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 Lock granularity is on the level of the entire database */
65 const ATTR_DB_LEVEL_LOCKING
= 'db-level-locking';
66 /** @var string The SCHEMA keyword refers to a grouping of tables in a database */
67 const ATTR_SCHEMAS_AS_TABLE_GROUPS
= 'supports-schemas';
69 /** @var int New Database instance will not be connected yet when returned */
70 const NEW_UNCONNECTED
= 0;
71 /** @var int New Database instance will already be connected when returned */
72 const NEW_CONNECTED
= 1;
74 /** @var string SQL query */
75 protected $lastQuery = '';
76 /** @var float|bool UNIX timestamp of last write query */
77 protected $lastWriteTime = false;
78 /** @var string|bool */
79 protected $phpError = false;
80 /** @var string Server that this instance is currently connected to */
82 /** @var string User that this instance is currently connected under the name of */
84 /** @var string Password used to establish the current connection */
86 /** @var array[] Map of (table => (dbname, schema, prefix) map) */
87 protected $tableAliases = [];
88 /** @var string[] Map of (index alias => index) */
89 protected $indexAliases = [];
90 /** @var bool Whether this PHP instance is for a CLI script */
92 /** @var string Agent name for query profiling */
94 /** @var array Parameters used by initConnection() to establish a connection */
95 protected $connectionParams = [];
96 /** @var BagOStuff APC cache */
98 /** @var LoggerInterface */
99 protected $connLogger;
100 /** @var LoggerInterface */
101 protected $queryLogger;
102 /** @var callable Error logging callback */
103 protected $errorLogger;
104 /** @var callable Deprecation logging callback */
105 protected $deprecationLogger;
107 /** @var resource|null Database connection */
108 protected $conn = null;
110 protected $opened = false;
112 /** @var array[] List of (callable, method name, atomic section id) */
113 protected $trxIdleCallbacks = [];
114 /** @var array[] List of (callable, method name, atomic section id) */
115 protected $trxPreCommitCallbacks = [];
116 /** @var array[] List of (callable, method name, atomic section id) */
117 protected $trxEndCallbacks = [];
118 /** @var callable[] Map of (name => callable) */
119 protected $trxRecurringCallbacks = [];
120 /** @var bool Whether to suppress triggering of transaction end callbacks */
121 protected $trxEndCallbacksSuppressed = false;
126 protected $lbInfo = [];
127 /** @var array|bool */
128 protected $schemaVars = false;
130 protected $sessionVars = [];
131 /** @var array|null */
132 protected $preparedArgs;
133 /** @var string|bool|null Stashed value of html_errors INI setting */
134 protected $htmlErrors;
136 protected $delimiter = ';';
137 /** @var DatabaseDomain */
138 protected $currentDomain;
139 /** @var integer|null Rows affected by the last query to query() or its CRUD wrappers */
140 protected $affectedRowCount;
143 * @var int Transaction status
145 protected $trxStatus = self
::STATUS_TRX_NONE
;
147 * @var Exception|null The last error that caused the status to become STATUS_TRX_ERROR
149 protected $trxStatusCause;
151 * @var array|null If wasKnownStatementRollbackError() prevented trxStatus from being set,
152 * the relevant details are stored here.
154 protected $trxStatusIgnoredCause;
156 * Either 1 if a transaction is active or 0 otherwise.
157 * The other Trx fields may not be meaningfull if this is 0.
161 protected $trxLevel = 0;
163 * Either a short hexidecimal string if a transaction is active or ""
166 * @see Database::trxLevel
168 protected $trxShortId = '';
170 * The UNIX time that the transaction started. Callers can assume that if
171 * snapshot isolation is used, then the data is *at least* up to date to that
172 * point (possibly more up-to-date since the first SELECT defines the snapshot).
175 * @see Database::trxLevel
177 private $trxTimestamp = null;
178 /** @var float Lag estimate at the time of BEGIN */
179 private $trxReplicaLag = null;
181 * Remembers the function name given for starting the most recent transaction via begin().
182 * Used to provide additional context for error reporting.
185 * @see Database::trxLevel
187 private $trxFname = null;
189 * Record if possible write queries were done in the last transaction started
192 * @see Database::trxLevel
194 private $trxDoneWrites = false;
196 * Record if the current transaction was started implicitly due to DBO_TRX being set.
199 * @see Database::trxLevel
201 private $trxAutomatic = false;
203 * Counter for atomic savepoint identifiers. Reset when a new transaction begins.
207 private $trxAtomicCounter = 0;
209 * Array of levels of atomicity within transactions
211 * @var array List of (name, unique ID, savepoint ID)
213 private $trxAtomicLevels = [];
215 * Record if the current transaction was started implicitly by Database::startAtomic
219 private $trxAutomaticAtomic = false;
221 * Track the write query callers of the current transaction
225 private $trxWriteCallers = [];
227 * @var float Seconds spent in write queries for the current transaction
229 private $trxWriteDuration = 0.0;
231 * @var int Number of write queries for the current transaction
233 private $trxWriteQueryCount = 0;
235 * @var int Number of rows affected by write queries for the current transaction
237 private $trxWriteAffectedRows = 0;
239 * @var float Like trxWriteQueryCount but excludes lock-bound, easy to replicate, queries
241 private $trxWriteAdjDuration = 0.0;
243 * @var int Number of write queries counted in trxWriteAdjDuration
245 private $trxWriteAdjQueryCount = 0;
247 * @var float RTT time estimate
249 private $rttEstimate = 0.0;
251 /** @var array Map of (name => 1) for locks obtained via lock() */
252 private $namedLocksHeld = [];
253 /** @var array Map of (table name => 1) for TEMPORARY tables */
254 protected $sessionTempTables = [];
256 /** @var IDatabase|null Lazy handle to the master DB this server replicates from */
257 private $lazyMasterHandle;
259 /** @var float UNIX timestamp */
260 protected $lastPing = 0.0;
262 /** @var int[] Prior flags member variable values */
263 private $priorFlags = [];
265 /** @var callable|null */
267 /** @var TransactionProfiler */
268 protected $trxProfiler;
271 protected $nonNativeInsertSelectBatchSize = 10000;
273 /** @var string Idiom used when a cancelable atomic section started the transaction */
274 private static $NOT_APPLICABLE = 'n/a';
275 /** @var string Prefix to the atomic section counter used to make savepoint IDs */
276 private static $SAVEPOINT_PREFIX = 'wikimedia_rdbms_atomic';
278 /** @var int Transaction is in a error state requiring a full or savepoint rollback */
279 const STATUS_TRX_ERROR
= 1;
280 /** @var int Transaction is active and in a normal state */
281 const STATUS_TRX_OK
= 2;
282 /** @var int No transaction is active */
283 const STATUS_TRX_NONE
= 3;
286 * @note exceptions for missing libraries/drivers should be thrown in initConnection()
287 * @param array $params Parameters passed from Database::factory()
289 protected function __construct( array $params ) {
290 foreach ( [ 'host', 'user', 'password', 'dbname', 'schema', 'tablePrefix' ] as $name ) {
291 $this->connectionParams
[$name] = $params[$name];
294 $this->cliMode
= $params['cliMode'];
295 // Agent name is added to SQL queries in a comment, so make sure it can't break out
296 $this->agent
= str_replace( '/', '-', $params['agent'] );
298 $this->flags
= $params['flags'];
299 if ( $this->flags
& self
::DBO_DEFAULT
) {
300 if ( $this->cliMode
) {
301 $this->flags
&= ~self
::DBO_TRX
;
303 $this->flags |
= self
::DBO_TRX
;
306 // Disregard deprecated DBO_IGNORE flag (T189999)
307 $this->flags
&= ~self
::DBO_IGNORE
;
309 $this->sessionVars
= $params['variables'];
311 $this->srvCache
= $params['srvCache'] ??
new HashBagOStuff();
313 $this->profiler
= is_callable( $params['profiler'] ) ?
$params['profiler'] : null;
314 $this->trxProfiler
= $params['trxProfiler'];
315 $this->connLogger
= $params['connLogger'];
316 $this->queryLogger
= $params['queryLogger'];
317 $this->errorLogger
= $params['errorLogger'];
318 $this->deprecationLogger
= $params['deprecationLogger'];
320 if ( isset( $params['nonNativeInsertSelectBatchSize'] ) ) {
321 $this->nonNativeInsertSelectBatchSize
= $params['nonNativeInsertSelectBatchSize'];
324 // Set initial dummy domain until open() sets the final DB/prefix
325 $this->currentDomain
= new DatabaseDomain(
326 $params['dbname'] != '' ?
$params['dbname'] : null,
327 $params['schema'] != '' ?
$params['schema'] : null,
328 $params['tablePrefix']
333 * Initialize the connection to the database over the wire (or to local files)
335 * @throws LogicException
336 * @throws InvalidArgumentException
337 * @throws DBConnectionError
340 final public function initConnection() {
341 if ( $this->isOpen() ) {
342 throw new LogicException( __METHOD__
. ': already connected.' );
344 // Establish the connection
345 $this->doInitConnection();
349 * Actually connect to the database over the wire (or to local files)
351 * @throws InvalidArgumentException
352 * @throws DBConnectionError
355 protected function doInitConnection() {
356 if ( strlen( $this->connectionParams
['user'] ) ) {
358 $this->connectionParams
['host'],
359 $this->connectionParams
['user'],
360 $this->connectionParams
['password'],
361 $this->connectionParams
['dbname'],
362 $this->connectionParams
['schema'],
363 $this->connectionParams
['tablePrefix']
366 throw new InvalidArgumentException( "No database user provided." );
371 * Open a new connection to the database (closing any existing one)
373 * @param string $server Database server host
374 * @param string $user Database user name
375 * @param string $password Database user password
376 * @param string $dbName Database name
377 * @param string|null $schema Database schema name
378 * @param string $tablePrefix Table prefix
380 * @throws DBConnectionError
382 abstract protected function open( $server, $user, $password, $dbName, $schema, $tablePrefix );
385 * Construct a Database subclass instance given a database type and parameters
387 * This also connects to the database immediately upon object construction
389 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
390 * @param array $p Parameter map with keys:
391 * - host : The hostname of the DB server
392 * - user : The name of the database user the client operates under
393 * - password : The password for the database user
394 * - dbname : The name of the database to use where queries do not specify one.
395 * The database must exist or an error might be thrown. Setting this to the empty string
396 * will avoid any such errors and make the handle have no implicit database scope. This is
397 * useful for queries like SHOW STATUS, CREATE DATABASE, or DROP DATABASE. Note that a
398 * "database" in Postgres is rougly equivalent to an entire MySQL server. This the domain
399 * in which user names and such are defined, e.g. users are database-specific in Postgres.
400 * - schema : The database schema to use (if supported). A "schema" in Postgres is roughly
401 * equivalent to a "database" in MySQL. Note that MySQL and SQLite do not use schemas.
402 * - tablePrefix : Optional table prefix that is implicitly added on to all table names
403 * recognized in queries. This can be used in place of schemas for handle site farms.
404 * - flags : Optional bitfield of DBO_* constants that define connection, protocol,
405 * buffering, and transaction behavior. It is STRONGLY adviced to leave the DBO_DEFAULT
406 * flag in place UNLESS this this database simply acts as a key/value store.
407 * - driver: Optional name of a specific DB client driver. For MySQL, there is only the
408 * 'mysqli' driver; the old one 'mysql' has been removed.
409 * - variables: Optional map of session variables to set after connecting. This can be
410 * used to adjust lock timeouts or encoding modes and the like.
411 * - connLogger: Optional PSR-3 logger interface instance.
412 * - queryLogger: Optional PSR-3 logger interface instance.
413 * - profiler : Optional callback that takes a section name argument and returns
414 * a ScopedCallback instance that ends the profile section in its destructor.
415 * These will be called in query(), using a simplified version of the SQL that
416 * also includes the agent as a SQL comment.
417 * - trxProfiler: Optional TransactionProfiler instance.
418 * - errorLogger: Optional callback that takes an Exception and logs it.
419 * - deprecationLogger: Optional callback that takes a string and logs it.
420 * - cliMode: Whether to consider the execution context that of a CLI script.
421 * - agent: Optional name used to identify the end-user in query profiling/logging.
422 * - srvCache: Optional BagOStuff instance to an APC-style cache.
423 * - nonNativeInsertSelectBatchSize: Optional batch size for non-native INSERT SELECT emulation.
424 * @param int $connect One of the class constants (NEW_CONNECTED, NEW_UNCONNECTED) [optional]
425 * @return Database|null If the database driver or extension cannot be found
426 * @throws InvalidArgumentException If the database driver or extension cannot be found
429 final public static function factory( $dbType, $p = [], $connect = self
::NEW_CONNECTED
) {
430 $class = self
::getClass( $dbType, $p['driver'] ??
null );
432 if ( class_exists( $class ) && is_subclass_of( $class, IDatabase
::class ) ) {
433 // Resolve some defaults for b/c
434 $p['host'] = $p['host'] ??
false;
435 $p['user'] = $p['user'] ??
false;
436 $p['password'] = $p['password'] ??
false;
437 $p['dbname'] = $p['dbname'] ??
false;
438 $p['flags'] = $p['flags'] ??
0;
439 $p['variables'] = $p['variables'] ??
[];
440 $p['tablePrefix'] = $p['tablePrefix'] ??
'';
441 $p['schema'] = $p['schema'] ??
null;
442 $p['cliMode'] = $p['cliMode'] ??
( PHP_SAPI
=== 'cli' || PHP_SAPI
=== 'phpdbg' );
443 $p['agent'] = $p['agent'] ??
