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
;
33 use Wikimedia\AtEase\AtEase
;
37 use InvalidArgumentException
;
38 use UnexpectedValueException
;
44 * Relational database abstraction object
49 abstract class Database
implements IDatabase
, IMaintainableDatabase
, LoggerAwareInterface
{
50 /** @var string Server that this instance is currently connected to */
52 /** @var string User that this instance is currently connected under the name of */
54 /** @var string Password used to establish the current connection */
56 /** @var array[] Map of (table => (dbname, schema, prefix) map) */
57 protected $tableAliases = [];
58 /** @var string[] Map of (index alias => index) */
59 protected $indexAliases = [];
60 /** @var bool Whether this PHP instance is for a CLI script */
62 /** @var string Agent name for query profiling */
64 /** @var int Bitfield of class DBO_* constants */
66 /** @var array LoadBalancer tracking information */
67 protected $lbInfo = [];
68 /** @var array|bool Variables use for schema element placeholders */
69 protected $schemaVars = false;
70 /** @var array Parameters used by initConnection() to establish a connection */
71 protected $connectionParams = [];
72 /** @var array SQL variables values to use for all new connections */
73 protected $connectionVariables = [];
74 /** @var string Current SQL query delimiter */
75 protected $delimiter = ';';
76 /** @var string|bool|null Stashed value of html_errors INI setting */
77 protected $htmlErrors;
78 /** @var int Row batch size to use for emulated INSERT SELECT queries */
79 protected $nonNativeInsertSelectBatchSize = 10000;
81 /** @var BagOStuff APC cache */
83 /** @var LoggerInterface */
84 protected $connLogger;
85 /** @var LoggerInterface */
86 protected $queryLogger;
87 /** @var callable Error logging callback */
88 protected $errorLogger;
89 /** @var callable Deprecation logging callback */
90 protected $deprecationLogger;
91 /** @var callable|null */
93 /** @var TransactionProfiler */
94 protected $trxProfiler;
95 /** @var DatabaseDomain */
96 protected $currentDomain;
97 /** @var object|resource|null Database connection */
100 /** @var IDatabase|null Lazy handle to the master DB this server replicates from */
101 private $lazyMasterHandle;
103 /** @var array Map of (name => 1) for locks obtained via lock() */
104 protected $sessionNamedLocks = [];
105 /** @var array Map of (table name => 1) for TEMPORARY tables */
106 protected $sessionTempTables = [];
108 /** @var string ID of the active transaction or the empty string otherwise */
109 protected $trxShortId = '';
110 /** @var int Transaction status */
111 protected $trxStatus = self
::STATUS_TRX_NONE
;
112 /** @var Exception|null The last error that caused the status to become STATUS_TRX_ERROR */
113 protected $trxStatusCause;
114 /** @var array|null Error details of the last statement-only rollback */
115 private $trxStatusIgnoredCause;
116 /** @var float|null UNIX timestamp at the time of BEGIN for the last transaction */
117 private $trxTimestamp = null;
118 /** @var float Replication lag estimate at the time of BEGIN for the last transaction */
119 private $trxReplicaLag = null;
120 /** @var string Name of the function that start the last transaction */
121 private $trxFname = null;
122 /** @var bool Whether possible write queries were done in the last transaction started */
123 private $trxDoneWrites = false;
124 /** @var bool Whether the current transaction was started implicitly due to DBO_TRX */
125 private $trxAutomatic = false;
126 /** @var int Counter for atomic savepoint identifiers (reset with each transaction) */
127 private $trxAtomicCounter = 0;
128 /** @var array List of (name, unique ID, savepoint ID) for each active atomic section level */
129 private $trxAtomicLevels = [];
130 /** @var bool Whether the current transaction was started implicitly by startAtomic() */
131 private $trxAutomaticAtomic = false;
132 /** @var string[] Write query callers of the current transaction */
133 private $trxWriteCallers = [];
134 /** @var float Seconds spent in write queries for the current transaction */
135 private $trxWriteDuration = 0.0;
136 /** @var int Number of write queries for the current transaction */
137 private $trxWriteQueryCount = 0;
138 /** @var int Number of rows affected by write queries for the current transaction */
139 private $trxWriteAffectedRows = 0;
140 /** @var float Like trxWriteQueryCount but excludes lock-bound, easy to replicate, queries */
141 private $trxWriteAdjDuration = 0.0;
142 /** @var int Number of write queries counted in trxWriteAdjDuration */
143 private $trxWriteAdjQueryCount = 0;
144 /** @var array[] List of (callable, method name, atomic section id) */
145 private $trxIdleCallbacks = [];
146 /** @var array[] List of (callable, method name, atomic section id) */
147 private $trxPreCommitCallbacks = [];
148 /** @var array[] List of (callable, method name, atomic section id) */
149 private $trxEndCallbacks = [];
150 /** @var array[] List of (callable, method name, atomic section id) */
151 private $trxSectionCancelCallbacks = [];
152 /** @var callable[] Map of (name => callable) */
153 private $trxRecurringCallbacks = [];
154 /** @var bool Whether to suppress triggering of transaction end callbacks */
155 private $trxEndCallbacksSuppressed = false;
157 /** @var int[] Prior flags member variable values */
158 private $priorFlags = [];
160 /** @var integer|null Rows affected by the last query to query() or its CRUD wrappers */
161 protected $affectedRowCount;
163 /** @var float UNIX timestamp */
164 private $lastPing = 0.0;
165 /** @var string The last SQL query attempted */
166 private $lastQuery = '';
167 /** @var float|bool UNIX timestamp of last write query */
168 private $lastWriteTime = false;
169 /** @var string|bool */
170 private $lastPhpError = false;
171 /** @var float Query rount trip time estimate */
172 private $lastRoundTripEstimate = 0.0;
174 /** @var string Lock granularity is on the level of the entire database */
175 const ATTR_DB_LEVEL_LOCKING
= 'db-level-locking';
176 /** @var string The SCHEMA keyword refers to a grouping of tables in a database */
177 const ATTR_SCHEMAS_AS_TABLE_GROUPS
= 'supports-schemas';
179 /** @var int New Database instance will not be connected yet when returned */
180 const NEW_UNCONNECTED
= 0;
181 /** @var int New Database instance will already be connected when returned */
182 const NEW_CONNECTED
= 1;
184 /** @var int Transaction is in a error state requiring a full or savepoint rollback */
185 const STATUS_TRX_ERROR
= 1;
186 /** @var int Transaction is active and in a normal state */
187 const STATUS_TRX_OK
= 2;
188 /** @var int No transaction is active */
189 const STATUS_TRX_NONE
= 3;
191 /** @var string Idiom used when a cancelable atomic section started the transaction */
192 private static $NOT_APPLICABLE = 'n/a';
193 /** @var string Prefix to the atomic section counter used to make savepoint IDs */
194 private static $SAVEPOINT_PREFIX = 'wikimedia_rdbms_atomic';
196 /** @var int Writes to this temporary table do not affect lastDoneWrites() */
197 private static $TEMP_NORMAL = 1;
198 /** @var int Writes to this temporary table effect lastDoneWrites() */
199 private static $TEMP_PSEUDO_PERMANENT = 2;
201 /** @var int Number of times to re-try an operation in case of deadlock */
202 private static $DEADLOCK_TRIES = 4;
203 /** @var int Minimum time to wait before retry, in microseconds */
204 private static $DEADLOCK_DELAY_MIN = 500000;
205 /** @var int Maximum time to wait before retry */
206 private static $DEADLOCK_DELAY_MAX = 1500000;
208 /** @var int How long before it is worth doing a dummy query to test the connection */
209 private static $PING_TTL = 1.0;
210 /** @var string Dummy SQL query */
211 private static $PING_QUERY = 'SELECT 1 AS ping';
213 /** @var float Guess of how many seconds it takes to replicate a small insert */
214 private static $TINY_WRITE_SEC = 0.010;
215 /** @var float Consider a write slow if it took more than this many seconds */
216 private static $SLOW_WRITE_SEC = 0.500;
217 /** @var float Assume an insert of this many rows or less should be fast to replicate */
218 private static $SMALL_WRITE_ROWS = 100;
221 * @note exceptions for missing libraries/drivers should be thrown in initConnection()
222 * @param array $params Parameters passed from Database::factory()
224 protected function __construct( array $params ) {
225 foreach ( [ 'host', 'user', 'password', 'dbname', 'schema', 'tablePrefix' ] as $name ) {
226 $this->connectionParams
[$name] = $params[$name];
229 $this->cliMode
= $params['cliMode'];
230 // Agent name is added to SQL queries in a comment, so make sure it can't break out
231 $this->agent
= str_replace( '/', '-', $params['agent'] );
233 $this->flags
= $params['flags'];
234 if ( $this->flags
& self
::DBO_DEFAULT
) {
235 if ( $this->cliMode
) {
236 $this->flags
&= ~self
::DBO_TRX
;
238 $this->flags |
= self
::DBO_TRX
;
241 // Disregard deprecated DBO_IGNORE flag (T189999)
242 $this->flags
&= ~self
::DBO_IGNORE
;
244 $this->connectionVariables
= $params['variables'];
246 $this->srvCache
= $params['srvCache'] ??
new HashBagOStuff();
248 $this->profiler
= is_callable( $params['profiler'] ) ?
