) {
4708 return ( ( $field & $flags ) === $flags );
4712 * Get the underlying binding connection handle
4714 * Makes sure the connection resource is set (disconnects and ping() failure can unset it).
4715 * This catches broken callers than catch and ignore disconnection exceptions.
4716 * Unlike checking isOpen(), this is safe to call inside of open().
4719 * @throws DBUnexpectedError
4722 protected function getBindingHandle() {
4723 if ( !$this->conn
) {
4724 throw new DBUnexpectedError(
4726 'DB connection was already closed or the connection dropped.'
4737 public function __toString() {
4738 return (string)$this->conn
;
4742 * Make sure that copies do not share the same client binding handle
4743 * @throws DBConnectionError
4745 public function __clone() {
4746 $this->connLogger
->warning(
4747 "Cloning " . static::class . " is not recommended; forking connection:\n" .
4748 ( new RuntimeException() )->getTraceAsString()
4751 if ( $this->isOpen() ) {
4752 // Open a new connection resource without messing with the old one
4753 $this->opened
= false;
4754 $this->conn
= false;
4755 $this->trxEndCallbacks
= []; // don't copy
4756 $this->handleSessionLossPreconnect(); // no trx or locks anymore
4763 $this->tablePrefix()
4765 $this->lastPing
= microtime( true );
4770 * Called by serialize. Throw an exception when DB connection is serialized.
4771 * This causes problems on some database engines because the connection is
4772 * not restored on unserialize.
4774 public function __sleep() {
4775 throw new RuntimeException( 'Database serialization may cause problems, since ' .
4776 'the connection is not restored on wakeup.' );
4780 * Run a few simple sanity checks and close dangling connections
4782 public function __destruct() {
4783 if ( $this->trxLevel
&& $this->trxDoneWrites
) {
4784 trigger_error( "Uncommitted DB writes (transaction from {$this->trxFname})." );
4787 $danglingWriters = $this->pendingWriteAndCallbackCallers();
4788 if ( $danglingWriters ) {
4789 $fnames = implode( ', ', $danglingWriters );
4790 trigger_error( "DB transaction writes or callbacks still pending ($fnames)." );
4793 if ( $this->conn
) {
4794 // Avoid connection leaks for sanity. Normally, resources close at script completion.
4795 // The connection might already be closed in zend/hhvm by now, so suppress warnings.
4796 Wikimedia\
suppressWarnings();
4797 $this->closeConnection();
4798 Wikimedia\restoreWarnings
();
4799 $this->conn
= false;
4800 $this->opened
= false;
4806 * @deprecated since 1.28
4808 class_alias( Database
::class, 'DatabaseBase' );
4811 * @deprecated since 1.29
4813 class_alias( Database
::class, 'Database' );