'';
444 if ( !isset( $p['connLogger'] ) ) {
445 $p['connLogger'] = new NullLogger();
447 if ( !isset( $p['queryLogger'] ) ) {
448 $p['queryLogger'] = new NullLogger();
450 $p['profiler'] = $p['profiler'] ??
null;
451 if ( !isset( $p['trxProfiler'] ) ) {
452 $p['trxProfiler'] = new TransactionProfiler();
454 if ( !isset( $p['errorLogger'] ) ) {
455 $p['errorLogger'] = function ( Exception
$e ) {
456 trigger_error( get_class( $e ) . ': ' . $e->getMessage(), E_USER_WARNING
);
459 if ( !isset( $p['deprecationLogger'] ) ) {
460 $p['deprecationLogger'] = function ( $msg ) {
461 trigger_error( $msg, E_USER_DEPRECATED
);
465 /** @var Database $conn */
466 $conn = new $class( $p );
467 if ( $connect == self
::NEW_CONNECTED
) {
468 $conn->initConnection();
478 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
479 * @param string|null $driver Optional name of a specific DB client driver
480 * @return array Map of (Database::ATTR_* constant => value) for all such constants
481 * @throws InvalidArgumentException
484 final public static function attributesFromType( $dbType, $driver = null ) {
486 self
::ATTR_DB_LEVEL_LOCKING
=> false,
487 self
::ATTR_SCHEMAS_AS_TABLE_GROUPS
=> 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::ATTR_* 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 * @return bool Whether $sql is SQL for TEMPORARY table operation
1145 protected function registerTempTableOperation( $sql ) {
1147 '/^CREATE\s+TEMPORARY\s+TABLE\s+(?:IF\s+NOT\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1151 $this->sessionTempTables
[$matches[1]] = 1;
1154 } elseif ( preg_match(
1155 '/^DROP\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1159 $isTemp = isset( $this->sessionTempTables
[$matches[1]] );
1160 unset( $this->sessionTempTables
[$matches[1]] );
1163 } elseif ( preg_match(
1164 '/^TRUNCATE\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?[`"\']?(\w+)[`"\']?/i',
1168 return isset( $this->sessionTempTables
[$matches[1]] );
1169 } elseif ( preg_match(
1170 '/^(?:INSERT\s+(?:\w+\s+)?INTO|UPDATE|DELETE\s+FROM)\s+[`"\']?(\w+)[`"\']?/i',
1174 return isset( $this->sessionTempTables
[$matches[1]] );
1180 public function query( $sql, $fname = __METHOD__
, $tempIgnore = false ) {
1181 $this->assertTransactionStatus( $sql, $fname );
1182 $this->assertHasConnectionHandle();
1184 $priorTransaction = $this->trxLevel
;
1185 $priorWritesPending = $this->writesOrCallbacksPending();
1186 $this->lastQuery
= $sql;
1188 if ( $this->isWriteQuery( $sql ) ) {
1189 # In theory, non-persistent writes are allowed in read-only mode, but due to things
1190 # like https://bugs.mysql.com/bug.php?id=33669 that might not work anyway...
1191 $this->assertIsWritableMaster();
1192 # Avoid treating temporary table operations as meaningful "writes"
1193 $isEffectiveWrite = !$this->registerTempTableOperation( $sql );
1195 $isEffectiveWrite = false;
1198 # Add trace comment to the begin of the sql string, right after the operator.
1199 # Or, for one-word queries (like "BEGIN" or COMMIT") add it to the end (T44598)
1200 $commentedSql = preg_replace( '/\s|$/', " /* $fname {$this->agent} */ ", $sql, 1 );
1202 # Send the query to the server and fetch any corresponding errors
1203 $ret = $this->attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname );
1204 $lastError = $this->lastError();
1205 $lastErrno = $this->lastErrno();
1207 $recoverableSR = false; // recoverable statement rollback?
1208 $recoverableCL = false; // recoverable connection loss?
1210 if ( $ret === false && $this->wasConnectionLoss() ) {
1211 # Check if no meaningful session state was lost
1212 $recoverableCL = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
1213 # Update session state tracking and try to restore the connection
1214 $reconnected = $this->replaceLostConnection( __METHOD__
);
1215 # Silently resend the query to the server if it is safe and possible
1216 if ( $recoverableCL && $reconnected ) {
1217 $ret = $this->attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname );
1218 $lastError = $this->lastError();
1219 $lastErrno = $this->lastErrno();
1221 if ( $ret === false && $this->wasConnectionLoss() ) {
1222 # Query probably causes disconnects; reconnect and do not re-run it
1223 $this->replaceLostConnection( __METHOD__
);
1225 $recoverableCL = false; // connection does not need recovering
1226 $recoverableSR = $this->wasKnownStatementRollbackError();
1230 $recoverableSR = $this->wasKnownStatementRollbackError();
1233 if ( $ret === false ) {
1234 if ( $priorTransaction ) {
1235 if ( $recoverableSR ) {
1236 # We're ignoring an error that caused just the current query to be aborted.
1237 # But log the cause so we can log a deprecation notice if a caller actually
1239 $this->trxStatusIgnoredCause
= [ $lastError, $lastErrno, $fname ];
1240 } elseif ( !$recoverableCL ) {
1241 # Either the query was aborted or all queries after BEGIN where aborted.
1242 # In the first case, the only options going forward are (a) ROLLBACK, or
1243 # (b) ROLLBACK TO SAVEPOINT (if one was set). If the later case, the only
1244 # option is ROLLBACK, since the snapshots would have been released.
1245 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
1246 $this->trxStatusCause
=
1247 $this->getQueryExceptionAndLog( $lastError, $lastErrno, $sql, $fname );
1248 $tempIgnore = false; // cannot recover
1249 $this->trxStatusIgnoredCause
= null;
1253 $this->reportQueryError( $lastError, $lastErrno, $sql, $fname, $tempIgnore );
1256 return $this->resultObject( $ret );
1260 * Wrapper for query() that also handles profiling, logging, and affected row count updates
1262 * @param string $sql Original SQL query
1263 * @param string $commentedSql SQL query with debugging/trace comment
1264 * @param bool $isEffectiveWrite Whether the query is a (non-temporary table) write
1265 * @param string $fname Name of the calling function
1266 * @return bool|ResultWrapper True for a successful write query, ResultWrapper
1267 * object for a successful read query, or false on failure
1269 private function attemptQuery( $sql, $commentedSql, $isEffectiveWrite, $fname ) {
1270 $this->beginIfImplied( $sql, $fname );
1272 # Keep track of whether the transaction has write queries pending
1273 if ( $isEffectiveWrite ) {
1274 $this->lastWriteTime
= microtime( true );
1275 if ( $this->trxLevel
&& !$this->trxDoneWrites
) {
1276 $this->trxDoneWrites
= true;
1277 $this->trxProfiler
->transactionWritingIn(
1278 $this->server
, $this->getDomainID(), $this->trxShortId
);
1282 if ( $this->getFlag( self
::DBO_DEBUG
) ) {
1283 $this->queryLogger
->debug( "{$this->getDomainID()} {$commentedSql}" );
1286 $isMaster = !is_null( $this->getLBInfo( 'master' ) );
1287 # generalizeSQL() will probably cut down the query to reasonable
1288 # logging size most of the time. The substr is really just a sanity check.
1290 $queryProf = 'query-m: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1292 $queryProf = 'query: ' . substr( self
::generalizeSQL( $sql ), 0, 255 );
1295 # Include query transaction state
1296 $queryProf .= $this->trxShortId ?
" [TRX#{$this->trxShortId}]" : "";
1298 $startTime = microtime( true );
1299 $ps = $this->profiler ?
( $this->profiler
)( $queryProf ) : null;
1300 $this->affectedRowCount
= null;
1301 $ret = $this->doQuery( $commentedSql );
1302 $this->affectedRowCount
= $this->affectedRows();
1303 unset( $ps ); // profile out (if set)
1304 $queryRuntime = max( microtime( true ) - $startTime, 0.0 );
1306 if ( $ret !== false ) {
1307 $this->lastPing
= $startTime;
1308 if ( $isEffectiveWrite && $this->trxLevel
) {
1309 $this->updateTrxWriteQueryTime( $sql, $queryRuntime, $this->affectedRows() );
1310 $this->trxWriteCallers
[] = $fname;
1314 if ( $sql === self
::PING_QUERY
) {
1315 $this->rttEstimate
= $queryRuntime;
1318 $this->trxProfiler
->recordQueryCompletion(
1322 $isEffectiveWrite ?
$this->affectedRows() : $this->numRows( $ret )
1324 $this->queryLogger
->debug( $sql, [
1326 'master' => $isMaster,
1327 'runtime' => $queryRuntime,
1334 * Start an implicit transaction if DBO_TRX is enabled and no transaction is active
1336 * @param string $sql
1337 * @param string $fname
1339 private function beginIfImplied( $sql, $fname ) {
1342 $this->getFlag( self
::DBO_TRX
) &&
1343 $this->isTransactableQuery( $sql )
1345 $this->begin( __METHOD__
. " ($fname)", self
::TRANSACTION_INTERNAL
);
1346 $this->trxAutomatic
= true;
1351 * Update the estimated run-time of a query, not counting large row lock times
1353 * LoadBalancer can be set to rollback transactions that will create huge replication
1354 * lag. It bases this estimate off of pendingWriteQueryDuration(). Certain simple
1355 * queries, like inserting a row can take a long time due to row locking. This method
1356 * uses some simple heuristics to discount those cases.
1358 * @param string $sql A SQL write query
1359 * @param float $runtime Total runtime, including RTT
1360 * @param int $affected Affected row count
1362 private function updateTrxWriteQueryTime( $sql, $runtime, $affected ) {
1363 // Whether this is indicative of replica DB runtime (except for RBR or ws_repl)
1364 $indicativeOfReplicaRuntime = true;
1365 if ( $runtime > self
::SLOW_WRITE_SEC
) {
1366 $verb = $this->getQueryVerb( $sql );
1367 // insert(), upsert(), replace() are fast unless bulky in size or blocked on locks
1368 if ( $verb === 'INSERT' ) {
1369 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
;
1370 } elseif ( $verb === 'REPLACE' ) {
1371 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::SMALL_WRITE_ROWS
/ 2;
1375 $this->trxWriteDuration +
= $runtime;
1376 $this->trxWriteQueryCount +
= 1;
1377 $this->trxWriteAffectedRows +
= $affected;
1378 if ( $indicativeOfReplicaRuntime ) {
1379 $this->trxWriteAdjDuration +
= $runtime;
1380 $this->trxWriteAdjQueryCount +
= 1;
1385 * Error out if the DB is not in a valid state for a query via query()
1387 * @param string $sql
1388 * @param string $fname
1389 * @throws DBTransactionStateError
1391 private function assertTransactionStatus( $sql, $fname ) {
1392 $verb = $this->getQueryVerb( $sql );
1393 if ( $verb === 'USE' ) {
1394 throw new DBUnexpectedError( $this, "Got USE query; use selectDomain() instead." );
1397 if ( $verb === 'ROLLBACK' ) { // transaction/savepoint
1401 if ( $this->trxStatus
< self
::STATUS_TRX_OK
) {
1402 throw new DBTransactionStateError(
1404 "Cannot execute query from $fname while transaction status is ERROR.",
1406 $this->trxStatusCause
1408 } elseif ( $this->trxStatus
=== self
::STATUS_TRX_OK
&& $this->trxStatusIgnoredCause
) {
1409 list( $iLastError, $iLastErrno, $iFname ) = $this->trxStatusIgnoredCause
;
1410 call_user_func( $this->deprecationLogger
,
1411 "Caller from $fname ignored an error originally raised from $iFname: " .
1412 "[$iLastErrno] $iLastError"
1414 $this->trxStatusIgnoredCause
= null;
1418 public function assertNoOpenTransactions() {
1419 if ( $this->explicitTrxActive() ) {
1420 throw new DBTransactionError(
1422 "Explicit transaction still active. A caller may have caught an error. "
1423 . "Open transactions: " . $this->flatAtomicSectionList()
1429 * Determine whether it is safe to retry queries after a database connection is lost
1431 * @param string $sql SQL query
1432 * @param bool $priorWritesPending Whether there is a transaction open with
1433 * possible write queries or transaction pre-commit/idle callbacks
1434 * waiting on it to finish.
1435 * @return bool True if it is safe to retry the query, false otherwise
1437 private function canRecoverFromDisconnect( $sql, $priorWritesPending ) {
1438 # Transaction dropped; this can mean lost writes, or REPEATABLE-READ snapshots.
1439 # Dropped connections also mean that named locks are automatically released.
1440 # Only allow error suppression in autocommit mode or when the lost transaction
1441 # didn't matter anyway (aside from DBO_TRX snapshot loss).
1442 if ( $this->namedLocksHeld
) {
1443 return false; // possible critical section violation
1444 } elseif ( $this->sessionTempTables
) {
1445 return false; // tables might be queried latter
1446 } elseif ( $sql === 'COMMIT' ) {
1447 return !$priorWritesPending; // nothing written anyway? (T127428)
1448 } elseif ( $sql === 'ROLLBACK' ) {
1449 return true; // transaction lost...which is also what was requested :)
1450 } elseif ( $this->explicitTrxActive() ) {
1451 return false; // don't drop atomocity and explicit snapshots
1452 } elseif ( $priorWritesPending ) {
1453 return false; // prior writes lost from implicit transaction
1460 * Clean things up after session (and thus transaction) loss before reconnect
1462 private function handleSessionLossPreconnect() {
1463 // Clean up tracking of session-level things...
1464 // https://dev.mysql.com/doc/refman/5.7/en/implicit-commit.html
1465 // https://www.postgresql.org/docs/9.2/static/sql-createtable.html (ignoring ON COMMIT)
1466 $this->sessionTempTables
= [];
1467 // https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1468 // https://www.postgresql.org/docs/9.4/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1469 $this->namedLocksHeld
= [];
1470 // Session loss implies transaction loss
1471 $this->trxLevel
= 0;
1472 $this->trxAtomicCounter
= 0;
1473 $this->trxIdleCallbacks
= []; // T67263; transaction already lost
1474 $this->trxPreCommitCallbacks
= []; // T67263; transaction already lost
1475 // @note: leave trxRecurringCallbacks in place
1476 if ( $this->trxDoneWrites
) {
1477 $this->trxProfiler
->transactionWritingOut(
1479 $this->getDomainID(),
1481 $this->pendingWriteQueryDuration( self
::ESTIMATE_TOTAL
),
1482 $this->trxWriteAffectedRows
1488 * Clean things up after session (and thus transaction) loss after reconnect
1490 private function handleSessionLossPostconnect() {
1492 // Handle callbacks in trxEndCallbacks, e.g. onTransactionResolution().
1493 // If callback suppression is set then the array will remain unhandled.
1494 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
1495 } catch ( Exception
$ex ) {
1496 // Already logged; move on...
1499 // Handle callbacks in trxRecurringCallbacks, e.g. setTransactionListener()
1500 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
1501 } catch ( Exception
$ex ) {
1502 // Already logged; move on...
1507 * Checks whether the cause of the error is detected to be a timeout.
1509 * It returns false by default, and not all engines support detecting this yet.
1510 * If this returns false, it will be treated as a generic query error.
1512 * @param string $error Error text
1513 * @param int $errno Error number
1516 protected function wasQueryTimeout( $error, $errno ) {
1521 * Report a query error. Log the error, and if neither the object ignore
1522 * flag nor the $tempIgnore flag is set, throw a DBQueryError.