$params['profiler'] : null;
249 $this->trxProfiler
= $params['trxProfiler'];
250 $this->connLogger
= $params['connLogger'];
251 $this->queryLogger
= $params['queryLogger'];
252 $this->errorLogger
= $params['errorLogger'];
253 $this->deprecationLogger
= $params['deprecationLogger'];
255 if ( isset( $params['nonNativeInsertSelectBatchSize'] ) ) {
256 $this->nonNativeInsertSelectBatchSize
= $params['nonNativeInsertSelectBatchSize'];
259 // Set initial dummy domain until open() sets the final DB/prefix
260 $this->currentDomain
= new DatabaseDomain(
261 $params['dbname'] != '' ?
$params['dbname'] : null,
262 $params['schema'] != '' ?
$params['schema'] : null,
263 $params['tablePrefix']
268 * Initialize the connection to the database over the wire (or to local files)
270 * @throws LogicException
271 * @throws InvalidArgumentException
272 * @throws DBConnectionError
275 final public function initConnection() {
276 if ( $this->isOpen() ) {
277 throw new LogicException( __METHOD__
. ': already connected' );
279 // Establish the connection
280 $this->doInitConnection();
284 * Actually connect to the database over the wire (or to local files)
286 * @throws InvalidArgumentException
287 * @throws DBConnectionError
290 protected function doInitConnection() {
291 if ( strlen( $this->connectionParams
['user'] ) ) {
293 $this->connectionParams
['host'],
294 $this->connectionParams
['user'],
295 $this->connectionParams
['password'],
296 $this->connectionParams
['dbname'],
297 $this->connectionParams
['schema'],
298 $this->connectionParams
['tablePrefix']
301 throw new InvalidArgumentException( "No database user provided" );
306 * Open a new connection to the database (closing any existing one)
308 * @param string|null $server Database server host
309 * @param string|null $user Database user name
310 * @param string|null $password Database user password
311 * @param string|null $dbName Database name
312 * @param string|null $schema Database schema name
313 * @param string $tablePrefix Table prefix
314 * @throws DBConnectionError
316 abstract protected function open( $server, $user, $password, $dbName, $schema, $tablePrefix );
319 * Construct a Database subclass instance given a database type and parameters
321 * This also connects to the database immediately upon object construction
323 * @param string $type A possible DB type (sqlite, mysql, postgres,...)
324 * @param array $params Parameter map with keys:
325 * - host : The hostname of the DB server
326 * - user : The name of the database user the client operates under
327 * - password : The password for the database user
328 * - dbname : The name of the database to use where queries do not specify one.
329 * The database must exist or an error might be thrown. Setting this to the empty string
330 * will avoid any such errors and make the handle have no implicit database scope. This is
331 * useful for queries like SHOW STATUS, CREATE DATABASE, or DROP DATABASE. Note that a
332 * "database" in Postgres is rougly equivalent to an entire MySQL server. This the domain
333 * in which user names and such are defined, e.g. users are database-specific in Postgres.
334 * - schema : The database schema to use (if supported). A "schema" in Postgres is roughly
335 * equivalent to a "database" in MySQL. Note that MySQL and SQLite do not use schemas.
336 * - tablePrefix : Optional table prefix that is implicitly added on to all table names
337 * recognized in queries. This can be used in place of schemas for handle site farms.
338 * - flags : Optional bitfield of DBO_* constants that define connection, protocol,
339 * buffering, and transaction behavior. It is STRONGLY adviced to leave the DBO_DEFAULT
340 * flag in place UNLESS this this database simply acts as a key/value store.
341 * - driver: Optional name of a specific DB client driver. For MySQL, there is only the
342 * 'mysqli' driver; the old one 'mysql' has been removed.
343 * - variables: Optional map of session variables to set after connecting. This can be
344 * used to adjust lock timeouts or encoding modes and the like.
345 * - connLogger: Optional PSR-3 logger interface instance.
346 * - queryLogger: Optional PSR-3 logger interface instance.
347 * - profiler : Optional callback that takes a section name argument and returns
348 * a ScopedCallback instance that ends the profile section in its destructor.
349 * These will be called in query(), using a simplified version of the SQL that
350 * also includes the agent as a SQL comment.
351 * - trxProfiler: Optional TransactionProfiler instance.
352 * - errorLogger: Optional callback that takes an Exception and logs it.
353 * - deprecationLogger: Optional callback that takes a string and logs it.
354 * - cliMode: Whether to consider the execution context that of a CLI script.
355 * - agent: Optional name used to identify the end-user in query profiling/logging.
356 * - srvCache: Optional BagOStuff instance to an APC-style cache.
357 * - nonNativeInsertSelectBatchSize: Optional batch size for non-native INSERT SELECT emulation.
358 * @param int $connect One of the class constants (NEW_CONNECTED, NEW_UNCONNECTED) [optional]
359 * @return Database|null If the database driver or extension cannot be found
360 * @throws InvalidArgumentException If the database driver or extension cannot be found
363 final public static function factory( $type, $params = [], $connect = self
::NEW_CONNECTED
) {
364 $class = self
::getClass( $type, $params['driver'] ??
null );
366 if ( class_exists( $class ) && is_subclass_of( $class, IDatabase
::class ) ) {
376 'cliMode' => ( PHP_SAPI
=== 'cli' || PHP_SAPI
=== 'phpdbg' ),
377 'agent' => basename( $_SERVER['SCRIPT_NAME'] ) . '@' . gethostname()
380 $normalizedParams = [
382 'host' => strlen( $params['host'] ) ?
$params['host'] : null,
383 'user' => strlen( $params['user'] ) ?
$params['user'] : null,
384 'password' => is_string( $params['password'] ) ?
$params['password'] : null,
385 'dbname' => strlen( $params['dbname'] ) ?
$params['dbname'] : null,
386 'schema' => strlen( $params['schema'] ) ?
$params['schema'] : null,
387 'tablePrefix' => (string)$params['tablePrefix'],
388 'flags' => (int)$params['flags'],
389 'variables' => $params['variables'],
390 'cliMode' => (bool)$params['cliMode'],
391 'agent' => (string)$params['agent'],
392 // Objects and callbacks
393 'profiler' => $params['profiler'] ??
null,
394 'trxProfiler' => $params['trxProfiler'] ??
new TransactionProfiler(),
395 'connLogger' => $params['connLogger'] ??
new NullLogger(),
396 'queryLogger' => $params['queryLogger'] ??
new NullLogger(),
397 'errorLogger' => $params['errorLogger'] ??
function ( Exception
$e ) {
398 trigger_error( get_class( $e ) . ': ' . $e->getMessage(), E_USER_WARNING
);
400 'deprecationLogger' => $params['deprecationLogger'] ??
function ( $msg ) {
401 trigger_error( $msg, E_USER_DEPRECATED
);
405 /** @var Database $conn */
406 $conn = new $class( $normalizedParams );
407 if ( $connect === self
::NEW_CONNECTED
) {
408 $conn->initConnection();
418 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
419 * @param string|null $driver Optional name of a specific DB client driver
420 * @return array Map of (Database::ATTR_* constant => value) for all such constants
421 * @throws InvalidArgumentException
424 final public static function attributesFromType( $dbType, $driver = null ) {
426 self
::ATTR_DB_LEVEL_LOCKING
=> false,
427 self
::ATTR_SCHEMAS_AS_TABLE_GROUPS
=> false
430 $class = self
::getClass( $dbType, $driver );
432 return call_user_func( [ $class, 'getAttributes' ] ) +
$defaults;
436 * @param string $dbType A possible DB type (sqlite, mysql, postgres,...)