1524 * @param string $error
1526 * @param string $sql
1527 * @param string $fname
1528 * @param bool $tempIgnore
1529 * @throws DBQueryError
1531 public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
1532 if ( $tempIgnore ) {
1533 $this->queryLogger
->debug( "SQL ERROR (ignored): $error\n" );
1535 $exception = $this->getQueryExceptionAndLog( $error, $errno, $sql, $fname );
1542 * @param string $error
1543 * @param string|int $errno
1544 * @param string $sql
1545 * @param string $fname
1548 private function getQueryExceptionAndLog( $error, $errno, $sql, $fname ) {
1549 $sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
1550 $this->queryLogger
->error(
1551 "{fname}\t{db_server}\t{errno}\t{error}\t{sql1line}",
1552 $this->getLogContext( [
1553 'method' => __METHOD__
,
1556 'sql1line' => $sql1line,
1558 'trace' => ( new RuntimeException() )->getTraceAsString()
1561 $this->queryLogger
->debug( "SQL ERROR: " . $error . "\n" );
1562 $wasQueryTimeout = $this->wasQueryTimeout( $error, $errno );
1563 if ( $wasQueryTimeout ) {
1564 $e = new DBQueryTimeoutError( $this, $error, $errno, $sql, $fname );
1566 $e = new DBQueryError( $this, $error, $errno, $sql, $fname );
1572 public function freeResult( $res ) {
1575 public function selectField(
1576 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1578 if ( $var === '*' ) { // sanity
1579 throw new DBUnexpectedError( $this, "Cannot use a * field: got '$var'" );
1582 if ( !is_array( $options ) ) {
1583 $options = [ $options ];
1586 $options['LIMIT'] = 1;
1588 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1589 if ( $res === false ||
!$this->numRows( $res ) ) {
1593 $row = $this->fetchRow( $res );
1595 if ( $row !== false ) {
1596 return reset( $row );
1602 public function selectFieldValues(
1603 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1605 if ( $var === '*' ) { // sanity
1606 throw new DBUnexpectedError( $this, "Cannot use a * field" );
1607 } elseif ( !is_string( $var ) ) { // sanity
1608 throw new DBUnexpectedError( $this, "Cannot use an array of fields" );
1611 if ( !is_array( $options ) ) {
1612 $options = [ $options ];
1615 $res = $this->select( $table, [ 'value' => $var ], $cond, $fname, $options, $join_conds );
1616 if ( $res === false ) {
1621 foreach ( $res as $row ) {
1622 $values[] = $row->value
;
1629 * Returns an optional USE INDEX clause to go after the table, and a
1630 * string to go at the end of the query.
1632 * @param array $options Associative array of options to be turned into
1633 * an SQL query, valid keys are listed in the function.
1635 * @see Database::select()
1637 protected function makeSelectOptions( $options ) {
1638 $preLimitTail = $postLimitTail = '';
1643 foreach ( $options as $key => $option ) {
1644 if ( is_numeric( $key ) ) {
1645 $noKeyOptions[$option] = true;
1649 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1651 $preLimitTail .= $this->makeOrderBy( $options );
1653 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1654 $postLimitTail .= ' FOR UPDATE';
1657 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1658 $postLimitTail .= ' LOCK IN SHARE MODE';
1661 if ( isset( $noKeyOptions['DISTINCT'] ) ||
isset( $noKeyOptions['DISTINCTROW'] ) ) {
1662 $startOpts .= 'DISTINCT';
1665 # Various MySQL extensions
1666 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) {
1667 $startOpts .= ' /*! STRAIGHT_JOIN */';
1670 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) {
1671 $startOpts .= ' HIGH_PRIORITY';
1674 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) {
1675 $startOpts .= ' SQL_BIG_RESULT';
1678 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) {
1679 $startOpts .= ' SQL_BUFFER_RESULT';
1682 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) {
1683 $startOpts .= ' SQL_SMALL_RESULT';
1686 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) {
1687 $startOpts .= ' SQL_CALC_FOUND_ROWS';
1690 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) {
1691 $startOpts .= ' SQL_CACHE';
1694 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) {
1695 $startOpts .= ' SQL_NO_CACHE';
1698 if ( isset( $options['USE INDEX'] ) && is_string( $options['USE INDEX'] ) ) {
1699 $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1703 if ( isset( $options['IGNORE INDEX'] ) && is_string( $options['IGNORE INDEX'] ) ) {
1704 $ignoreIndex = $this->ignoreIndexClause( $options['IGNORE INDEX'] );
1709 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1713 * Returns an optional GROUP BY with an optional HAVING
1715 * @param array $options Associative array of options
1717 * @see Database::select()
1720 protected function makeGroupByWithHaving( $options ) {
1722 if ( isset( $options['GROUP BY'] ) ) {
1723 $gb = is_array( $options['GROUP BY'] )
1724 ?
implode( ',', $options['GROUP BY'] )
1725 : $options['GROUP BY'];
1726 $sql .= ' GROUP BY ' . $gb;
1728 if ( isset( $options['HAVING'] ) ) {
1729 $having = is_array( $options['HAVING'] )
1730 ?
$this->makeList( $options['HAVING'], self
::LIST_AND
)
1731 : $options['HAVING'];
1732 $sql .= ' HAVING ' . $having;
1739 * Returns an optional ORDER BY
1741 * @param array $options Associative array of options
1743 * @see Database::select()
1746 protected function makeOrderBy( $options ) {
1747 if ( isset( $options['ORDER BY'] ) ) {
1748 $ob = is_array( $options['ORDER BY'] )
1749 ?
implode( ',', $options['ORDER BY'] )
1750 : $options['ORDER BY'];
1752 return ' ORDER BY ' . $ob;
1758 public function select(
1759 $table, $vars, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1761 $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
1763 return $this->query( $sql, $fname );
1766 public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__
,
1767 $options = [], $join_conds = []
1769 if ( is_array( $vars ) ) {
1770 $fields = implode( ',', $this->fieldNamesWithAlias( $vars ) );
1775 $options = (array)$options;
1776 $useIndexes = ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1777 ?
$options['USE INDEX']
1780 isset( $options['IGNORE INDEX'] ) &&
1781 is_array( $options['IGNORE INDEX'] )
1783 ?
$options['IGNORE INDEX']
1787 $this->selectOptionsIncludeLocking( $options ) &&
1788 $this->selectFieldsOrOptionsAggregate( $vars, $options )
1790 // Some DB types (postgres/oracle) disallow FOR UPDATE with aggregate
1791 // functions. Discourage use of such queries to encourage compatibility.
1793 $this->deprecationLogger
,
1794 __METHOD__
. ": aggregation used with a locking SELECT ($fname)."
1798 if ( is_array( $table ) ) {
1800 $this->tableNamesWithIndexClauseOrJOIN(
1801 $table, $useIndexes, $ignoreIndexes, $join_conds );
1802 } elseif ( $table != '' ) {
1804 $this->tableNamesWithIndexClauseOrJOIN(
1805 [ $table ], $useIndexes, $ignoreIndexes, [] );
1810 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ) =
1811 $this->makeSelectOptions( $options );
1813 if ( is_array( $conds ) ) {
1814 $conds = $this->makeList( $conds, self
::LIST_AND
);
1817 if ( $conds === null ||
$conds === false ) {
1818 $this->queryLogger
->warning(
1822 . ' with incorrect parameters: $conds must be a string or an array'
1827 if ( $conds === '' ||
$conds === '*' ) {
1828 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex $preLimitTail";
1829 } elseif ( is_string( $conds ) ) {
1830 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex " .
1831 "WHERE $conds $preLimitTail";
1833 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
1836 if ( isset( $options['LIMIT'] ) ) {
1837 $sql = $this->limitResult( $sql, $options['LIMIT'],
1838 $options['OFFSET'] ??
false );
1840 $sql = "$sql $postLimitTail";
1842 if ( isset( $options['EXPLAIN'] ) ) {
1843 $sql = 'EXPLAIN ' . $sql;
1849 public function selectRow( $table, $vars, $conds, $fname = __METHOD__
,
1850 $options = [], $join_conds = []
1852 $options = (array)$options;
1853 $options['LIMIT'] = 1;
1854 $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
1856 if ( $res === false ) {
1860 if ( !$this->numRows( $res ) ) {
1864 $obj = $this->fetchObject( $res );
1869 public function estimateRowCount(
1870 $table, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1872 $conds = $this->normalizeConditions( $conds, $fname );
1873 $column = $this->extractSingleFieldFromList( $var );
1874 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1875 $conds[] = "$column IS NOT NULL";
1878 $res = $this->select(
1879 $table, [ 'rowcount' => 'COUNT(*)' ], $conds, $fname, $options, $join_conds
1881 $row = $res ?
$this->fetchRow( $res ) : [];
1883 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1886 public function selectRowCount(
1887 $tables, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1889 $conds = $this->normalizeConditions( $conds, $fname );
1890 $column = $this->extractSingleFieldFromList( $var );
1891 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1892 $conds[] = "$column IS NOT NULL";
1895 $res = $this->select(
1897 'tmp_count' => $this->buildSelectSubquery(
1906 [ 'rowcount' => 'COUNT(*)' ],
1910 $row = $res ?
$this->fetchRow( $res ) : [];
1912 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1916 * @param string|array $options
1919 private function selectOptionsIncludeLocking( $options ) {
1920 $options = (array)$options;
1921 foreach ( [ 'FOR UPDATE', 'LOCK IN SHARE MODE' ] as $lock ) {
1922 if ( in_array( $lock, $options, true ) ) {
1931 * @param array|string $fields
1932 * @param array|string $options
1935 private function selectFieldsOrOptionsAggregate( $fields, $options ) {
1936 foreach ( (array)$options as $key => $value ) {
1937 if ( is_string( $key ) ) {
1938 if ( preg_match( '/^(?:GROUP BY|HAVING)$/i', $key ) ) {
1941 } elseif ( is_string( $value ) ) {
1942 if ( preg_match( '/^(?:DISTINCT|DISTINCTROW)$/i', $value ) ) {
1948 $regex = '/^(?:COUNT|MIN|MAX|SUM|GROUP_CONCAT|LISTAGG|ARRAY_AGG)\s*\\(/i';
1949 foreach ( (array)$fields as $field ) {
1950 if ( is_string( $field ) && preg_match( $regex, $field ) ) {
1959 * @param array|string $conds
1960 * @param string $fname
1963 final protected function normalizeConditions( $conds, $fname ) {
1964 if ( $conds === null ||
$conds === false ) {
1965 $this->queryLogger
->warning(
1969 . ' with incorrect parameters: $conds must be a string or an array'
1974 if ( !is_array( $conds ) ) {
1975 $conds = ( $conds === '' ) ?
[] : [ $conds ];
1982 * @param array|string $var Field parameter in the style of select()
1983 * @return string|null Column name or null; ignores aliases
1984 * @throws DBUnexpectedError Errors out if multiple columns are given
1986 final protected function extractSingleFieldFromList( $var ) {
1987 if ( is_array( $var ) ) {
1990 } elseif ( count( $var ) == 1 ) {
1991 $column = $var[0] ??
reset( $var );
1993 throw new DBUnexpectedError( $this, __METHOD__
. ': got multiple columns.' );
2002 public function lockForUpdate(
2003 $table, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
2005 if ( !$this->trxLevel
&& !$this->getFlag( self
::DBO_TRX
) ) {
2006 throw new DBUnexpectedError(
2008 __METHOD__
. ': no transaction is active nor is DBO_TRX set'
2012 $options = (array)$options;
2013 $options[] = 'FOR UPDATE';
2015 return $this->selectRowCount( $table, '*', $conds, $fname, $options, $join_conds );
2019 * Removes most variables from an SQL query and replaces them with X or N for numbers.
2020 * It's only slightly flawed. Don't use for anything important.
2022 * @param string $sql A SQL Query
2026 protected static function generalizeSQL( $sql ) {
2027 # This does the same as the regexp below would do, but in such a way
2028 # as to avoid crashing php on some large strings.
2029 # $sql = preg_replace( "/'([^\\\\']|\\\\.)*'|\"([^\\\\\"]|\\\\.)*\"/", "'X'", $sql );
2031 $sql = str_replace( "\\\\", '', $sql );
2032 $sql = str_replace( "\\'", '', $sql );
2033 $sql = str_replace( "\\\"", '', $sql );
2034 $sql = preg_replace( "/'.*'/s", "'X'", $sql );
2035 $sql = preg_replace( '/".*"/s', "'X'", $sql );
2037 # All newlines, tabs, etc replaced by single space
2038 $sql = preg_replace( '/\s+/', ' ', $sql );
2041 # except the ones surrounded by characters, e.g. l10n
2042 $sql = preg_replace( '/-?\d+(,-?\d+)+/s', 'N,...,N', $sql );
2043 $sql = preg_replace( '/(?<![a-zA-Z])-?\d+(?![a-zA-Z])/s', 'N', $sql );
2048 public function fieldExists( $table, $field, $fname = __METHOD__
) {
2049 $info = $this->fieldInfo( $table, $field );
2054 public function indexExists( $table, $index, $fname = __METHOD__
) {
2055 if ( !$this->tableExists( $table ) ) {
2059 $info = $this->indexInfo( $table, $index, $fname );
2060 if ( is_null( $info ) ) {
2063 return $info !== false;
2067 abstract public function tableExists( $table, $fname = __METHOD__
);
2069 public function indexUnique( $table, $index ) {
2070 $indexInfo = $this->indexInfo( $table, $index );
2072 if ( !$indexInfo ) {
2076 return !$indexInfo[0]->Non_unique
;
2080 * Helper for Database::insert().
2082 * @param array $options
2085 protected function makeInsertOptions( $options ) {
2086 return implode( ' ', $options );
2089 public function insert( $table, $a, $fname = __METHOD__
, $options = [] ) {
2090 # No rows to insert, easy just return now
2091 if ( !count( $a ) ) {
2095 $table = $this->tableName( $table );
2097 if ( !is_array( $options ) ) {
2098 $options = [ $options ];
2101 $options = $this->makeInsertOptions( $options );
2103 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
2105 $keys = array_keys( $a[0] );
2108 $keys = array_keys( $a );
2111 $sql = 'INSERT ' . $options .