437 * @param string|null $driver Optional name of a specific DB client driver
438 * @return string Database subclass name to use
439 * @throws InvalidArgumentException
441 private static function getClass( $dbType, $driver = null ) {
442 // For database types with built-in support, the below maps type to IDatabase
443 // implementations. For types with multipe driver implementations (PHP extensions),
444 // an array can be used, keyed by extension name. In case of an array, the
445 // optional 'driver' parameter can be used to force a specific driver. Otherwise,
446 // we auto-detect the first available driver. For types without built-in support,
447 // an class named "Database<Type>" us used, eg. DatabaseFoo for type 'foo'.
448 static $builtinTypes = [
449 'mssql' => DatabaseMssql
::class,
450 'mysql' => [ 'mysqli' => DatabaseMysqli
::class ],
451 'sqlite' => DatabaseSqlite
::class,
452 'postgres' => DatabasePostgres
::class,
455 $dbType = strtolower( $dbType );
458 if ( isset( $builtinTypes[$dbType] ) ) {
459 $possibleDrivers = $builtinTypes[$dbType];
460 if ( is_string( $possibleDrivers ) ) {
461 $class = $possibleDrivers;
462 } elseif ( (string)$driver !== '' ) {
463 if ( !isset( $possibleDrivers[$driver] ) ) {
464 throw new InvalidArgumentException( __METHOD__
.
465 " type '$dbType' does not support driver '{$driver}'" );
468 $class = $possibleDrivers[$driver];
470 foreach ( $possibleDrivers as $posDriver => $possibleClass ) {
471 if ( extension_loaded( $posDriver ) ) {
472 $class = $possibleClass;
478 $class = 'Database' . ucfirst( $dbType );
481 if ( $class === false ) {
482 throw new InvalidArgumentException( __METHOD__
.
483 " no viable database extension found for type '$dbType'" );
490 * @return array Map of (Database::ATTR_* constant => value
493 protected static function getAttributes() {
498 * Set the PSR-3 logger interface to use for query logging. (The logger
499 * interfaces for connection logging and error logging can be set with the
502 * @param LoggerInterface $logger
504 public function setLogger( LoggerInterface
$logger ) {
505 $this->queryLogger
= $logger;
508 public function getServerInfo() {
509 return $this->getServerVersion();
512 public function bufferResults( $buffer = null ) {
513 $res = !$this->getFlag( self
::DBO_NOBUFFER
);
514 if ( $buffer !== null ) {
516 ?
$this->clearFlag( self
::DBO_NOBUFFER
)
517 : $this->setFlag( self
::DBO_NOBUFFER
);
523 final public function trxLevel() {
524 return ( $this->trxShortId
!= '' ) ?
1 : 0;
527 public function trxTimestamp() {
528 return $this->trxLevel() ?
$this->trxTimestamp
: null;
532 * @return int One of the STATUS_TRX_* class constants
535 public function trxStatus() {
536 return $this->trxStatus
;
539 public function tablePrefix( $prefix = null ) {
540 $old = $this->currentDomain
->getTablePrefix();
541 if ( $prefix !== null ) {
542 $this->currentDomain
= new DatabaseDomain(
543 $this->currentDomain
->getDatabase(),
544 $this->currentDomain
->getSchema(),
552 public function dbSchema( $schema = null ) {
553 if ( strlen( $schema ) && $this->getDBname() === null ) {
554 throw new DBUnexpectedError( $this, "Cannot set schema to '$schema'; no database set" );
557 $old = $this->currentDomain
->getSchema();
558 if ( $schema !== null ) {
559 $this->currentDomain
= new DatabaseDomain(
560 $this->currentDomain
->getDatabase(),
561 // DatabaseDomain uses null for unspecified schemas
562 strlen( $schema ) ?
$schema : null,
563 $this->currentDomain
->getTablePrefix()
571 * @return string Schema to use to qualify relations in queries
573 protected function relationSchemaQualifier() {
574 return $this->dbSchema();
577 public function getLBInfo( $name = null ) {
578 if ( is_null( $name ) ) {
579 return $this->lbInfo
;
582 if ( array_key_exists( $name, $this->lbInfo
) ) {
583 return $this->lbInfo
[$name];
589 public function setLBInfo( $nameOrArray, $value = null ) {
590 if ( is_array( $nameOrArray ) ) {
591 $this->lbInfo
= $nameOrArray;
592 } elseif ( is_string( $nameOrArray ) ) {
593 if ( $value !== null ) {
594 $this->lbInfo
[$nameOrArray] = $value;
596 unset( $this->lbInfo
[$nameOrArray] );
599 throw new InvalidArgumentException( "Got non-string key" );
603 public function setLazyMasterHandle( IDatabase
$conn ) {
604 $this->lazyMasterHandle
= $conn;
608 * @return IDatabase|null
609 * @see setLazyMasterHandle()
612 protected function getLazyMasterHandle() {
613 return $this->lazyMasterHandle
;
616 public function implicitGroupby() {
620 public function implicitOrderby() {
624 public function lastQuery() {
625 return $this->lastQuery
;
628 public function doneWrites() {
629 return (bool)$this->lastWriteTime
;
632 public function lastDoneWrites() {
633 return $this->lastWriteTime ?
: false;
636 public function writesPending() {
637 return $this->trxLevel() && $this->trxDoneWrites
;
640 public function writesOrCallbacksPending() {
641 return $this->trxLevel() && (
642 $this->trxDoneWrites ||
643 $this->trxIdleCallbacks ||
644 $this->trxPreCommitCallbacks ||
645 $this->trxEndCallbacks ||
646 $this->trxSectionCancelCallbacks
650 public function preCommitCallbacksPending() {
651 return $this->trxLevel() && $this->trxPreCommitCallbacks
;
655 * @return string|null
657 final protected function getTransactionRoundId() {
658 // If transaction round participation is enabled, see if one is active
659 if ( $this->getFlag( self
::DBO_TRX
) ) {
660 $id = $this->getLBInfo( 'trxRoundId' );
662 return is_string( $id ) ?
$id : null;
668 public function pendingWriteQueryDuration( $type = self
::ESTIMATE_TOTAL
) {
669 if ( !$this->trxLevel() ) {
671 } elseif ( !$this->trxDoneWrites
) {
676 case self
::ESTIMATE_DB_APPLY
:
677 return $this->pingAndCalculateLastTrxApplyTime();
678 default: // everything
679 return $this->trxWriteDuration
;
684 * @return float Time to apply writes to replicas based on trxWrite* fields
686 private function pingAndCalculateLastTrxApplyTime() {
689 $rttAdjTotal = $this->trxWriteAdjQueryCount
* $rtt;
690 $applyTime = max( $this->trxWriteAdjDuration
- $rttAdjTotal, 0 );
691 // For omitted queries, make them count as something at least
692 $omitted = $this->trxWriteQueryCount
- $this->trxWriteAdjQueryCount
;
693 $applyTime +
= self
::$TINY_WRITE_SEC * $omitted;
698 public function pendingWriteCallers() {
699 return $this->trxLevel() ?
$this->trxWriteCallers
: [];
702 public function pendingWriteRowsAffected() {
703 return $this->trxWriteAffectedRows
;
707 * List the methods that have write queries or callbacks for the current transaction
709 * This method should not be used outside of Database/LoadBalancer
714 public function pendingWriteAndCallbackCallers() {
715 $fnames = $this->pendingWriteCallers();
717 $this->trxIdleCallbacks
,
718 $this->trxPreCommitCallbacks
,
719 $this->trxEndCallbacks
,
720 $this->trxSectionCancelCallbacks
722 foreach ( $callbacks as $callback ) {
723 $fnames[] = $callback[1];
733 private function flatAtomicSectionList() {
734 return array_reduce( $this->trxAtomicLevels
, function ( $accum, $v ) {
735 return $accum === null ?