2112 " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
2116 foreach ( $a as $row ) {
2122 $sql .= '(' . $this->makeList( $row ) . ')';
2125 $sql .= '(' . $this->makeList( $a ) . ')';
2128 $this->query( $sql, $fname );
2134 * Make UPDATE options array for Database::makeUpdateOptions
2136 * @param array $options
2139 protected function makeUpdateOptionsArray( $options ) {
2140 if ( !is_array( $options ) ) {
2141 $options = [ $options ];
2146 if ( in_array( 'IGNORE', $options ) ) {
2154 * Make UPDATE options for the Database::update function
2156 * @param array $options The options passed to Database::update
2159 protected function makeUpdateOptions( $options ) {
2160 $opts = $this->makeUpdateOptionsArray( $options );
2162 return implode( ' ', $opts );
2165 public function update( $table, $values, $conds, $fname = __METHOD__
, $options = [] ) {
2166 $table = $this->tableName( $table );
2167 $opts = $this->makeUpdateOptions( $options );
2168 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, self
::LIST_SET
);
2170 if ( $conds !== [] && $conds !== '*' ) {
2171 $sql .= " WHERE " . $this->makeList( $conds, self
::LIST_AND
);
2174 $this->query( $sql, $fname );
2179 public function makeList( $a, $mode = self
::LIST_COMMA
) {
2180 if ( !is_array( $a ) ) {
2181 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
2187 foreach ( $a as $field => $value ) {
2189 if ( $mode == self
::LIST_AND
) {
2191 } elseif ( $mode == self
::LIST_OR
) {
2200 if ( ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_numeric( $field ) ) {
2201 $list .= "($value)";
2202 } elseif ( $mode == self
::LIST_SET
&& is_numeric( $field ) ) {
2205 ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_array( $value )
2207 // Remove null from array to be handled separately if found
2208 $includeNull = false;
2209 foreach ( array_keys( $value, null, true ) as $nullKey ) {
2210 $includeNull = true;
2211 unset( $value[$nullKey] );
2213 if ( count( $value ) == 0 && !$includeNull ) {
2214 throw new InvalidArgumentException(
2215 __METHOD__
. ": empty input for field $field" );
2216 } elseif ( count( $value ) == 0 ) {
2217 // only check if $field is null
2218 $list .= "$field IS NULL";
2220 // IN clause contains at least one valid element
2221 if ( $includeNull ) {
2222 // Group subconditions to ensure correct precedence
2225 if ( count( $value ) == 1 ) {
2226 // Special-case single values, as IN isn't terribly efficient
2227 // Don't necessarily assume the single key is 0; we don't
2228 // enforce linear numeric ordering on other arrays here.
2229 $value = array_values( $value )[0];
2230 $list .= $field . " = " . $this->addQuotes( $value );
2232 $list .= $field . " IN (" . $this->makeList( $value ) . ") ";
2234 // if null present in array, append IS NULL
2235 if ( $includeNull ) {
2236 $list .= " OR $field IS NULL)";
2239 } elseif ( $value === null ) {
2240 if ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) {
2241 $list .= "$field IS ";
2242 } elseif ( $mode == self
::LIST_SET
) {
2243 $list .= "$field = ";
2248 $mode == self
::LIST_AND ||
$mode == self
::LIST_OR ||
$mode == self
::LIST_SET
2250 $list .= "$field = ";
2252 $list .= $mode == self
::LIST_NAMES ?
$value : $this->addQuotes( $value );
2259 public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
2262 foreach ( $data as $base => $sub ) {
2263 if ( count( $sub ) ) {
2264 $conds[] = $this->makeList(
2265 [ $baseKey => $base, $subKey => array_keys( $sub ) ],
2271 return $this->makeList( $conds, self
::LIST_OR
);
2273 // Nothing to search for...
2278 public function aggregateValue( $valuedata, $valuename = 'value' ) {
2282 public function bitNot( $field ) {
2286 public function bitAnd( $fieldLeft, $fieldRight ) {
2287 return "($fieldLeft & $fieldRight)";
2290 public function bitOr( $fieldLeft, $fieldRight ) {
2291 return "($fieldLeft | $fieldRight)";
2294 public function buildConcat( $stringList ) {
2295 return 'CONCAT(' . implode( ',', $stringList ) . ')';
2298 public function buildGroupConcatField(
2299 $delim, $table, $field, $conds = '', $join_conds = []
2301 $fld = "GROUP_CONCAT($field SEPARATOR " . $this->addQuotes( $delim ) . ')';
2303 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
2306 public function buildSubstring( $input, $startPosition, $length = null ) {
2307 $this->assertBuildSubstringParams( $startPosition, $length );
2308 $functionBody = "$input FROM $startPosition";
2309 if ( $length !== null ) {
2310 $functionBody .= " FOR $length";
2312 return 'SUBSTRING(' . $functionBody . ')';
2316 * Check type and bounds for parameters to self::buildSubstring()
2318 * All supported databases have substring functions that behave the same for
2319 * positive $startPosition and non-negative $length, but behaviors differ when
2320 * given 0 or negative $startPosition or negative $length. The simplest
2321 * solution to that is to just forbid those values.
2323 * @param int $startPosition
2324 * @param int|null $length
2327 protected function assertBuildSubstringParams( $startPosition, $length ) {
2328 if ( !is_int( $startPosition ) ||
$startPosition <= 0 ) {
2329 throw new InvalidArgumentException(
2330 '$startPosition must be a positive integer'
2333 if ( !( is_int( $length ) && $length >= 0 ||
$length === null ) ) {
2334 throw new InvalidArgumentException(
2335 '$length must be null or an integer greater than or equal to 0'
2340 public function buildStringCast( $field ) {
2341 // In theory this should work for any standards-compliant
2342 // SQL implementation, although it may not be the best way to do it.
2343 return "CAST( $field AS CHARACTER )";
2346 public function buildIntegerCast( $field ) {
2347 return 'CAST( ' . $field . ' AS INTEGER )';
2350 public function buildSelectSubquery(
2351 $table, $vars, $conds = '', $fname = __METHOD__
,
2352 $options = [], $join_conds = []
2354 return new Subquery(
2355 $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds )
2359 public function databasesAreIndependent() {
2363 final public function selectDB( $db ) {
2364 $this->selectDomain( new DatabaseDomain(
2366 $this->currentDomain
->getSchema(),
2367 $this->currentDomain
->getTablePrefix()
2373 final public function selectDomain( $domain ) {
2374 $this->doSelectDomain( DatabaseDomain
::newFromId( $domain ) );
2377 protected function doSelectDomain( DatabaseDomain
$domain ) {
2378 $this->currentDomain
= $domain;
2381 public function getDBname() {
2382 return $this->currentDomain
->getDatabase();
2385 public function getServer() {
2386 return $this->server
;
2389 public function tableName( $name, $format = 'quoted' ) {
2390 if ( $name instanceof Subquery
) {
2391 throw new DBUnexpectedError(
2393 __METHOD__
. ': got Subquery instance when expecting a string.'
2397 # Skip the entire process when we have a string quoted on both ends.
2398 # Note that we check the end so that we will still quote any use of
2399 # use of `database`.table. But won't break things if someone wants
2400 # to query a database table with a dot in the name.
2401 if ( $this->isQuotedIdentifier( $name ) ) {
2405 # Lets test for any bits of text that should never show up in a table
2406 # name. Basically anything like JOIN or ON which are actually part of
2407 # SQL queries, but may end up inside of the table value to combine
2408 # sql. Such as how the API is doing.
2409 # Note that we use a whitespace test rather than a \b test to avoid
2410 # any remote case where a word like on may be inside of a table name
2411 # surrounded by symbols which may be considered word breaks.
2412 if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) {
2413 $this->queryLogger
->warning(
2414 __METHOD__
. ": use of subqueries is not supported this way.",
2415 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
2421 # Split database and table into proper variables.
2422 list( $database, $schema, $prefix, $table ) = $this->qualifiedTableComponents( $name );
2424 # Quote $table and apply the prefix if not quoted.
2425 # $tableName might be empty if this is called from Database::replaceVars()
2426 $tableName = "{$prefix}{$table}";
2427 if ( $format === 'quoted'
2428 && !$this->isQuotedIdentifier( $tableName )
2429 && $tableName !== ''
2431 $tableName = $this->addIdentifierQuotes( $tableName );
2434 # Quote $schema and $database and merge them with the table name if needed
2435 $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
2436 $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
2442 * Get the table components needed for a query given the currently selected database
2444 * @param string $name Table name in the form of db.schema.table, db.table, or table
2445 * @return array (DB name or "" for default, schema name, table prefix, table name)
2447 protected function qualifiedTableComponents( $name ) {
2448 # We reverse the explode so that database.table and table both output the correct table.
2449 $dbDetails = explode( '.', $name, 3 );
2450 if ( count( $dbDetails ) == 3 ) {
2451 list( $database, $schema, $table ) = $dbDetails;
2452 # We don't want any prefix added in this case
2454 } elseif ( count( $dbDetails ) == 2 ) {
2455 list( $database, $table ) = $dbDetails;
2456 # We don't want any prefix added in this case
2458 # In dbs that support it, $database may actually be the schema
2459 # but that doesn't affect any of the functionality here
2462 list( $table ) = $dbDetails;
2463 if ( isset( $this->tableAliases
[$table] ) ) {
2464 $database = $this->tableAliases
[$table]['dbname'];
2465 $schema = is_string( $this->tableAliases
[$table]['schema'] )
2466 ?
$this->tableAliases
[$table]['schema']
2467 : $this->relationSchemaQualifier();
2468 $prefix = is_string( $this->tableAliases
[$table]['prefix'] )
2469 ?
$this->tableAliases
[$table]['prefix']
2470 : $this->tablePrefix();
2473 $schema = $this->relationSchemaQualifier(); # Default schema
2474 $prefix = $this->tablePrefix(); # Default prefix
2478 return [ $database, $schema, $prefix, $table ];
2482 * @param string|null $namespace Database or schema
2483 * @param string $relation Name of table, view, sequence, etc...
2484 * @param string $format One of (raw, quoted)
2485 * @return string Relation name with quoted and merged $namespace as needed
2487 private function prependDatabaseOrSchema( $namespace, $relation, $format ) {
2488 if ( strlen( $namespace ) ) {
2489 if ( $format === 'quoted' && !$this->isQuotedIdentifier( $namespace ) ) {
2490 $namespace = $this->addIdentifierQuotes( $namespace );
2492 $relation = $namespace . '.' . $relation;
2498 public function tableNames() {
2499 $inArray = func_get_args();
2502 foreach ( $inArray as $name ) {
2503 $retVal[$name] = $this->tableName( $name );
2509 public function tableNamesN() {
2510 $inArray = func_get_args();
2513 foreach ( $inArray as $name ) {
2514 $retVal[] = $this->tableName( $name );
2521 * Get an aliased table name
2523 * This returns strings like "tableName AS newTableName" for aliased tables
2524 * and "(SELECT * from tableA) newTablename" for subqueries (e.g. derived tables)
2526 * @see Database::tableName()
2527 * @param string|Subquery $table Table name or object with a 'sql' field
2528 * @param string|bool $alias Table alias (optional)
2529 * @return string SQL name for aliased table. Will not alias a table to its own name
2531 protected function tableNameWithAlias( $table, $alias = false ) {
2532 if ( is_string( $table ) ) {
2533 $quotedTable = $this->tableName( $table );
2534 } elseif ( $table instanceof Subquery
) {
2535 $quotedTable = (string)$table;
2537 throw new InvalidArgumentException( "Table must be a string or Subquery." );
2540 if ( !strlen( $alias ) ||
$alias === $table ) {
2541 if ( $table instanceof Subquery
) {
2542 throw new InvalidArgumentException( "Subquery table missing alias." );
2545 return $quotedTable;
2547 return $quotedTable . ' ' . $this->addIdentifierQuotes( $alias );
2552 * Gets an array of aliased table names
2554 * @param array $tables [ [alias] => table ]
2555 * @return string[] See tableNameWithAlias()
2557 protected function tableNamesWithAlias( $tables ) {
2559 foreach ( $tables as $alias => $table ) {
2560 if ( is_numeric( $alias ) ) {
2563 $retval[] = $this->tableNameWithAlias( $table, $alias );
2570 * Get an aliased field name
2571 * e.g. fieldName AS newFieldName
2573 * @param string $name Field name
2574 * @param string|bool $alias Alias (optional)
2575 * @return string SQL name for aliased field. Will not alias a field to its own name
2577 protected function fieldNameWithAlias( $name, $alias = false ) {
2578 if ( !$alias ||
(string)$alias === (string)$name ) {
2581 return $name . ' AS ' . $this->addIdentifierQuotes( $alias ); // PostgreSQL needs AS
2586 * Gets an array of aliased field names
2588 * @param array $fields [ [alias] => field ]
2589 * @return string[] See fieldNameWithAlias()
2591 protected function fieldNamesWithAlias( $fields ) {
2593 foreach ( $fields as $alias => $field ) {
2594 if ( is_numeric( $alias ) ) {
2597 $retval[] = $this->fieldNameWithAlias( $field, $alias );
2604 * Get the aliased table name clause for a FROM clause
2605 * which might have a JOIN and/or USE INDEX or IGNORE INDEX clause
2607 * @param array $tables ( [alias] => table )
2608 * @param array $use_index Same as for select()
2609 * @param array $ignore_index Same as for select()
2610 * @param array $join_conds Same as for select()
2613 protected function tableNamesWithIndexClauseOrJOIN(
2614 $tables, $use_index = [], $ignore_index = [], $join_conds = []
2618 $use_index = (array)$use_index;
2619 $ignore_index = (array)$ignore_index;
2620 $join_conds = (array)$join_conds;
2622 foreach ( $tables as $alias => $table ) {
2623 if ( !is_string( $alias ) ) {
2624 // No alias? Set it equal to the table name
2628 if ( is_array( $table ) ) {
2629 // A parenthesized group
2630 if ( count( $table ) > 1 ) {
2631 $joinedTable = '(' .
2632 $this->tableNamesWithIndexClauseOrJOIN(
2633 $table, $use_index, $ignore_index, $join_conds ) . ')';
2636 $innerTable = reset( $table );
2637 $innerAlias = key( $table );
2638 $joinedTable = $this->tableNameWithAlias(
2640 is_string( $innerAlias ) ?
$innerAlias : $innerTable
2644 $joinedTable = $this->tableNameWithAlias( $table, $alias );
2647 // Is there a JOIN clause for this table?
2648 if ( isset( $join_conds[$alias] ) ) {
2649 list( $joinType, $conds ) = $join_conds[$alias];
2650 $tableClause = $joinType;
2651 $tableClause .= ' ' . $joinedTable;
2652 if ( isset( $use_index[$alias] ) ) { // has USE INDEX?
2653 $use = $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) );
2655 $tableClause .= ' ' . $use;
2658 if ( isset( $ignore_index[$alias] ) ) { // has IGNORE INDEX?
2659 $ignore = $this->ignoreIndexClause(
2660 implode( ',', (array)$ignore_index[$alias] ) );
2661 if ( $ignore != '' ) {
2662 $tableClause .= ' ' . $ignore;
2665 $on = $this->makeList( (array)$conds, self
::LIST_AND
);
2667 $tableClause .= ' ON (' . $on . ')';
2670 $retJOIN[] = $tableClause;
2671 } elseif ( isset( $use_index[$alias] ) ) {
2672 // Is there an INDEX clause for this table?
2673 $tableClause = $joinedTable;
2674 $tableClause .= ' ' . $this->useIndexClause(
2675 implode( ',', (array)$use_index[$alias] )
2678 $ret[] = $tableClause;
2679 } elseif ( isset( $ignore_index[$alias] ) ) {
2680 // Is there an INDEX clause for this table?
2681 $tableClause = $joinedTable;
2682 $tableClause .= ' ' . $this->ignoreIndexClause(
2683 implode( ',', (array)$ignore_index[$alias] )
2686 $ret[] = $tableClause;
2688 $tableClause = $joinedTable;
2690 $ret[] = $tableClause;
2694 // We can't separate explicit JOIN clauses with ',', use ' ' for those
2695 $implicitJoins = $ret ?
implode( ',', $ret ) : "";
2696 $explicitJoins = $retJOIN ?
implode( ' ', $retJOIN ) : "";
2698 // Compile our final table clause
2699 return implode( ' ', [ $implicitJoins, $explicitJoins ] );
2703 * Allows for index remapping in queries where this is not consistent across DBMS
2705 * @param string $index
2708 protected function indexName( $index ) {
2709 return $this->indexAliases
[$index] ??
$index;
2712 public function addQuotes( $s ) {
2713 if ( $s instanceof Blob
) {
2716 if ( $s === null ) {
2718 } elseif ( is_bool( $s ) ) {
2721 # This will also quote numeric values. This should be harmless,
2722 # and protects against weird problems that occur when they really
2723 # _are_ strings such as article titles and string->number->string
2724 # conversion is not 1:1.
2725 return "'" . $this->strencode( $s ) . "'";
2729 public function addIdentifierQuotes( $s ) {
2730 return '"' . str_replace( '"', '""', $s ) . '"';
2734 * Returns if the given identifier looks quoted or not according to
2735 * the database convention for quoting identifiers .
2737 * @note Do not use this to determine if untrusted input is safe.
2738 * A malicious user can trick this function.
2739 * @param string $name
2742 public function isQuotedIdentifier( $name ) {
2743 return $name[0] == '"' && substr( $name, -1, 1 ) == '"';
2748 * @param string $escapeChar
2751 protected function escapeLikeInternal( $s, $escapeChar = '`' ) {
2752 return str_replace( [ $escapeChar, '%', '_' ],
2753 [ "{$escapeChar}{$escapeChar}", "{$escapeChar}%", "{$escapeChar}_" ],
2757 public function buildLike() {
2758 $params = func_get_args();
2760 if ( count( $params ) > 0 && is_array( $params[0] ) ) {
2761 $params = $params[0];
2766 // We use ` instead of \ as the default LIKE escape character, since addQuotes()
2767 // may escape backslashes, creating problems of double escaping. The `
2768 // character has good cross-DBMS compatibility, avoiding special operators
2769 // in MS SQL like ^ and %
2772 foreach ( $params as $value ) {
2773 if ( $value instanceof LikeMatch
) {
2774 $s .= $value->toString();
2776 $s .= $this->escapeLikeInternal( $value, $escapeChar );
2781 $this->addQuotes( $s ) . ' ESCAPE ' . $this->addQuotes( $escapeChar ) . ' ';
2784 public function anyChar() {
2785 return new LikeMatch( '_' );
2788 public function anyString() {
2789 return new LikeMatch( '%' );
2792 public function nextSequenceValue( $seqName ) {
2797 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
2798 * is only needed because a) MySQL must be as efficient as possible due to
2799 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2800 * which index to pick. Anyway, other databases might have different
2801 * indexes on a given table. So don't bother overriding this unless you're
2803 * @param string $index
2806 public function useIndexClause( $index ) {
2811 * IGNORE INDEX clause. Unlikely to be useful for anything but MySQL. This
2812 * is only needed because a) MySQL must be as efficient as possible due to
2813 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2814 * which index to pick. Anyway, other databases might have different
2815 * indexes on a given table. So don't bother overriding this unless you're
2817 * @param string $index
2820 public function ignoreIndexClause( $index ) {
2824 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__
) {
2825 if ( count( $rows ) == 0 ) {
2829 $uniqueIndexes = (array)$uniqueIndexes;
2831 if ( !is_array( reset( $rows ) ) ) {
2836 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2837 $affectedRowCount = 0;
2838 foreach ( $rows as $row ) {
2839 // Delete rows which collide with this one
2840 $indexWhereClauses = [];
2841 foreach ( $uniqueIndexes as $index ) {
2842 $indexColumns = (array)$index;
2843 $indexRowValues = array_intersect_key( $row, array_flip( $indexColumns ) );
2844 if ( count( $indexRowValues ) != count( $indexColumns ) ) {
2845 throw new DBUnexpectedError(
2847 'New record does not provide all values for unique key (' .
2848 implode( ', ', $indexColumns ) . ')'
2850 } elseif ( in_array( null, $indexRowValues, true ) ) {
2851 throw new DBUnexpectedError(
2853 'New record has a null value for unique key (' .
2854 implode( ', ', $indexColumns ) . ')'
2857 $indexWhereClauses[] = $this->makeList( $indexRowValues, LIST_AND
);
2860 if ( $indexWhereClauses ) {
2861 $this->delete( $table, $this->makeList( $indexWhereClauses, LIST_OR
), $fname );
2862 $affectedRowCount +
= $this->affectedRows();
2865 // Now insert the row
2866 $this->insert( $table, $row, $fname );
2867 $affectedRowCount +
= $this->affectedRows();
2869 $this->endAtomic( $fname );
2870 $this->affectedRowCount
= $affectedRowCount;
2871 } catch ( Exception
$e ) {
2872 $this->cancelAtomic( $fname );
2878 * REPLACE query wrapper for MySQL and SQLite, which have a native REPLACE
2881 * @param string $table Table name
2882 * @param array|string $rows Row(s) to insert
2883 * @param string $fname Caller function name
2885 protected function nativeReplace( $table, $rows, $fname ) {
2886 $table = $this->tableName( $table );
2889 if ( !is_array( reset( $rows ) ) ) {
2893 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES ';
2896 foreach ( $rows as $row ) {
2903 $sql .= '(' . $this->makeList( $row ) . ')';
2906 $this->query( $sql, $fname );
2909 public function upsert( $table, array $rows, $uniqueIndexes, array $set,
2912 if ( $rows === [] ) {
2913 return true; // nothing to do
2916 $uniqueIndexes = (array)$uniqueIndexes;
2917 if ( !is_array( reset( $rows ) ) ) {
2921 if ( count( $uniqueIndexes ) ) {
2922 $clauses = []; // list WHERE clauses that each identify a single row
2923 foreach ( $rows as $row ) {
2924 foreach ( $uniqueIndexes as $index ) {
2925 $index = is_array( $index ) ?
$index : [ $index ]; // columns
2926 $rowKey = []; // unique key to this row
2927 foreach ( $index as $column ) {
2928 $rowKey[$column] = $row[$column];
2930 $clauses[] = $this->makeList( $rowKey, self
::LIST_AND
);
2933 $where = [ $this->makeList( $clauses, self
::LIST_OR
) ];
2938 $affectedRowCount = 0;
2940 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2941 # Update any existing conflicting row(s)
2942 if ( $where !== false ) {
2943 $this->update( $table, $set, $where, $fname );
2944 $affectedRowCount +
= $this->affectedRows();
2946 # Now insert any non-conflicting row(s)
2947 $this->insert( $table, $rows, $fname, [ 'IGNORE' ] );
2948 $affectedRowCount +
= $this->affectedRows();
2949 $this->endAtomic( $fname );
2950 $this->affectedRowCount
= $affectedRowCount;
2951 } catch ( Exception
$e ) {
2952 $this->cancelAtomic( $fname );
2959 public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
2963 throw new DBUnexpectedError( $this, __METHOD__
. ' called with empty $conds' );
2966 $delTable = $this->tableName( $delTable );
2967 $joinTable = $this->tableName( $joinTable );
2968 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
2969 if ( $conds != '*' ) {
2970 $sql .= 'WHERE ' . $this->makeList( $conds, self
::LIST_AND
);
2974 $this->query( $sql, $fname );
2977 public function textFieldSize( $table, $field ) {
2978 $table = $this->tableName( $table );
2979 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\";";
2980 $res = $this->query( $sql, __METHOD__
);
2981 $row = $this->fetchObject( $res );
2985 if ( preg_match( '/\((.*)\)/', $row->Type
, $m ) ) {
2994 public function delete( $table, $conds, $fname = __METHOD__
) {
2996 throw new DBUnexpectedError( $this, __METHOD__
. ' called with no conditions' );
2999 $table = $this->tableName( $table );
3000 $sql = "DELETE FROM $table";
3002 if ( $conds != '*' ) {
3003 if ( is_array( $conds ) ) {
3004 $conds = $this->makeList( $conds, self
::LIST_AND
);
3006 $sql .= ' WHERE ' . $conds;
3009 $this->query( $sql, $fname );
3014 final public function insertSelect(
3015 $destTable, $srcTable, $varMap, $conds,
3016 $fname = __METHOD__
, $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3018 static $hints = [ 'NO_AUTO_COLUMNS' ];
3020 $insertOptions = (array)$insertOptions;
3021 $selectOptions = (array)$selectOptions;
3023 if ( $this->cliMode
&& $this->isInsertSelectSafe( $insertOptions, $selectOptions ) ) {
3024 // For massive migrations with downtime, we don't want to select everything
3025 // into memory and OOM, so do all this native on the server side if possible.
3026 $this->nativeInsertSelect(
3032 array_diff( $insertOptions, $hints ),
3037 $this->nonNativeInsertSelect(
3043 array_diff( $insertOptions, $hints ),
3053 * @param array $insertOptions INSERT options
3054 * @param array $selectOptions SELECT options
3055 * @return bool Whether an INSERT SELECT with these options will be replication safe
3058 protected function isInsertSelectSafe( array $insertOptions, array $selectOptions ) {
3063 * Implementation of insertSelect() based on select() and insert()
3065 * @see IDatabase::insertSelect()
3067 * @param string $destTable
3068 * @param string|array $srcTable
3069 * @param array $varMap
3070 * @param array $conds
3071 * @param string $fname
3072 * @param array $insertOptions
3073 * @param array $selectOptions
3074 * @param array $selectJoinConds
3076 protected function nonNativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3077 $fname = __METHOD__
,
3078 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3080 // For web requests, do a locking SELECT and then INSERT. This puts the SELECT burden
3081 // on only the master (without needing row-based-replication). It also makes it easy to
3082 // know how big the INSERT is going to be.
3084 foreach ( $varMap as $dstColumn => $sourceColumnOrSql ) {
3085 $fields[] = $this->fieldNameWithAlias( $sourceColumnOrSql, $dstColumn );
3087 $selectOptions[] = 'FOR UPDATE';
3088 $res = $this->select(
3089 $srcTable, implode( ',', $fields ), $conds, $fname, $selectOptions, $selectJoinConds
3096 $affectedRowCount = 0;
3097 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
3100 foreach ( $res as $row ) {
3101 $rows[] = (array)$row;
3103 // Avoid inserts that are too huge
3104 if ( count( $rows ) >= $this->nonNativeInsertSelectBatchSize
) {
3105 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
3109 $affectedRowCount +
= $this->affectedRows();
3113 if ( $rows && $ok ) {
3114 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
3116 $affectedRowCount +
= $this->affectedRows();
3120 $this->endAtomic( $fname );
3121 $this->affectedRowCount
= $affectedRowCount;
3123 $this->cancelAtomic( $fname );
3125 } catch ( Exception
$e ) {
3126 $this->cancelAtomic( $fname );
3132 * Native server-side implementation of insertSelect() for situations where
3133 * we don't want to select everything into memory
3135 * @see IDatabase::insertSelect()
3136 * @param string $destTable
3137 * @param string|array $srcTable
3138 * @param array $varMap
3139 * @param array $conds
3140 * @param string $fname
3141 * @param array $insertOptions
3142 * @param array $selectOptions
3143 * @param array $selectJoinConds
3145 protected function nativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3146 $fname = __METHOD__
,
3147 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3149 $destTable = $this->tableName( $destTable );
3151 if ( !is_array( $insertOptions ) ) {
3152 $insertOptions = [ $insertOptions ];
3155 $insertOptions = $this->makeInsertOptions( $insertOptions );
3157 $selectSql = $this->selectSQLText(
3159 array_values( $varMap ),
3166 $sql = "INSERT $insertOptions" .
3167 " INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ') ' .
3170 $this->query( $sql, $fname );
3174 * Construct a LIMIT query with optional offset. This is used for query
3175 * pages. The SQL should be adjusted so that only the first $limit rows
3176 * are returned. If $offset is provided as well, then the first $offset
3177 * rows should be discarded, and the next $limit rows should be returned.
3178 * If the result of the query is not ordered, then the rows to be returned
3179 * are theoretically arbitrary.
3181 * $sql is expected to be a SELECT, if that makes a difference.
3183 * The version provided by default works in MySQL and SQLite. It will very
3184 * likely need to be overridden for most other DBMSes.
3186 * @param string $sql SQL query we will append the limit too
3187 * @param int $limit The SQL limit
3188 * @param int|bool $offset The SQL offset (default false)
3189 * @throws DBUnexpectedError
3192 public function limitResult( $sql, $limit, $offset = false ) {
3193 if ( !is_numeric( $limit ) ) {
3194 throw new DBUnexpectedError( $this,
3195 "Invalid non-numeric limit passed to limitResult()\n" );
3198 return "$sql LIMIT "
3199 . ( ( is_numeric( $offset ) && $offset != 0 ) ?
"{$offset}," : "" )
3203 public function unionSupportsOrderAndLimit() {
3204 return true; // True for almost every DB supported
3207 public function unionQueries( $sqls, $all ) {
3208 $glue = $all ?
') UNION ALL (' : ') UNION (';
3210 return '(' . implode( $glue, $sqls ) . ')';
3213 public function unionConditionPermutations(
3214 $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__
,
3215 $options = [], $join_conds = []
3217 // First, build the Cartesian product of $permute_conds
3219 foreach ( $permute_conds as $field => $values ) {
3221 // Skip empty $values
3224 $values = array_unique( $values ); // For sanity
3226 foreach ( $conds as $cond ) {
3227 foreach ( $values as $value ) {
3228 $cond[$field] = $value;
3229 $newConds[] = $cond; // Arrays are by-value, not by-reference, so this works
3235 $extra_conds = $extra_conds === '' ?
[] : (array)$extra_conds;
3237 // If there's just one condition and no subordering, hand off to
3238 // selectSQLText directly.
3239 if ( count( $conds ) === 1 &&
3240 ( !isset( $options['INNER ORDER BY'] ) ||
!$this->unionSupportsOrderAndLimit() )
3242 return $this->selectSQLText(
3243 $table, $vars, $conds[0] +
$extra_conds, $fname, $options, $join_conds
3247 // Otherwise, we need to pull out the order and limit to apply after
3248 // the union. Then build the SQL queries for each set of conditions in
3249 // $conds. Then union them together (using UNION ALL, because the
3250 // product *should* already be distinct).