$v[0] : "$accum, " . $v[0];
739 public function isOpen() {
740 return (bool)$this->conn
;
743 public function setFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
744 if ( ( $flag & self
::DBO_IGNORE
) ) {
745 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed" );
748 if ( $remember === self
::REMEMBER_PRIOR
) {
749 array_push( $this->priorFlags
, $this->flags
);
751 $this->flags |
= $flag;
754 public function clearFlag( $flag, $remember = self
::REMEMBER_NOTHING
) {
755 if ( ( $flag & self
::DBO_IGNORE
) ) {
756 throw new UnexpectedValueException( "Modifying DBO_IGNORE is not allowed" );
759 if ( $remember === self
::REMEMBER_PRIOR
) {
760 array_push( $this->priorFlags
, $this->flags
);
762 $this->flags
&= ~
$flag;
765 public function restoreFlags( $state = self
::RESTORE_PRIOR
) {
766 if ( !$this->priorFlags
) {
770 if ( $state === self
::RESTORE_INITIAL
) {
771 $this->flags
= reset( $this->priorFlags
);
772 $this->priorFlags
= [];
774 $this->flags
= array_pop( $this->priorFlags
);
778 public function getFlag( $flag ) {
779 return (bool)( $this->flags
& $flag );
783 * @param string $name Class field name
785 * @deprecated Since 1.28
787 public function getProperty( $name ) {
791 public function getDomainID() {
792 return $this->currentDomain
->getId();
795 final public function getWikiID() {
796 return $this->getDomainID();
800 * Get information about an index into an object
801 * @param string $table Table name
802 * @param string $index Index name
803 * @param string $fname Calling function name
804 * @return mixed Database-specific index description class or false if the index does not exist
806 abstract function indexInfo( $table, $index, $fname = __METHOD__
);
809 * Wrapper for addslashes()
811 * @param string $s String to be slashed.
812 * @return string Slashed string.
814 abstract function strencode( $s );
817 * Set a custom error handler for logging errors during database connection
819 protected function installErrorHandler() {
820 $this->lastPhpError
= false;
821 $this->htmlErrors
= ini_set( 'html_errors', '0' );
822 set_error_handler( [ $this, 'connectionErrorLogger' ] );
826 * Restore the previous error handler and return the last PHP error for this DB
828 * @return bool|string
830 protected function restoreErrorHandler() {
831 restore_error_handler();
832 if ( $this->htmlErrors
!== false ) {
833 ini_set( 'html_errors', $this->htmlErrors
);
836 return $this->getLastPHPError();
840 * @return string|bool Last PHP error for this DB (typically connection errors)
842 protected function getLastPHPError() {
843 if ( $this->lastPhpError
) {
844 $error = preg_replace( '!\[<a.*</a>\]!', '', $this->lastPhpError
);
845 $error = preg_replace( '!^.*?:\s?(.*)$!', '$1', $error );
854 * Error handler for logging errors during database connection
855 * This method should not be used outside of Database classes
858 * @param string $errstr
860 public function connectionErrorLogger( $errno, $errstr ) {
861 $this->lastPhpError
= $errstr;
865 * Create a log context to pass to PSR-3 logger functions.
867 * @param array $extras Additional data to add to context
870 protected function getLogContext( array $extras = [] ) {
873 'db_server' => $this->server
,
874 'db_name' => $this->getDBname(),
875 'db_user' => $this->user
,
881 final public function close() {
882 $exception = null; // error to throw after disconnecting
884 $wasOpen = (bool)$this->conn
;
885 // This should mostly do nothing if the connection is already closed
887 // Roll back any dangling transaction first
888 if ( $this->trxLevel() ) {
889 if ( $this->trxAtomicLevels
) {
890 // Cannot let incomplete atomic sections be committed
891 $levels = $this->flatAtomicSectionList();
892 $exception = new DBUnexpectedError(
894 __METHOD__
. ": atomic sections $levels are still open"
896 } elseif ( $this->trxAutomatic
) {
897 // Only the connection manager can commit non-empty DBO_TRX transactions
898 // (empty ones we can silently roll back)
899 if ( $this->writesOrCallbacksPending() ) {
900 $exception = new DBUnexpectedError(
903 ": mass commit/rollback of peer transaction required (DBO_TRX set)"
907 // Manual transactions should have been committed or rolled
908 // back, even if empty.
909 $exception = new DBUnexpectedError(
911 __METHOD__
. ": transaction is still open (from {$this->trxFname})"
915 if ( $this->trxEndCallbacksSuppressed
) {
916 $exception = $exception ?
: new DBUnexpectedError(
918 __METHOD__
. ': callbacks are suppressed; cannot properly commit'
922 // Rollback the changes and run any callbacks as needed
923 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
926 // Close the actual connection in the binding handle
927 $closed = $this->closeConnection();
929 $closed = true; // already closed; nothing to do
934 // Throw any unexpected errors after having disconnected
935 if ( $exception instanceof Exception
) {
939 // Note that various subclasses call close() at the start of open(), which itself is
940 // called by replaceLostConnection(). In that case, just because onTransactionResolution()
941 // callbacks are pending does not mean that an exception should be thrown. Rather, they
942 // will be executed after the reconnection step.
944 // Sanity check that no callbacks are dangling
945 $fnames = $this->pendingWriteAndCallbackCallers();
947 throw new RuntimeException(
948 "Transaction callbacks are still pending: " . implode( ', ', $fnames )
957 * Make sure there is an open connection handle (alive or not) as a sanity check
959 * This guards against fatal errors to the binding handle not being defined
960 * in cases where open() was never called or close() was already called
962 * @throws DBUnexpectedError
964 final protected function assertHasConnectionHandle() {
965 if ( !$this->isOpen() ) {
966 throw new DBUnexpectedError( $this, "DB connection was already closed" );
971 * Make sure that this server is not marked as a replica nor read-only as a sanity check
973 * @throws DBReadOnlyRoleError
974 * @throws DBReadOnlyError
976 protected function assertIsWritableMaster() {
977 if ( $this->getLBInfo( 'replica' ) === true ) {
978 throw new DBReadOnlyRoleError(
980 'Write operations are not allowed on replica database connections'
983 $reason = $this->getReadOnlyReason();
984 if ( $reason !== false ) {
985 throw new DBReadOnlyError( $this, "Database is read-only: $reason" );
990 * Closes underlying database connection
992 * @return bool Whether connection was closed successfully
994 abstract protected function closeConnection();
997 * Run a query and return a DBMS-dependent wrapper or boolean
999 * This is meant to handle the basic command of actually sending a query to the
1000 * server via the driver. No implicit transaction, reconnection, nor retry logic
1001 * should happen here. The higher level query() method is designed to handle those
1002 * sorts of concerns. This method should not trigger such higher level methods.
1004 * The lastError() and lastErrno() methods should meaningfully reflect what error,
1005 * if any, occured during the last call to this method. Methods like executeQuery(),
1006 * query(), select(), insert(), update(), delete(), and upsert() implement their calls
1007 * to doQuery() such that an immediately subsequent call to lastError()/lastErrno()
1008 * meaningfully reflects any error that occured during that public query method call.
1010 * For SELECT queries, this returns either:
1011 * - a) A driver-specific value/resource, only on success. This can be iterated
1012 * over by calling fetchObject()/fetchRow() until there are no more rows.
1013 * Alternatively, the result can be passed to resultObject() to obtain an
1014 * IResultWrapper instance which can then be iterated over via "foreach".
1015 * - b) False, on any query failure
1017 * For non-SELECT queries, this returns either:
1018 * - a) A driver-specific value/resource, only on success
1019 * - b) True, only on success (e.g. no meaningful result other than "OK")
1020 * - c) False, on any query failure
1022 * @param string $sql SQL query
1023 * @return mixed|bool An object, resource, or true on success; false on failure
1025 abstract protected function doQuery( $sql );
1028 * Determine whether a query writes to the DB. When in doubt, this returns true.
1032 * - Subsequent web requests should not need to wait for replication from
1033 * the master position seen by this web request, unless this request made
1034 * changes to the master. This is handled by ChronologyProtector by checking
1035 * doneWrites() at the end of the request. doneWrites() returns true if any
1036 * query set lastWriteTime; which query() does based on isWriteQuery().
1038 * - Reject write queries to replica DBs, in query().
1040 * @param string $sql
1043 protected function isWriteQuery( $sql ) {
1044 // BEGIN and COMMIT queries are considered read queries here.
1045 // Database backends and drivers (MySQL, MariaDB, php-mysqli) generally
1046 // treat these as write queries, in that their results have "affected rows"
1047 // as meta data as from writes, instead of "num rows" as from reads.