3251 $orderBy = $this->makeOrderBy( $options );
3252 $limit = $options['LIMIT'] ??
null;
3253 $offset = $options['OFFSET'] ??
false;
3254 $all = empty( $options['NOTALL'] ) && !in_array( 'NOTALL', $options );
3255 if ( !$this->unionSupportsOrderAndLimit() ) {
3256 unset( $options['ORDER BY'], $options['LIMIT'], $options['OFFSET'] );
3258 if ( array_key_exists( 'INNER ORDER BY', $options ) ) {
3259 $options['ORDER BY'] = $options['INNER ORDER BY'];
3261 if ( $limit !== null && is_numeric( $offset ) && $offset != 0 ) {
3262 // We need to increase the limit by the offset rather than
3263 // using the offset directly, otherwise it'll skip incorrectly
3264 // in the subqueries.
3265 $options['LIMIT'] = $limit +
$offset;
3266 unset( $options['OFFSET'] );
3271 foreach ( $conds as $cond ) {
3272 $sqls[] = $this->selectSQLText(
3273 $table, $vars, $cond +
$extra_conds, $fname, $options, $join_conds
3276 $sql = $this->unionQueries( $sqls, $all ) . $orderBy;
3277 if ( $limit !== null ) {
3278 $sql = $this->limitResult( $sql, $limit, $offset );
3284 public function conditional( $cond, $trueVal, $falseVal ) {
3285 if ( is_array( $cond ) ) {
3286 $cond = $this->makeList( $cond, self
::LIST_AND
);
3289 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
3292 public function strreplace( $orig, $old, $new ) {
3293 return "REPLACE({$orig}, {$old}, {$new})";
3296 public function getServerUptime() {
3300 public function wasDeadlock() {
3304 public function wasLockTimeout() {
3308 public function wasConnectionLoss() {
3309 return $this->wasConnectionError( $this->lastErrno() );
3312 public function wasReadOnlyError() {
3316 public function wasErrorReissuable() {
3318 $this->wasDeadlock() ||
3319 $this->wasLockTimeout() ||
3320 $this->wasConnectionLoss()
3325 * Do not use this method outside of Database/DBError classes
3327 * @param int|string $errno
3328 * @return bool Whether the given query error was a connection drop
3330 public function wasConnectionError( $errno ) {
3335 * @return bool Whether it is known that the last query error only caused statement rollback
3336 * @note This is for backwards compatibility for callers catching DBError exceptions in
3337 * order to ignore problems like duplicate key errors or foriegn key violations
3340 protected function wasKnownStatementRollbackError() {
3341 return false; // don't know; it could have caused a transaction rollback
3344 public function deadlockLoop() {
3345 $args = func_get_args();
3346 $function = array_shift( $args );
3347 $tries = self
::DEADLOCK_TRIES
;
3349 $this->begin( __METHOD__
);
3352 /** @var Exception $e */
3356 $retVal = $function( ...$args );
3358 } catch ( DBQueryError
$e ) {
3359 if ( $this->wasDeadlock() ) {
3360 // Retry after a randomized delay
3361 usleep( mt_rand( self
::DEADLOCK_DELAY_MIN
, self
::DEADLOCK_DELAY_MAX
) );
3363 // Throw the error back up
3367 } while ( --$tries > 0 );
3369 if ( $tries <= 0 ) {
3370 // Too many deadlocks; give up
3371 $this->rollback( __METHOD__
);
3374 $this->commit( __METHOD__
);
3380 public function masterPosWait( DBMasterPos
$pos, $timeout ) {
3381 # Real waits are implemented in the subclass.
3385 public function getReplicaPos() {
3390 public function getMasterPos() {
3395 public function serverIsReadOnly() {
3399 final public function onTransactionResolution( callable
$callback, $fname = __METHOD__
) {
3400 if ( !$this->trxLevel
) {
3401 throw new DBUnexpectedError( $this, "No transaction is active." );
3403 $this->trxEndCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3406 final public function onTransactionCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3407 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3408 // Start an implicit transaction similar to how query() does
3409 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3410 $this->trxAutomatic
= true;
3413 $this->trxIdleCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3414 if ( !$this->trxLevel
) {
3415 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_IDLE
);
3419 final public function onTransactionIdle( callable
$callback, $fname = __METHOD__
) {
3420 $this->onTransactionCommitOrIdle( $callback, $fname );
3423 final public function onTransactionPreCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3424 if ( !$this->trxLevel
&& $this->getTransactionRoundId() ) {
3425 // Start an implicit transaction similar to how query() does
3426 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3427 $this->trxAutomatic
= true;
3430 if ( $this->trxLevel
) {
3431 $this->trxPreCommitCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3433 // No transaction is active nor will start implicitly, so make one for this callback
3434 $this->startAtomic( __METHOD__
, self
::ATOMIC_CANCELABLE
);
3437 $this->endAtomic( __METHOD__
);
3438 } catch ( Exception
$e ) {
3439 $this->cancelAtomic( __METHOD__
);
3446 * @return AtomicSectionIdentifier|null ID of the topmost atomic section level
3448 private function currentAtomicSectionId() {
3449 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3450 $levelInfo = end( $this->trxAtomicLevels
);
3452 return $levelInfo[1];
3459 * @param AtomicSectionIdentifier $old
3460 * @param AtomicSectionIdentifier $new
3462 private function reassignCallbacksForSection(
3463 AtomicSectionIdentifier
$old, AtomicSectionIdentifier
$new
3465 foreach ( $this->trxPreCommitCallbacks
as $key => $info ) {
3466 if ( $info[2] === $old ) {
3467 $this->trxPreCommitCallbacks
[$key][2] = $new;
3470 foreach ( $this->trxIdleCallbacks
as $key => $info ) {
3471 if ( $info[2] === $old ) {
3472 $this->trxIdleCallbacks
[$key][2] = $new;
3475 foreach ( $this->trxEndCallbacks
as $key => $info ) {
3476 if ( $info[2] === $old ) {
3477 $this->trxEndCallbacks
[$key][2] = $new;
3483 * @param AtomicSectionIdentifier[] $sectionIds ID of an actual savepoint
3484 * @throws UnexpectedValueException
3486 private function modifyCallbacksForCancel( array $sectionIds ) {
3487 // Cancel the "on commit" callbacks owned by this savepoint
3488 $this->trxIdleCallbacks
= array_filter(
3489 $this->trxIdleCallbacks
,
3490 function ( $entry ) use ( $sectionIds ) {
3491 return !in_array( $entry[2], $sectionIds, true );
3494 $this->trxPreCommitCallbacks
= array_filter(
3495 $this->trxPreCommitCallbacks
,
3496 function ( $entry ) use ( $sectionIds ) {
3497 return !in_array( $entry[2], $sectionIds, true );
3500 // Make "on resolution" callbacks owned by this savepoint to perceive a rollback
3501 foreach ( $this->trxEndCallbacks
as $key => $entry ) {
3502 if ( in_array( $entry[2], $sectionIds, true ) ) {
3503 $callback = $entry[0];
3504 $this->trxEndCallbacks
[$key][0] = function () use ( $callback ) {
3505 return $callback( self
::TRIGGER_ROLLBACK
, $this );
3511 final public function setTransactionListener( $name, callable
$callback = null ) {
3513 $this->trxRecurringCallbacks
[$name] = $callback;
3515 unset( $this->trxRecurringCallbacks
[$name] );
3520 * Whether to disable running of post-COMMIT/ROLLBACK callbacks
3522 * This method should not be used outside of Database/LoadBalancer
3524 * @param bool $suppress
3527 final public function setTrxEndCallbackSuppression( $suppress ) {
3528 $this->trxEndCallbacksSuppressed
= $suppress;
3532 * Actually consume and run any "on transaction idle/resolution" callbacks.
3534 * This method should not be used outside of Database/LoadBalancer
3536 * @param int $trigger IDatabase::TRIGGER_* constant
3537 * @return int Number of callbacks attempted
3541 public function runOnTransactionIdleCallbacks( $trigger ) {
3542 if ( $this->trxLevel
) { // sanity
3543 throw new DBUnexpectedError( $this, __METHOD__
. ': a transaction is still open.' );
3546 if ( $this->trxEndCallbacksSuppressed
) {
3551 $autoTrx = $this->getFlag( self
::DBO_TRX
); // automatic begin() enabled?
3552 /** @var Exception $e */
3553 $e = null; // first exception
3554 do { // callbacks may add callbacks :)
3555 $callbacks = array_merge(
3556 $this->trxIdleCallbacks
,
3557 $this->trxEndCallbacks
// include "transaction resolution" callbacks
3559 $this->trxIdleCallbacks
= []; // consumed (and recursion guard)
3560 $this->trxEndCallbacks
= []; // consumed (recursion guard)
3561 foreach ( $callbacks as $callback ) {
3563 list( $phpCallback ) = $callback;
3564 $this->clearFlag( self
::DBO_TRX
); // make each query its own transaction
3566 call_user_func( $phpCallback, $trigger, $this );
3567 } catch ( Exception
$ex ) {
3568 call_user_func( $this->errorLogger
, $ex );
3570 // Some callbacks may use startAtomic/endAtomic, so make sure
3571 // their transactions are ended so other callbacks don't fail
3572 if ( $this->trxLevel() ) {
3573 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
3577 $this->setFlag( self
::DBO_TRX
); // restore automatic begin()
3579 $this->clearFlag( self
::DBO_TRX
); // restore auto-commit
3583 } while ( count( $this->trxIdleCallbacks
) );
3585 if ( $e instanceof Exception
) {
3586 throw $e; // re-throw any first exception
3593 * Actually consume and run any "on transaction pre-commit" callbacks.
3595 * This method should not be used outside of Database/LoadBalancer
3598 * @return int Number of callbacks attempted
3601 public function runOnTransactionPreCommitCallbacks() {
3604 $e = null; // first exception
3605 do { // callbacks may add callbacks :)
3606 $callbacks = $this->trxPreCommitCallbacks
;
3607 $this->trxPreCommitCallbacks
= []; // consumed (and recursion guard)
3608 foreach ( $callbacks as $callback ) {
3611 list( $phpCallback ) = $callback;
3612 $phpCallback( $this );
3613 } catch ( Exception
$ex ) {
3614 ( $this->errorLogger
)( $ex );
3618 } while ( count( $this->trxPreCommitCallbacks
) );
3620 if ( $e instanceof Exception
) {
3621 throw $e; // re-throw any first exception
3628 * Actually run any "transaction listener" callbacks.
3630 * This method should not be used outside of Database/LoadBalancer
3632 * @param int $trigger IDatabase::TRIGGER_* constant
3636 public function runTransactionListenerCallbacks( $trigger ) {
3637 if ( $this->trxEndCallbacksSuppressed
) {
3641 /** @var Exception $e */
3642 $e = null; // first exception
3644 foreach ( $this->trxRecurringCallbacks
as $phpCallback ) {
3646 $phpCallback( $trigger, $this );
3647 } catch ( Exception
$ex ) {
3648 ( $this->errorLogger
)( $ex );
3653 if ( $e instanceof Exception
) {
3654 throw $e; // re-throw any first exception
3659 * Create a savepoint
3661 * This is used internally to implement atomic sections. It should not be
3665 * @param string $identifier Identifier for the savepoint
3666 * @param string $fname Calling function name
3668 protected function doSavepoint( $identifier, $fname ) {
3669 $this->query( 'SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3673 * Release a savepoint
3675 * This is used internally to implement atomic sections. It should not be
3679 * @param string $identifier Identifier for the savepoint
3680 * @param string $fname Calling function name
3682 protected function doReleaseSavepoint( $identifier, $fname ) {
3683 $this->query( 'RELEASE SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3687 * Rollback to a savepoint
3689 * This is used internally to implement atomic sections. It should not be
3693 * @param string $identifier Identifier for the savepoint
3694 * @param string $fname Calling function name
3696 protected function doRollbackToSavepoint( $identifier, $fname ) {
3697 $this->query( 'ROLLBACK TO SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3701 * @param string $fname
3704 private function nextSavepointId( $fname ) {
3705 $savepointId = self
::$SAVEPOINT_PREFIX . ++
$this->trxAtomicCounter
;
3706 if ( strlen( $savepointId ) > 30 ) {
3707 // 30 == Oracle's identifier length limit (pre 12c)
3708 // With a 22 character prefix, that puts the highest number at 99999999.
3709 throw new DBUnexpectedError(
3711 'There have been an excessively large number of atomic sections in a transaction'
3712 . " started by $this->trxFname (at $fname)"
3716 return $savepointId;
3719 final public function startAtomic(
3720 $fname = __METHOD__
, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3722 $savepointId = $cancelable === self
::ATOMIC_CANCELABLE ? self
::$NOT_APPLICABLE : null;
3724 if ( !$this->trxLevel
) {
3725 $this->begin( $fname, self
::TRANSACTION_INTERNAL
); // sets trxAutomatic
3726 // If DBO_TRX is set, a series of startAtomic/endAtomic pairs will result
3727 // in all changes being in one transaction to keep requests transactional.
3728 if ( $this->getFlag( self
::DBO_TRX
) ) {
3729 // Since writes could happen in between the topmost atomic sections as part
3730 // of the transaction, those sections will need savepoints.
3731 $savepointId = $this->nextSavepointId( $fname );
3732 $this->doSavepoint( $savepointId, $fname );
3734 $this->trxAutomaticAtomic
= true;
3736 } elseif ( $cancelable === self
::ATOMIC_CANCELABLE
) {
3737 $savepointId = $this->nextSavepointId( $fname );
3738 $this->doSavepoint( $savepointId, $fname );
3741 $sectionId = new AtomicSectionIdentifier
;
3742 $this->trxAtomicLevels
[] = [ $fname, $sectionId, $savepointId ];
3743 $this->queryLogger
->debug( 'startAtomic: entering level ' .
3744 ( count( $this->trxAtomicLevels
) - 1 ) . " ($fname)" );
3749 final public function endAtomic( $fname = __METHOD__
) {
3750 if ( !$this->trxLevel ||
!$this->trxAtomicLevels
) {
3751 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)." );
3754 // Check if the current section matches $fname
3755 $pos = count( $this->trxAtomicLevels
) - 1;
3756 list( $savedFname, $sectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3757 $this->queryLogger
->debug( "endAtomic: leaving level $pos ($fname)" );
3759 if ( $savedFname !== $fname ) {
3760 throw new DBUnexpectedError(
3762 "Invalid atomic section ended (got $fname but expected $savedFname)."
3766 // Remove the last section (no need to re-index the array)
3767 array_pop( $this->trxAtomicLevels
);
3769 if ( !$this->trxAtomicLevels
&& $this->trxAutomaticAtomic
) {
3770 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3771 } elseif ( $savepointId !== null && $savepointId !== self
::$NOT_APPLICABLE ) {
3772 $this->doReleaseSavepoint( $savepointId, $fname );
3775 // Hoist callback ownership for callbacks in the section that just ended;
3776 // all callbacks should have an owner that is present in trxAtomicLevels.