1048 // But, we treat them as read queries because when reading data (from
1049 // either replica or master) we use transactions to enable repeatable-read
1050 // snapshots, which ensures we get consistent results from the same snapshot
1051 // for all queries within a request. Use cases:
1052 // - Treating these as writes would trigger ChronologyProtector (see method doc).
1053 // - We use this method to reject writes to replicas, but we need to allow
1054 // use of transactions on replicas for read snapshots. This is fine given
1055 // that transactions by themselves don't make changes, only actual writes
1056 // within the transaction matter, which we still detect.
1058 '/^(?:SELECT|BEGIN|ROLLBACK|COMMIT|SAVEPOINT|RELEASE|SET|SHOW|EXPLAIN|USE|\(SELECT)\b/i',
1064 * @param string $sql
1065 * @return string|null
1067 protected function getQueryVerb( $sql ) {
1068 return preg_match( '/^\s*([a-z]+)/i', $sql, $m ) ?
strtoupper( $m[1] ) : null;
1072 * Determine whether a SQL statement is sensitive to isolation level.
1074 * A SQL statement is considered transactable if its result could vary
1075 * depending on the transaction isolation level. Operational commands
1076 * such as 'SET' and 'SHOW' are not considered to be transactable.
1078 * Main purpose: Used by query() to decide whether to begin a transaction
1079 * before the current query (in DBO_TRX mode, on by default).
1081 * @param string $sql
1084 protected function isTransactableQuery( $sql ) {
1086 $this->getQueryVerb( $sql ),
1087 [ 'BEGIN', 'ROLLBACK', 'COMMIT', 'SET', 'SHOW', 'CREATE', 'ALTER', 'USE', 'SHOW' ],
1093 * @param string $sql A SQL query
1094 * @param bool $pseudoPermanent Treat any table from CREATE TEMPORARY as pseudo-permanent
1095 * @return array A n-tuple of:
1096 * - int|null: A self::TEMP_* constant for temp table operations or null otherwise
1097 * - string|null: The name of the new temporary table $sql creates, or null
1098 * - string|null: The name of the temporary table that $sql drops, or null
1100 protected function getTempWrites( $sql, $pseudoPermanent ) {
1101 static $qt = '[`"\']?(\w+)[`"\']?'; // quoted table
1104 '/^CREATE\s+TEMPORARY\s+TABLE\s+(?:IF\s+NOT\s+EXISTS\s+)?' . $qt . '/i',
1108 $type = $pseudoPermanent ? self
::$TEMP_PSEUDO_PERMANENT : self
::$TEMP_NORMAL;
1110 return [ $type, $matches[1], null ];
1111 } elseif ( preg_match(
1112 '/^DROP\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?' . $qt . '/i',
1116 return [ $this->sessionTempTables
[$matches[1]] ??
null, null, $matches[1] ];
1117 } elseif ( preg_match(
1118 '/^TRUNCATE\s+(?:TEMPORARY\s+)?TABLE\s+(?:IF\s+EXISTS\s+)?' . $qt . '/i',
1122 return [ $this->sessionTempTables
[$matches[1]] ??
null, null, null ];
1123 } elseif ( preg_match(
1124 '/^(?:(?:INSERT|REPLACE)\s+(?:\w+\s+)?INTO|UPDATE|DELETE\s+FROM)\s+' . $qt . '/i',
1128 return [ $this->sessionTempTables
[$matches[1]] ??
null, null, null ];
1131 return [ null, null, null ];
1135 * @param IResultWrapper|bool $ret
1136 * @param int|null $tmpType TEMP_NORMAL or TEMP_PSEUDO_PERMANENT
1137 * @param string|null $tmpNew Name of created temp table
1138 * @param string|null $tmpDel Name of dropped temp table
1140 protected function registerTempWrites( $ret, $tmpType, $tmpNew, $tmpDel ) {
1141 if ( $ret !== false ) {
1142 if ( $tmpNew !== null ) {
1143 $this->sessionTempTables
[$tmpNew] = $tmpType;
1145 if ( $tmpDel !== null ) {
1146 unset( $this->sessionTempTables
[$tmpDel] );
1151 public function query( $sql, $fname = __METHOD__
, $flags = 0 ) {
1152 $flags = (int)$flags; // b/c; this field used to be a bool
1153 // Sanity check that the SQL query is appropriate in the current context and is
1154 // allowed for an outside caller (e.g. does not break transaction/session tracking).
1155 $this->assertQueryIsCurrentlyAllowed( $sql, $fname );
1157 // Send the query to the server and fetch any corresponding errors
1158 list( $ret, $err, $errno, $unignorable ) = $this->executeQuery( $sql, $fname, $flags );
1159 if ( $ret === false ) {
1160 $ignoreErrors = $this->hasFlags( $flags, self
::QUERY_SILENCE_ERRORS
);
1161 // Throw an error unless both the ignore flag was set and a rollback is not needed
1162 $this->reportQueryError( $err, $errno, $sql, $fname, $ignoreErrors && !$unignorable );
1165 return $this->resultObject( $ret );
1169 * Execute a query, retrying it if there is a recoverable connection loss
1171 * This is similar to query() except:
1172 * - It does not prevent all non-ROLLBACK queries if there is a corrupted transaction
1173 * - It does not disallow raw queries that are supposed to use dedicated IDatabase methods
1174 * - It does not throw exceptions for common error cases
1176 * This is meant for internal use with Database subclasses.
1178 * @param string $sql Original SQL query
1179 * @param string $fname Name of the calling function
1180 * @param int $flags Bitfield of class QUERY_* constants
1181 * @return array An n-tuple of:
1182 * - mixed|bool: An object, resource, or true on success; false on failure
1183 * - string: The result of calling lastError()
1184 * - int: The result of calling lastErrno()
1185 * - bool: Whether a rollback is needed to allow future non-rollback queries
1186 * @throws DBUnexpectedError
1188 final protected function executeQuery( $sql, $fname, $flags ) {
1189 $this->assertHasConnectionHandle();
1191 $priorTransaction = $this->trxLevel();
1193 if ( $this->isWriteQuery( $sql ) ) {
1194 // In theory, non-persistent writes are allowed in read-only mode, but due to things
1195 // like https://bugs.mysql.com/bug.php?id=33669 that might not work anyway...
1196 $this->assertIsWritableMaster();
1197 // Do not treat temporary table writes as "meaningful writes" since they are only
1198 // visible to one session and are not permanent. Profile them as reads. Integration
1199 // tests can override this behavior via $flags.
1200 $pseudoPermanent = $this->hasFlags( $flags, self
::QUERY_PSEUDO_PERMANENT
);
1201 list( $tmpType, $tmpNew, $tmpDel ) = $this->getTempWrites( $sql, $pseudoPermanent );
1202 $isPermWrite = ( $tmpType !== self
::$TEMP_NORMAL );
1203 // DBConnRef uses QUERY_REPLICA_ROLE to enforce the replica role for raw SQL queries
1204 if ( $isPermWrite && $this->hasFlags( $flags, self
::QUERY_REPLICA_ROLE
) ) {
1205 throw new DBReadOnlyRoleError( $this, "Cannot write; target role is DB_REPLICA" );
1208 // No permanent writes in this query
1209 $isPermWrite = false;
1210 // No temporary tables written to either
1211 list( $tmpType, $tmpNew, $tmpDel ) = [ null, null, null ];
1214 // Add trace comment to the begin of the sql string, right after the operator.
1215 // Or, for one-word queries (like "BEGIN" or COMMIT") add it to the end (T44598)
1216 $commentedSql = preg_replace( '/\s|$/', " /* $fname {$this->agent} */ ", $sql, 1 );
1218 // Send the query to the server and fetch any corresponding errors.
1219 // This also doubles as a "ping" to see if the connection was dropped.
1220 list( $ret, $err, $errno, $recoverableSR, $recoverableCL, $reconnected ) =
1221 $this->executeQueryAttempt( $sql, $commentedSql, $isPermWrite, $fname, $flags );
1223 // Check if the query failed due to a recoverable connection loss
1224 $allowRetry = !$this->hasFlags( $flags, self
::QUERY_NO_RETRY
);
1225 if ( $ret === false && $recoverableCL && $reconnected && $allowRetry ) {
1226 // Silently resend the query to the server since it is safe and possible
1227 list( $ret, $err, $errno, $recoverableSR, $recoverableCL ) =
1228 $this->executeQueryAttempt( $sql, $commentedSql, $isPermWrite, $fname, $flags );
1231 // Register creation and dropping of temporary tables
1232 $this->registerTempWrites( $ret, $tmpType, $tmpNew, $tmpDel );
1234 $corruptedTrx = false;
1236 if ( $ret === false ) {
1237 if ( $priorTransaction ) {
1238 if ( $recoverableSR ) {
1239 # We're ignoring an error that caused just the current query to be aborted.
1240 # But log the cause so we can log a deprecation notice if a caller actually
1242 $this->trxStatusIgnoredCause
= [ $err, $errno, $fname ];
1243 } elseif ( !$recoverableCL ) {
1244 # Either the query was aborted or all queries after BEGIN where aborted.
1245 # In the first case, the only options going forward are (a) ROLLBACK, or
1246 # (b) ROLLBACK TO SAVEPOINT (if one was set). If the later case, the only
1247 # option is ROLLBACK, since the snapshots would have been released.
1248 $corruptedTrx = true; // cannot recover
1249 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
1250 $this->trxStatusCause
=
1251 $this->getQueryExceptionAndLog( $err, $errno, $sql, $fname );
1252 $this->trxStatusIgnoredCause
= null;
1257 return [ $ret, $err, $errno, $corruptedTrx ];
1261 * Wrapper for doQuery() that handles DBO_TRX, profiling, logging, affected row count
1262 * tracking, and reconnects (without retry) on query failure due to connection loss
1264 * @param string $sql Original SQL query
1265 * @param string $commentedSql SQL query with debugging/trace comment
1266 * @param bool $isPermWrite Whether the query is a (non-temporary table) write
1267 * @param string $fname Name of the calling function
1268 * @param int $flags Bitfield of class QUERY_* constants
1269 * @return array An n-tuple of:
1270 * - mixed|bool: An object, resource, or true on success; false on failure
1271 * - string: The result of calling lastError()
1272 * - int: The result of calling lastErrno()
1273 * - bool: Whether a statement rollback error occured
1274 * - bool: Whether a disconnect *both* happened *and* was recoverable
1275 * - bool: Whether a reconnection attempt was *both* made *and* succeeded
1276 * @throws DBUnexpectedError
1278 private function executeQueryAttempt( $sql, $commentedSql, $isPermWrite, $fname, $flags ) {
1279 $priorWritesPending = $this->writesOrCallbacksPending();
1281 if ( ( $flags & self
::QUERY_IGNORE_DBO_TRX
) == 0 ) {
1282 $this->beginIfImplied( $sql, $fname );
1285 // Keep track of whether the transaction has write queries pending
1286 if ( $isPermWrite ) {
1287 $this->lastWriteTime
= microtime( true );
1288 if ( $this->trxLevel() && !$this->trxDoneWrites
) {
1289 $this->trxDoneWrites
= true;
1290 $this->trxProfiler
->transactionWritingIn(
1291 $this->server
, $this->getDomainID(), $this->trxShortId
);
1295 $prefix = !is_null( $this->getLBInfo( 'master' ) ) ?
'query-m: ' : 'query: ';
1296 $generalizedSql = new GeneralizedSql( $sql, $this->trxShortId
, $prefix );
1298 $startTime = microtime( true );
1299 $ps = $this->profiler
1300 ?
( $this->profiler
)( $generalizedSql->stringify() )
1302 $this->affectedRowCount
= null;
1303 $this->lastQuery
= $sql;
1304 $ret = $this->doQuery( $commentedSql );
1305 $lastError = $this->lastError();
1306 $lastErrno = $this->lastErrno();
1308 $this->affectedRowCount
= $this->affectedRows();
1309 unset( $ps ); // profile out (if set)
1310 $queryRuntime = max( microtime( true ) - $startTime, 0.0 );
1312 $recoverableSR = false; // recoverable statement rollback?
1313 $recoverableCL = false; // recoverable connection loss?
1314 $reconnected = false; // reconnection both attempted and succeeded?
1316 if ( $ret !== false ) {
1317 $this->lastPing
= $startTime;
1318 if ( $isPermWrite && $this->trxLevel() ) {
1319 $this->updateTrxWriteQueryTime( $sql, $queryRuntime, $this->affectedRows() );
1320 $this->trxWriteCallers
[] = $fname;
1322 } elseif ( $this->wasConnectionError( $lastErrno ) ) {
1323 # Check if no meaningful session state was lost
1324 $recoverableCL = $this->canRecoverFromDisconnect( $sql, $priorWritesPending );
1325 # Update session state tracking and try to restore the connection
1326 $reconnected = $this->replaceLostConnection( __METHOD__
);
1328 # Check if only the last query was rolled back
1329 $recoverableSR = $this->wasKnownStatementRollbackError();
1332 if ( $sql === self
::$PING_QUERY ) {
1333 $this->lastRoundTripEstimate
= $queryRuntime;
1336 $this->trxProfiler
->recordQueryCompletion(
1340 $isPermWrite ?
$this->affectedRows() : $this->numRows( $ret )
1343 // Avoid the overhead of logging calls unless debug mode is enabled
1344 if ( $this->getFlag( self
::DBO_DEBUG
) ) {
1345 $this->queryLogger
->debug(
1346 "{method} [{runtime}s]: $sql",
1349 'db_host' => $this->getServer(),
1350 'domain' => $this->getDomainID(),
1351 'runtime' => round( $queryRuntime, 3 )
1356 return [ $ret, $lastError, $lastErrno, $recoverableSR, $recoverableCL, $reconnected ];
1360 * Start an implicit transaction if DBO_TRX is enabled and no transaction is active
1362 * @param string $sql
1363 * @param string $fname
1365 private function beginIfImplied( $sql, $fname ) {
1367 !$this->trxLevel() &&
1368 $this->getFlag( self
::DBO_TRX
) &&
1369 $this->isTransactableQuery( $sql )
1371 $this->begin( __METHOD__
. " ($fname)", self
::TRANSACTION_INTERNAL
);
1372 $this->trxAutomatic
= true;
1377 * Update the estimated run-time of a query, not counting large row lock times
1379 * LoadBalancer can be set to rollback transactions that will create huge replication
1380 * lag. It bases this estimate off of pendingWriteQueryDuration(). Certain simple
1381 * queries, like inserting a row can take a long time due to row locking. This method
1382 * uses some simple heuristics to discount those cases.
1384 * @param string $sql A SQL write query
1385 * @param float $runtime Total runtime, including RTT
1386 * @param int $affected Affected row count
1388 private function updateTrxWriteQueryTime( $sql, $runtime, $affected ) {
1389 // Whether this is indicative of replica DB runtime (except for RBR or ws_repl)
1390 $indicativeOfReplicaRuntime = true;
1391 if ( $runtime > self
::$SLOW_WRITE_SEC ) {
1392 $verb = $this->getQueryVerb( $sql );
1393 // insert(), upsert(), replace() are fast unless bulky in size or blocked on locks
1394 if ( $verb === 'INSERT' ) {
1395 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::$SMALL_WRITE_ROWS;
1396 } elseif ( $verb === 'REPLACE' ) {
1397 $indicativeOfReplicaRuntime = $this->affectedRows() > self
::$SMALL_WRITE_ROWS / 2;
1401 $this->trxWriteDuration +
= $runtime;
1402 $this->trxWriteQueryCount +
= 1;
1403 $this->trxWriteAffectedRows +
= $affected;
1404 if ( $indicativeOfReplicaRuntime ) {
1405 $this->trxWriteAdjDuration +
= $runtime;
1406 $this->trxWriteAdjQueryCount +
= 1;
1411 * Error out if the DB is not in a valid state for a query via query()
1413 * @param string $sql
1414 * @param string $fname
1415 * @throws DBTransactionStateError
1417 private function assertQueryIsCurrentlyAllowed( $sql, $fname ) {
1418 $verb = $this->getQueryVerb( $sql );
1419 if ( $verb === 'USE' ) {
1420 throw new DBUnexpectedError( $this, "Got USE query; use selectDomain() instead" );
1423 if ( $verb === 'ROLLBACK' ) { // transaction/savepoint
1427 if ( $this->trxStatus
< self
::STATUS_TRX_OK
) {
1428 throw new DBTransactionStateError(
1430 "Cannot execute query from $fname while transaction status is ERROR",
1432 $this->trxStatusCause
1434 } elseif ( $this->trxStatus
=== self
::STATUS_TRX_OK
&& $this->trxStatusIgnoredCause
) {
1435 list( $iLastError, $iLastErrno, $iFname ) = $this->trxStatusIgnoredCause
;
1436 call_user_func( $this->deprecationLogger
,
1437 "Caller from $fname ignored an error originally raised from $iFname: " .