3777 $currentSectionId = $this->currentAtomicSectionId();
3778 if ( $currentSectionId ) {
3779 $this->reassignCallbacksForSection( $sectionId, $currentSectionId );
3783 final public function cancelAtomic(
3784 $fname = __METHOD__
, AtomicSectionIdentifier
$sectionId = null
3786 if ( !$this->trxLevel ||
!$this->trxAtomicLevels
) {
3787 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)." );
3790 $excisedFnames = [];
3791 if ( $sectionId !== null ) {
3792 // Find the (last) section with the given $sectionId
3794 foreach ( $this->trxAtomicLevels
as $i => list( $asFname, $asId, $spId ) ) {
3795 if ( $asId === $sectionId ) {
3800 throw new DBUnexpectedError( $this, "Atomic section not found (for $fname)" );
3802 // Remove all descendant sections and re-index the array
3804 $len = count( $this->trxAtomicLevels
);
3805 for ( $i = $pos +
1; $i < $len; ++
$i ) {
3806 $excisedFnames[] = $this->trxAtomicLevels
[$i][0];
3807 $excisedIds[] = $this->trxAtomicLevels
[$i][1];
3809 $this->trxAtomicLevels
= array_slice( $this->trxAtomicLevels
, 0, $pos +
1 );
3810 $this->modifyCallbacksForCancel( $excisedIds );
3813 // Check if the current section matches $fname
3814 $pos = count( $this->trxAtomicLevels
) - 1;
3815 list( $savedFname, $savedSectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3817 if ( $excisedFnames ) {
3818 $this->queryLogger
->debug( "cancelAtomic: canceling level $pos ($savedFname) " .
3819 "and descendants " . implode( ', ', $excisedFnames ) );
3821 $this->queryLogger
->debug( "cancelAtomic: canceling level $pos ($savedFname)" );
3824 if ( $savedFname !== $fname ) {
3825 throw new DBUnexpectedError(
3827 "Invalid atomic section ended (got $fname but expected $savedFname)."
3831 // Remove the last section (no need to re-index the array)
3832 array_pop( $this->trxAtomicLevels
);
3833 $this->modifyCallbacksForCancel( [ $savedSectionId ] );
3835 if ( $savepointId !== null ) {
3836 // Rollback the transaction to the state just before this atomic section
3837 if ( $savepointId === self
::$NOT_APPLICABLE ) {
3838 $this->rollback( $fname, self
::FLUSHING_INTERNAL
);
3840 $this->doRollbackToSavepoint( $savepointId, $fname );
3841 $this->trxStatus
= self
::STATUS_TRX_OK
; // no exception; recovered
3842 $this->trxStatusIgnoredCause
= null;
3844 } elseif ( $this->trxStatus
> self
::STATUS_TRX_ERROR
) {
3845 // Put the transaction into an error state if it's not already in one
3846 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
3847 $this->trxStatusCause
= new DBUnexpectedError(
3849 "Uncancelable atomic section canceled (got $fname)."
3853 $this->affectedRowCount
= 0; // for the sake of consistency
3856 final public function doAtomicSection(
3857 $fname, callable
$callback, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3859 $sectionId = $this->startAtomic( $fname, $cancelable );
3861 $res = $callback( $this, $fname );
3862 } catch ( Exception
$e ) {
3863 $this->cancelAtomic( $fname, $sectionId );
3867 $this->endAtomic( $fname );
3872 final public function begin( $fname = __METHOD__
, $mode = self
::TRANSACTION_EXPLICIT
) {
3873 static $modes = [ self
::TRANSACTION_EXPLICIT
, self
::TRANSACTION_INTERNAL
];
3874 if ( !in_array( $mode, $modes, true ) ) {
3875 throw new DBUnexpectedError( $this, "$fname: invalid mode parameter '$mode'." );
3878 // Protect against mismatched atomic section, transaction nesting, and snapshot loss
3879 if ( $this->trxLevel
) {
3880 if ( $this->trxAtomicLevels
) {
3881 $levels = $this->flatAtomicSectionList();
3882 $msg = "$fname: Got explicit BEGIN while atomic section(s) $levels are open.";
3883 throw new DBUnexpectedError( $this, $msg );
3884 } elseif ( !$this->trxAutomatic
) {
3885 $msg = "$fname: Explicit transaction already active (from {$this->trxFname}).";
3886 throw new DBUnexpectedError( $this, $msg );
3888 $msg = "$fname: Implicit transaction already active (from {$this->trxFname}).";
3889 throw new DBUnexpectedError( $this, $msg );
3891 } elseif ( $this->getFlag( self
::DBO_TRX
) && $mode !== self
::TRANSACTION_INTERNAL
) {
3892 $msg = "$fname: Implicit transaction expected (DBO_TRX set).";
3893 throw new DBUnexpectedError( $this, $msg );
3896 $this->assertHasConnectionHandle();
3898 $this->doBegin( $fname );
3899 $this->trxStatus
= self
::STATUS_TRX_OK
;
3900 $this->trxStatusIgnoredCause
= null;
3901 $this->trxAtomicCounter
= 0;
3902 $this->trxTimestamp
= microtime( true );
3903 $this->trxFname
= $fname;
3904 $this->trxDoneWrites
= false;
3905 $this->trxAutomaticAtomic
= false;
3906 $this->trxAtomicLevels
= [];
3907 $this->trxShortId
= sprintf( '%06x', mt_rand( 0, 0xffffff ) );
3908 $this->trxWriteDuration
= 0.0;
3909 $this->trxWriteQueryCount
= 0;
3910 $this->trxWriteAffectedRows
= 0;
3911 $this->trxWriteAdjDuration
= 0.0;
3912 $this->trxWriteAdjQueryCount
= 0;
3913 $this->trxWriteCallers
= [];
3914 // First SELECT after BEGIN will establish the snapshot in REPEATABLE-READ.
3915 // Get an estimate of the replication lag before any such queries.
3916 $this->trxReplicaLag
= null; // clear cached value first
3917 $this->trxReplicaLag
= $this->getApproximateLagStatus()['lag'];
3918 // T147697: make explicitTrxActive() return true until begin() finishes. This way, no
3919 // caller will think its OK to muck around with the transaction just because startAtomic()
3920 // has not yet completed (e.g. setting trxAtomicLevels).
3921 $this->trxAutomatic
= ( $mode === self
::TRANSACTION_INTERNAL
);
3925 * Issues the BEGIN command to the database server.
3927 * @see Database::begin()
3928 * @param string $fname
3930 protected function doBegin( $fname ) {
3931 $this->query( 'BEGIN', $fname );
3932 $this->trxLevel
= 1;
3935 final public function commit( $fname = __METHOD__
, $flush = self
::FLUSHING_ONE
) {
3936 static $modes = [ self
::FLUSHING_ONE
, self
::FLUSHING_ALL_PEERS
, self
::FLUSHING_INTERNAL
];
3937 if ( !in_array( $flush, $modes, true ) ) {
3938 throw new DBUnexpectedError( $this, "$fname: invalid flush parameter '$flush'." );
3941 if ( $this->trxLevel
&& $this->trxAtomicLevels
) {
3942 // There are still atomic sections open; this cannot be ignored
3943 $levels = $this->flatAtomicSectionList();
3944 throw new DBUnexpectedError(
3946 "$fname: Got COMMIT while atomic sections $levels are still open."
3950 if ( $flush === self
::FLUSHING_INTERNAL ||
$flush === self
::FLUSHING_ALL_PEERS
) {
3951 if ( !$this->trxLevel
) {
3952 return; // nothing to do
3953 } elseif ( !$this->trxAutomatic
) {
3954 throw new DBUnexpectedError(
3956 "$fname: Flushing an explicit transaction, getting out of sync."
3960 if ( !$this->trxLevel
) {
3961 $this->queryLogger
->error(
3962 "$fname: No transaction to commit, something got out of sync." );
3963 return; // nothing to do
3964 } elseif ( $this->trxAutomatic
) {
3965 throw new DBUnexpectedError(
3967 "$fname: Expected mass commit of all peer transactions (DBO_TRX set)."
3972 $this->assertHasConnectionHandle();
3974 $this->runOnTransactionPreCommitCallbacks();
3976 $writeTime = $this->pendingWriteQueryDuration( self
::ESTIMATE_DB_APPLY
);
3977 $this->doCommit( $fname );
3978 $this->trxStatus
= self
::STATUS_TRX_NONE
;
3980 if ( $this->trxDoneWrites
) {
3981 $this->lastWriteTime
= microtime( true );
3982 $this->trxProfiler
->transactionWritingOut(
3984 $this->getDomainID(),
3987 $this->trxWriteAffectedRows
3991 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
3992 if ( $flush !== self
::FLUSHING_ALL_PEERS
) {
3993 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_COMMIT
);
3994 $this->runTransactionListenerCallbacks( self
::TRIGGER_COMMIT
);
3999 * Issues the COMMIT command to the database server.
4001 * @see Database::commit()
4002 * @param string $fname
4004 protected function doCommit( $fname ) {
4005 if ( $this->trxLevel
) {
4006 $this->query( 'COMMIT', $fname );
4007 $this->trxLevel
= 0;
4011 final public function rollback( $fname = __METHOD__
, $flush = '' ) {
4012 $trxActive = $this->trxLevel
;
4014 if ( $flush !== self
::FLUSHING_INTERNAL
&& $flush !== self
::FLUSHING_ALL_PEERS
) {
4015 if ( $this->getFlag( self
::DBO_TRX
) ) {
4016 throw new DBUnexpectedError(
4018 "$fname: Expected mass rollback of all peer transactions (DBO_TRX set)."
4024 $this->assertHasConnectionHandle();
4026 $this->doRollback( $fname );
4027 $this->trxStatus
= self
::STATUS_TRX_NONE
;
4028 $this->trxAtomicLevels
= [];
4029 // Estimate the RTT via a query now that trxStatus is OK
4030 $writeTime = $this->pingAndCalculateLastTrxApplyTime();
4032 if ( $this->trxDoneWrites
) {
4033 $this->trxProfiler
->transactionWritingOut(
4035 $this->getDomainID(),
4038 $this->trxWriteAffectedRows
4043 // Clear any commit-dependant callbacks. They might even be present
4044 // only due to transaction rounds, with no SQL transaction being active
4045 $this->trxIdleCallbacks
= [];
4046 $this->trxPreCommitCallbacks
= [];
4048 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
4049 if ( $trxActive && $flush !== self
::FLUSHING_ALL_PEERS
) {
4051 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
4052 } catch ( Exception
$e ) {
4053 // already logged; finish and let LoadBalancer move on during mass-rollback
4056 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
4057 } catch ( Exception
$e ) {
4058 // already logged; let LoadBalancer move on during mass-rollback
4061 $this->affectedRowCount
= 0; // for the sake of consistency
4066 * Issues the ROLLBACK command to the database server.
4068 * @see Database::rollback()
4069 * @param string $fname
4071 protected function doRollback( $fname ) {
4072 if ( $this->trxLevel
) {
4073 # Disconnects cause rollback anyway, so ignore those errors
4074 $ignoreErrors = true;
4075 $this->query( 'ROLLBACK', $fname, $ignoreErrors );
4076 $this->trxLevel
= 0;
4080 public function flushSnapshot( $fname = __METHOD__
) {
4081 if ( $this->writesOrCallbacksPending() ||
$this->explicitTrxActive() ) {
4082 // This only flushes transactions to clear snapshots, not to write data
4083 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4084 throw new DBUnexpectedError(
4086 "$fname: Cannot flush snapshot because writes are pending ($fnames)."
4090 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4093 public function explicitTrxActive() {
4094 return $this->trxLevel
&& ( $this->trxAtomicLevels ||
!$this->trxAutomatic
);
4097 public function duplicateTableStructure(
4098 $oldName, $newName, $temporary = false, $fname = __METHOD__
4100 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4103 public function listTables( $prefix = null, $fname = __METHOD__
) {
4104 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4107 public function listViews( $prefix = null, $fname = __METHOD__
) {
4108 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4111 public function timestamp( $ts = 0 ) {
4112 $t = new ConvertibleTimestamp( $ts );
4113 // Let errors bubble up to avoid putting garbage in the DB
4114 return $t->getTimestamp( TS_MW
);
4117 public function timestampOrNull( $ts = null ) {
4118 if ( is_null( $ts ) ) {
4121 return $this->timestamp( $ts );
4125 public function affectedRows() {
4126 return ( $this->affectedRowCount
=== null )
4127 ?
$this->fetchAffectedRowCount() // default to driver value
4128 : $this->affectedRowCount
;
4132 * @return int Number of retrieved rows according to the driver
4134 abstract protected function fetchAffectedRowCount();
4137 * Take the result from a query, and wrap it in a ResultWrapper if
4138 * necessary. Boolean values are passed through as is, to indicate success
4139 * of write queries or failure.
4141 * Once upon a time, Database::query() returned a bare MySQL result
4142 * resource, and it was necessary to call this function to convert it to
4143 * a wrapper. Nowadays, raw database objects are never exposed to external
4144 * callers, so this is unnecessary in external code.
4146 * @param bool|ResultWrapper|resource $result
4147 * @return bool|ResultWrapper
4149 protected function resultObject( $result ) {
4152 } elseif ( $result instanceof ResultWrapper
) {
4154 } elseif ( $result === true ) {
4155 // Successful write query
4158 return new ResultWrapper( $this, $result );
4162 public function ping( &$rtt = null ) {
4163 // Avoid hitting the server if it was hit recently
4164 if ( $this->isOpen() && ( microtime( true ) - $this->lastPing
) < self
::PING_TTL
) {
4165 if ( !func_num_args() ||
$this->rttEstimate
> 0 ) {
4166 $rtt = $this->rttEstimate
;
4167 return true; // don't care about $rtt
4171 // This will reconnect if possible or return false if not
4172 $this->clearFlag( self
::DBO_TRX
, self
::REMEMBER_PRIOR
);
4173 $ok = ( $this->query( self
::PING_QUERY
, __METHOD__
, true ) !== false );
4174 $this->restoreFlags( self
::RESTORE_PRIOR
);
4177 $rtt = $this->rttEstimate
;
4184 * Close any existing (dead) database connection and open a new connection
4186 * @param string $fname
4187 * @return bool True if new connection is opened successfully, false if error
4189 protected function replaceLostConnection( $fname ) {
4190 $this->closeConnection();
4191 $this->opened
= false;
4192 $this->conn
= false;
4194 $this->handleSessionLossPreconnect();
4203 $this->tablePrefix()
4205 $this->lastPing
= microtime( true );
4208 $this->connLogger
->warning(
4209 $fname . ': lost connection to {dbserver}; reconnected',
4211 'dbserver' => $this->getServer(),
4212 'trace' => ( new RuntimeException() )->getTraceAsString()
4215 } catch ( DBConnectionError
$e ) {
4218 $this->connLogger
->error(
4219 $fname . ': lost connection to {dbserver} permanently',
4220 [ 'dbserver' => $this->getServer() ]
4224 $this->handleSessionLossPostconnect();
4229 public function getSessionLagStatus() {
4230 return $this->getRecordedTransactionLagStatus() ?