1438 "[$iLastErrno] $iLastError"
1440 $this->trxStatusIgnoredCause
= null;
1444 public function assertNoOpenTransactions() {
1445 if ( $this->explicitTrxActive() ) {
1446 throw new DBTransactionError(
1448 "Explicit transaction still active. A caller may have caught an error. "
1449 . "Open transactions: " . $this->flatAtomicSectionList()
1455 * Determine whether it is safe to retry queries after a database connection is lost
1457 * @param string $sql SQL query
1458 * @param bool $priorWritesPending Whether there is a transaction open with
1459 * possible write queries or transaction pre-commit/idle callbacks
1460 * waiting on it to finish.
1461 * @return bool True if it is safe to retry the query, false otherwise
1463 private function canRecoverFromDisconnect( $sql, $priorWritesPending ) {
1464 # Transaction dropped; this can mean lost writes, or REPEATABLE-READ snapshots.
1465 # Dropped connections also mean that named locks are automatically released.
1466 # Only allow error suppression in autocommit mode or when the lost transaction
1467 # didn't matter anyway (aside from DBO_TRX snapshot loss).
1468 if ( $this->sessionNamedLocks
) {
1469 return false; // possible critical section violation
1470 } elseif ( $this->sessionTempTables
) {
1471 return false; // tables might be queried latter
1472 } elseif ( $sql === 'COMMIT' ) {
1473 return !$priorWritesPending; // nothing written anyway? (T127428)
1474 } elseif ( $sql === 'ROLLBACK' ) {
1475 return true; // transaction lost...which is also what was requested :)
1476 } elseif ( $this->explicitTrxActive() ) {
1477 return false; // don't drop atomocity and explicit snapshots
1478 } elseif ( $priorWritesPending ) {
1479 return false; // prior writes lost from implicit transaction
1486 * Clean things up after session (and thus transaction) loss before reconnect
1488 private function handleSessionLossPreconnect() {
1489 // Clean up tracking of session-level things...
1490 // https://dev.mysql.com/doc/refman/5.7/en/implicit-commit.html
1491 // https://www.postgresql.org/docs/9.2/static/sql-createtable.html (ignoring ON COMMIT)
1492 $this->sessionTempTables
= [];
1493 // https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1494 // https://www.postgresql.org/docs/9.4/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
1495 $this->sessionNamedLocks
= [];
1496 // Session loss implies transaction loss
1497 $oldTrxShortId = $this->consumeTrxShortId();
1498 $this->trxAtomicCounter
= 0;
1499 $this->trxIdleCallbacks
= []; // T67263; transaction already lost
1500 $this->trxPreCommitCallbacks
= []; // T67263; transaction already lost
1501 // @note: leave trxRecurringCallbacks in place
1502 if ( $this->trxDoneWrites
) {
1503 $this->trxProfiler
->transactionWritingOut(
1505 $this->getDomainID(),
1507 $this->pendingWriteQueryDuration( self
::ESTIMATE_TOTAL
),
1508 $this->trxWriteAffectedRows
1514 * Clean things up after session (and thus transaction) loss after reconnect
1516 private function handleSessionLossPostconnect() {
1518 // Handle callbacks in trxEndCallbacks, e.g. onTransactionResolution().
1519 // If callback suppression is set then the array will remain unhandled.
1520 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
1521 } catch ( Exception
$ex ) {
1522 // Already logged; move on...
1525 // Handle callbacks in trxRecurringCallbacks, e.g. setTransactionListener()
1526 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
1527 } catch ( Exception
$ex ) {
1528 // Already logged; move on...
1533 * Reset the transaction ID and return the old one
1535 * @return string The old transaction ID or the empty string if there wasn't one
1537 private function consumeTrxShortId() {
1538 $old = $this->trxShortId
;
1539 $this->trxShortId
= '';
1545 * Checks whether the cause of the error is detected to be a timeout.
1547 * It returns false by default, and not all engines support detecting this yet.
1548 * If this returns false, it will be treated as a generic query error.
1550 * @param string $error Error text
1551 * @param int $errno Error number
1554 protected function wasQueryTimeout( $error, $errno ) {
1559 * Report a query error. Log the error, and if neither the object ignore
1560 * flag nor the $ignoreErrors flag is set, throw a DBQueryError.
1562 * @param string $error
1564 * @param string $sql
1565 * @param string $fname
1566 * @param bool $ignore
1567 * @throws DBQueryError
1569 public function reportQueryError( $error, $errno, $sql, $fname, $ignore = false ) {
1571 $this->queryLogger
->debug( "SQL ERROR (ignored): $error" );
1573 $exception = $this->getQueryExceptionAndLog( $error, $errno, $sql, $fname );
1580 * @param string $error
1581 * @param string|int $errno
1582 * @param string $sql
1583 * @param string $fname
1586 private function getQueryExceptionAndLog( $error, $errno, $sql, $fname ) {
1587 $sql1line = mb_substr( str_replace( "\n", "\\n", $sql ), 0, 5 * 1024 );
1588 $this->queryLogger
->error(
1589 "{fname}\t{db_server}\t{errno}\t{error}\t{sql1line}",
1590 $this->getLogContext( [
1591 'method' => __METHOD__
,
1594 'sql1line' => $sql1line,
1596 'trace' => ( new RuntimeException() )->getTraceAsString()
1599 $this->queryLogger
->debug( "SQL ERROR: " . $error . "" );
1600 if ( $this->wasQueryTimeout( $error, $errno ) ) {
1601 $e = new DBQueryTimeoutError( $this, $error, $errno, $sql, $fname );
1602 } elseif ( $this->wasConnectionError( $errno ) ) {
1603 $e = new DBQueryDisconnectedError( $this, $error, $errno, $sql, $fname );
1605 $e = new DBQueryError( $this, $error, $errno, $sql, $fname );
1611 public function freeResult( $res ) {
1614 public function selectField(
1615 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1617 if ( $var === '*' ) { // sanity
1618 throw new DBUnexpectedError( $this, "Cannot use a * field: got '$var'" );
1621 if ( !is_array( $options ) ) {
1622 $options = [ $options ];
1625 $options['LIMIT'] = 1;
1627 $res = $this->select( $table, $var, $cond, $fname, $options, $join_conds );
1628 if ( $res === false ) {
1629 throw new DBUnexpectedError( $this, "Got false from select()" );
1632 $row = $this->fetchRow( $res );
1633 if ( $row === false ) {
1637 return reset( $row );
1640 public function selectFieldValues(
1641 $table, $var, $cond = '', $fname = __METHOD__
, $options = [], $join_conds = []
1643 if ( $var === '*' ) { // sanity
1644 throw new DBUnexpectedError( $this, "Cannot use a * field" );
1645 } elseif ( !is_string( $var ) ) { // sanity
1646 throw new DBUnexpectedError( $this, "Cannot use an array of fields" );
1649 if ( !is_array( $options ) ) {
1650 $options = [ $options ];
1653 $res = $this->select( $table, [ 'value' => $var ], $cond, $fname, $options, $join_conds );
1654 if ( $res === false ) {
1655 throw new DBUnexpectedError( $this, "Got false from select()" );
1659 foreach ( $res as $row ) {
1660 $values[] = $row->value
;
1667 * Returns an optional USE INDEX clause to go after the table, and a
1668 * string to go at the end of the query.
1670 * @param array $options Associative array of options to be turned into
1671 * an SQL query, valid keys are listed in the function.