: $this->getApproximateLagStatus();
4234 * Get the replica DB lag when the current transaction started
4236 * This is useful when transactions might use snapshot isolation
4237 * (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data
4238 * is this lag plus transaction duration. If they don't, it is still
4239 * safe to be pessimistic. This returns null if there is no transaction.
4241 * This returns null if the lag status for this transaction was not yet recorded.
4243 * @return array|null ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)
4246 final protected function getRecordedTransactionLagStatus() {
4247 return ( $this->trxLevel
&& $this->trxReplicaLag
!== null )
4248 ?
[ 'lag' => $this->trxReplicaLag
, 'since' => $this->trxTimestamp() ]
4253 * Get a replica DB lag estimate for this server
4255 * @return array ('lag': seconds or false on error, 'since': UNIX timestamp of estimate)
4258 protected function getApproximateLagStatus() {
4260 'lag' => $this->getLBInfo( 'replica' ) ?
$this->getLag() : 0,
4261 'since' => microtime( true )
4266 * Merge the result of getSessionLagStatus() for several DBs
4267 * using the most pessimistic values to estimate the lag of
4268 * any data derived from them in combination
4270 * This is information is useful for caching modules
4272 * @see WANObjectCache::set()
4273 * @see WANObjectCache::getWithSetCallback()
4275 * @param IDatabase $db1
4276 * @param IDatabase|null $db2 [optional]
4277 * @return array Map of values:
4278 * - lag: highest lag of any of the DBs or false on error (e.g. replication stopped)
4279 * - since: oldest UNIX timestamp of any of the DB lag estimates
4280 * - pending: whether any of the DBs have uncommitted changes
4284 public static function getCacheSetOptions( IDatabase
$db1, IDatabase
$db2 = null ) {
4285 $res = [ 'lag' => 0, 'since' => INF
, 'pending' => false ];
4286 foreach ( func_get_args() as $db ) {
4287 /** @var IDatabase $db */
4288 $status = $db->getSessionLagStatus();
4289 if ( $status['lag'] === false ) {
4290 $res['lag'] = false;
4291 } elseif ( $res['lag'] !== false ) {
4292 $res['lag'] = max( $res['lag'], $status['lag'] );
4294 $res['since'] = min( $res['since'], $status['since'] );
4295 $res['pending'] = $res['pending'] ?
: $db->writesPending();
4301 public function getLag() {
4305 public function maxListLen() {
4309 public function encodeBlob( $b ) {
4313 public function decodeBlob( $b ) {
4314 if ( $b instanceof Blob
) {
4320 public function setSessionOptions( array $options ) {
4323 public function sourceFile(
4325 callable
$lineCallback = null,
4326 callable
$resultCallback = null,
4328 callable
$inputCallback = null
4330 Wikimedia\
suppressWarnings();
4331 $fp = fopen( $filename, 'r' );
4332 Wikimedia\restoreWarnings
();
4334 if ( $fp === false ) {
4335 throw new RuntimeException( "Could not open \"{$filename}\".\n" );
4339 $fname = __METHOD__
. "( $filename )";
4343 $error = $this->sourceStream(
4344 $fp, $lineCallback, $resultCallback, $fname, $inputCallback );
4345 } catch ( Exception
$e ) {
4355 public function setSchemaVars( $vars ) {
4356 $this->schemaVars
= $vars;
4359 public function sourceStream(
4361 callable
$lineCallback = null,
4362 callable
$resultCallback = null,
4363 $fname = __METHOD__
,
4364 callable
$inputCallback = null
4366 $delimiterReset = new ScopedCallback(
4367 function ( $delimiter ) {
4368 $this->delimiter
= $delimiter;
4370 [ $this->delimiter
]
4374 while ( !feof( $fp ) ) {
4375 if ( $lineCallback ) {
4376 call_user_func( $lineCallback );
4379 $line = trim( fgets( $fp ) );
4381 if ( $line == '' ) {
4385 if ( $line[0] == '-' && $line[1] == '-' ) {
4393 $done = $this->streamStatementEnd( $cmd, $line );
4397 if ( $done ||
feof( $fp ) ) {
4398 $cmd = $this->replaceVars( $cmd );
4400 if ( $inputCallback ) {
4401 $callbackResult = $inputCallback( $cmd );
4403 if ( is_string( $callbackResult ) ||
!$callbackResult ) {
4404 $cmd = $callbackResult;
4409 $res = $this->query( $cmd, $fname );
4411 if ( $resultCallback ) {
4412 $resultCallback( $res, $this );
4415 if ( $res === false ) {
4416 $err = $this->lastError();
4418 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
4425 ScopedCallback
::consume( $delimiterReset );
4430 * Called by sourceStream() to check if we've reached a statement end
4432 * @param string &$sql SQL assembled so far
4433 * @param string &$newLine New line about to be added to $sql
4434 * @return bool Whether $newLine contains end of the statement
4436 public function streamStatementEnd( &$sql, &$newLine ) {
4437 if ( $this->delimiter
) {
4439 $newLine = preg_replace(
4440 '/' . preg_quote( $this->delimiter
, '/' ) . '$/', '', $newLine );
4441 if ( $newLine != $prev ) {
4450 * Database independent variable replacement. Replaces a set of variables
4451 * in an SQL statement with their contents as given by $this->getSchemaVars().
4453 * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables.
4455 * - '{$var}' should be used for text and is passed through the database's
4457 * - `{$var}` should be used for identifiers (e.g. table and database names).
4458 * It is passed through the database's addIdentifierQuotes method which
4459 * can be overridden if the database uses something other than backticks.
4460 * - / *_* / or / *$wgDBprefix* / passes the name that follows through the
4461 * database's tableName method.
4462 * - / *i* / passes the name that follows through the database's indexName method.
4463 * - In all other cases, / *$var* / is left unencoded. Except for table options,
4464 * its use should be avoided. In 1.24 and older, string encoding was applied.
4466 * @param string $ins SQL statement to replace variables in
4467 * @return string The new SQL statement with variables replaced
4469 protected function replaceVars( $ins ) {
4470 $vars = $this->getSchemaVars();
4471 return preg_replace_callback(
4473 /\* (\$wgDBprefix|[_i]) \*/ (\w*) | # 1-2. tableName, indexName
4474 \'\{\$ (\w+) }\' | # 3. addQuotes
4475 `\{\$ (\w+) }` | # 4. addIdentifierQuotes
4476 /\*\$ (\w+) \*/ # 5. leave unencoded
4478 function ( $m ) use ( $vars ) {
4479 // Note: Because of <https://bugs.php.net/bug.php?id=51881>,
4480 // check for both nonexistent keys *and* the empty string.
4481 if ( isset( $m[1] ) && $m[1] !== '' ) {
4482 if ( $m[1] === 'i' ) {
4483 return $this->indexName( $m[2] );
4485 return $this->tableName( $m[2] );
4487 } elseif ( isset( $m[3] ) && $m[3] !== '' && array_key_exists( $m[3], $vars ) ) {
4488 return $this->addQuotes( $vars[$m[3]] );
4489 } elseif ( isset( $m[4] ) && $m[4] !== '' && array_key_exists( $m[4], $vars ) ) {
4490 return $this->addIdentifierQuotes( $vars[$m[4]] );
4491 } elseif ( isset( $m[5] ) && $m[5] !== '' && array_key_exists( $m[5], $vars ) ) {
4492 return $vars[$m[5]];
4502 * Get schema variables. If none have been set via setSchemaVars(), then
4503 * use some defaults from the current object.
4507 protected function getSchemaVars() {
4508 if ( $this->schemaVars
) {
4509 return $this->schemaVars
;
4511 return $this->getDefaultSchemaVars();
4516 * Get schema variables to use if none have been set via setSchemaVars().
4518 * Override this in derived classes to provide variables for tables.sql
4519 * and SQL patch files.
4523 protected function getDefaultSchemaVars() {
4527 public function lockIsFree( $lockName, $method ) {
4528 // RDBMs methods for checking named locks may or may not count this thread itself.
4529 // In MySQL, IS_FREE_LOCK() returns 0 if the thread already has the lock. This is
4530 // the behavior choosen by the interface for this method.
4531 return !isset( $this->namedLocksHeld
[$lockName] );
4534 public function lock( $lockName, $method, $timeout = 5 ) {
4535 $this->namedLocksHeld
[$lockName] = 1;
4540 public function unlock( $lockName, $method ) {
4541 unset( $this->namedLocksHeld
[$lockName] );
4546 public function getScopedLockAndFlush( $lockKey, $fname, $timeout ) {
4547 if ( $this->writesOrCallbacksPending() ) {
4548 // This only flushes transactions to clear snapshots, not to write data
4549 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4550 throw new DBUnexpectedError(
4552 "$fname: Cannot flush pre-lock snapshot because writes are pending ($fnames)."
4556 if ( !$this->lock( $lockKey, $fname, $timeout ) ) {
4560 $unlocker = new ScopedCallback( function () use ( $lockKey, $fname ) {
4561 if ( $this->trxLevel() ) {
4562 // There is a good chance an exception was thrown, causing any early return
4563 // from the caller. Let any error handler get a chance to issue rollback().
4564 // If there isn't one, let the error bubble up and trigger server-side rollback.
4565 $this->onTransactionResolution(
4566 function () use ( $lockKey, $fname ) {
4567 $this->unlock( $lockKey, $fname );
4572 $this->unlock( $lockKey, $fname );
4576 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4581 public function namedLocksEnqueue() {
4585 public function tableLocksHaveTransactionScope() {
4589 final public function lockTables( array $read, array $write, $method ) {
4590 if ( $this->writesOrCallbacksPending() ) {
4591 throw new DBUnexpectedError( $this, "Transaction writes or callbacks still pending." );
4594 if ( $this->tableLocksHaveTransactionScope() ) {
4595 $this->startAtomic( $method );
4598 return $this->doLockTables( $read, $write, $method );
4602 * Helper function for lockTables() that handles the actual table locking
4604 * @param array $read Array of tables to lock for read access
4605 * @param array $write Array of tables to lock for write access
4606 * @param string $method Name of caller
4609 protected function doLockTables( array $read, array $write, $method ) {
4613 final public function unlockTables( $method ) {
4614 if ( $this->tableLocksHaveTransactionScope() ) {
4615 $this->endAtomic( $method );
4617 return true; // locks released on COMMIT/ROLLBACK
4620 return $this->doUnlockTables( $method );
4624 * Helper function for unlockTables() that handles the actual table unlocking
4626 * @param string $method Name of caller
4629 protected function doUnlockTables( $method ) {
4635 * @param string $tableName
4636 * @param string $fName
4637 * @return bool|ResultWrapper
4640 public function dropTable( $tableName, $fName = __METHOD__
) {
4641 if ( !$this->tableExists( $tableName, $fName ) ) {
4644 $sql = "DROP TABLE " . $this->tableName( $tableName ) . " CASCADE";
4646 return $this->query( $sql, $fName );
4649 public function getInfinity() {
4653 public function encodeExpiry( $expiry ) {
4654 return ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() )
4655 ?
$this->getInfinity()
4656 : $this->timestamp( $expiry );
4659 public function decodeExpiry( $expiry, $format = TS_MW
) {
4660 if ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() ) {
4664 return ConvertibleTimestamp
::convert( $format, $expiry );
4667 public function setBigSelects( $value = true ) {
4671 public function isReadOnly() {
4672 return ( $this->getReadOnlyReason() !== false );
4676 * @return string|bool Reason this DB is read-only or false if it is not
4678 protected function getReadOnlyReason() {
4679 $reason = $this->getLBInfo( 'readOnlyReason' );
4681 return is_string( $reason ) ?
$reason : false;
4684 public function setTableAliases( array $aliases ) {
4685 $this->tableAliases
= $aliases;
4688 public function setIndexAliases( array $aliases ) {
4689 $this->indexAliases
= $aliases;
4693 * Get the underlying binding connection handle
4695 * Makes sure the connection resource is set (disconnects and ping() failure can unset it).
4696 * This catches broken callers than catch and ignore disconnection exceptions.
4697 * Unlike checking isOpen(), this is safe to call inside of open().
4700 * @throws DBUnexpectedError
4703 protected function getBindingHandle() {
4704 if ( !$this->conn
) {
4705 throw new DBUnexpectedError(
4707 'DB connection was already closed or the connection dropped.'
4718 public function __toString() {
4719 return (string)$this->conn
;
4723 * Make sure that copies do not share the same client binding handle
4724 * @throws DBConnectionError
4726 public function __clone() {
4727 $this->connLogger
->warning(
4728 "Cloning " . static::class . " is not recommended; forking connection:\n" .
4729 ( new RuntimeException() )->getTraceAsString()
4732 if ( $this->isOpen() ) {
4733 // Open a new connection resource without messing with the old one
4734 $this->opened
= false;
4735 $this->conn
= false;
4736 $this->trxEndCallbacks
= []; // don't copy
4737 $this->handleSessionLossPreconnect(); // no trx or locks anymore
4744 $this->tablePrefix()
4746 $this->lastPing
= microtime( true );
4751 * Called by serialize. Throw an exception when DB connection is serialized.
4752 * This causes problems on some database engines because the connection is
4753 * not restored on unserialize.
4755 public function __sleep() {
4756 throw new RuntimeException( 'Database serialization may cause problems, since ' .
4757 'the connection is not restored on wakeup.' );
4761 * Run a few simple sanity checks and close dangling connections
4763 public function __destruct() {
4764 if ( $this->trxLevel
&& $this->trxDoneWrites
) {
4765 trigger_error( "Uncommitted DB writes (transaction from {$this->trxFname})." );
4768 $danglingWriters = $this->pendingWriteAndCallbackCallers();
4769 if ( $danglingWriters ) {
4770 $fnames = implode( ', ', $danglingWriters );
4771 trigger_error( "DB transaction writes or callbacks still pending ($fnames)." );
4774 if ( $this->conn
) {
4775 // Avoid connection leaks for sanity. Normally, resources close at script completion.
4776 // The connection might already be closed in zend/hhvm by now, so suppress warnings.
4777 Wikimedia\
suppressWarnings();
4778 $this->closeConnection();
4779 Wikimedia\restoreWarnings
();
4780 $this->conn
= false;
4781 $this->opened
= false;
4787 * @deprecated since 1.28
4789 class_alias( Database
::class, 'DatabaseBase' );
4792 * @deprecated since 1.29
4794 class_alias( Database
::class, 'Database' );