1673 * @see Database::select()
1675 protected function makeSelectOptions( $options ) {
1676 $preLimitTail = $postLimitTail = '';
1681 foreach ( $options as $key => $option ) {
1682 if ( is_numeric( $key ) ) {
1683 $noKeyOptions[$option] = true;
1687 $preLimitTail .= $this->makeGroupByWithHaving( $options );
1689 $preLimitTail .= $this->makeOrderBy( $options );
1691 if ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
1692 $postLimitTail .= ' FOR UPDATE';
1695 if ( isset( $noKeyOptions['LOCK IN SHARE MODE'] ) ) {
1696 $postLimitTail .= ' LOCK IN SHARE MODE';
1699 if ( isset( $noKeyOptions['DISTINCT'] ) ||
isset( $noKeyOptions['DISTINCTROW'] ) ) {
1700 $startOpts .= 'DISTINCT';
1703 # Various MySQL extensions
1704 if ( isset( $noKeyOptions['STRAIGHT_JOIN'] ) ) {
1705 $startOpts .= ' /*! STRAIGHT_JOIN */';
1708 if ( isset( $noKeyOptions['HIGH_PRIORITY'] ) ) {
1709 $startOpts .= ' HIGH_PRIORITY';
1712 if ( isset( $noKeyOptions['SQL_BIG_RESULT'] ) ) {
1713 $startOpts .= ' SQL_BIG_RESULT';
1716 if ( isset( $noKeyOptions['SQL_BUFFER_RESULT'] ) ) {
1717 $startOpts .= ' SQL_BUFFER_RESULT';
1720 if ( isset( $noKeyOptions['SQL_SMALL_RESULT'] ) ) {
1721 $startOpts .= ' SQL_SMALL_RESULT';
1724 if ( isset( $noKeyOptions['SQL_CALC_FOUND_ROWS'] ) ) {
1725 $startOpts .= ' SQL_CALC_FOUND_ROWS';
1728 if ( isset( $noKeyOptions['SQL_CACHE'] ) ) {
1729 $startOpts .= ' SQL_CACHE';
1732 if ( isset( $noKeyOptions['SQL_NO_CACHE'] ) ) {
1733 $startOpts .= ' SQL_NO_CACHE';
1736 if ( isset( $options['USE INDEX'] ) && is_string( $options['USE INDEX'] ) ) {
1737 $useIndex = $this->useIndexClause( $options['USE INDEX'] );
1741 if ( isset( $options['IGNORE INDEX'] ) && is_string( $options['IGNORE INDEX'] ) ) {
1742 $ignoreIndex = $this->ignoreIndexClause( $options['IGNORE INDEX'] );
1747 return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
1751 * Returns an optional GROUP BY with an optional HAVING
1753 * @param array $options Associative array of options
1755 * @see Database::select()
1758 protected function makeGroupByWithHaving( $options ) {
1760 if ( isset( $options['GROUP BY'] ) ) {
1761 $gb = is_array( $options['GROUP BY'] )
1762 ?
implode( ',', $options['GROUP BY'] )
1763 : $options['GROUP BY'];
1764 $sql .= ' GROUP BY ' . $gb;
1766 if ( isset( $options['HAVING'] ) ) {
1767 $having = is_array( $options['HAVING'] )
1768 ?
$this->makeList( $options['HAVING'], self
::LIST_AND
)
1769 : $options['HAVING'];
1770 $sql .= ' HAVING ' . $having;
1777 * Returns an optional ORDER BY
1779 * @param array $options Associative array of options
1781 * @see Database::select()
1784 protected function makeOrderBy( $options ) {
1785 if ( isset( $options['ORDER BY'] ) ) {
1786 $ob = is_array( $options['ORDER BY'] )
1787 ?
implode( ',', $options['ORDER BY'] )
1788 : $options['ORDER BY'];
1790 return ' ORDER BY ' . $ob;
1796 public function select(
1797 $table, $vars, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1799 $sql = $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
1801 return $this->query( $sql, $fname );
1804 public function selectSQLText( $table, $vars, $conds = '', $fname = __METHOD__
,
1805 $options = [], $join_conds = []
1807 if ( is_array( $vars ) ) {
1808 $fields = implode( ',', $this->fieldNamesWithAlias( $vars ) );
1813 $options = (array)$options;
1814 $useIndexes = ( isset( $options['USE INDEX'] ) && is_array( $options['USE INDEX'] ) )
1815 ?
$options['USE INDEX']
1818 isset( $options['IGNORE INDEX'] ) &&
1819 is_array( $options['IGNORE INDEX'] )
1821 ?
$options['IGNORE INDEX']
1825 $this->selectOptionsIncludeLocking( $options ) &&
1826 $this->selectFieldsOrOptionsAggregate( $vars, $options )
1828 // Some DB types (postgres/oracle) disallow FOR UPDATE with aggregate
1829 // functions. Discourage use of such queries to encourage compatibility.
1831 $this->deprecationLogger
,
1832 __METHOD__
. ": aggregation used with a locking SELECT ($fname)"
1836 if ( is_array( $table ) ) {
1838 $this->tableNamesWithIndexClauseOrJOIN(
1839 $table, $useIndexes, $ignoreIndexes, $join_conds );
1840 } elseif ( $table != '' ) {
1842 $this->tableNamesWithIndexClauseOrJOIN(
1843 [ $table ], $useIndexes, $ignoreIndexes, [] );
1848 list( $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ) =
1849 $this->makeSelectOptions( $options );
1851 if ( is_array( $conds ) ) {
1852 $conds = $this->makeList( $conds, self
::LIST_AND
);
1855 if ( $conds === null ||
$conds === false ) {
1856 $this->queryLogger
->warning(
1860 . ' with incorrect parameters: $conds must be a string or an array'
1865 if ( $conds === '' ||
$conds === '*' ) {
1866 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex $preLimitTail";
1867 } elseif ( is_string( $conds ) ) {
1868 $sql = "SELECT $startOpts $fields $from $useIndex $ignoreIndex " .
1869 "WHERE $conds $preLimitTail";
1871 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
1874 if ( isset( $options['LIMIT'] ) ) {
1875 $sql = $this->limitResult( $sql, $options['LIMIT'],
1876 $options['OFFSET'] ??
false );
1878 $sql = "$sql $postLimitTail";
1880 if ( isset( $options['EXPLAIN'] ) ) {
1881 $sql = 'EXPLAIN ' . $sql;
1887 public function selectRow( $table, $vars, $conds, $fname = __METHOD__
,
1888 $options = [], $join_conds = []
1890 $options = (array)$options;
1891 $options['LIMIT'] = 1;
1893 $res = $this->select( $table, $vars, $conds, $fname, $options, $join_conds );
1894 if ( $res === false ) {
1895 throw new DBUnexpectedError( $this, "Got false from select()" );
1898 if ( !$this->numRows( $res ) ) {
1902 return $this->fetchObject( $res );
1905 public function estimateRowCount(
1906 $table, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1908 $conds = $this->normalizeConditions( $conds, $fname );
1909 $column = $this->extractSingleFieldFromList( $var );
1910 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1911 $conds[] = "$column IS NOT NULL";
1914 $res = $this->select(
1915 $table, [ 'rowcount' => 'COUNT(*)' ], $conds, $fname, $options, $join_conds
1917 $row = $res ?
$this->fetchRow( $res ) : [];
1919 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1922 public function selectRowCount(
1923 $tables, $var = '*', $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
1925 $conds = $this->normalizeConditions( $conds, $fname );
1926 $column = $this->extractSingleFieldFromList( $var );
1927 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
1928 $conds[] = "$column IS NOT NULL";
1931 $res = $this->select(
1933 'tmp_count' => $this->buildSelectSubquery(
1942 [ 'rowcount' => 'COUNT(*)' ],
1946 $row = $res ?
$this->fetchRow( $res ) : [];
1948 return isset( $row['rowcount'] ) ?
(int)$row['rowcount'] : 0;
1952 * @param string|array $options
1955 private function selectOptionsIncludeLocking( $options ) {
1956 $options = (array)$options;
1957 foreach ( [ 'FOR UPDATE', 'LOCK IN SHARE MODE' ] as $lock ) {
1958 if ( in_array( $lock, $options, true ) ) {
1967 * @param array|string $fields
1968 * @param array|string $options
1971 private function selectFieldsOrOptionsAggregate( $fields, $options ) {
1972 foreach ( (array)$options as $key => $value ) {
1973 if ( is_string( $key ) ) {
1974 if ( preg_match( '/^(?:GROUP BY|HAVING)$/i', $key ) ) {
1977 } elseif ( is_string( $value ) ) {
1978 if ( preg_match( '/^(?:DISTINCT|DISTINCTROW)$/i', $value ) ) {
1984 $regex = '/^(?:COUNT|MIN|MAX|SUM|GROUP_CONCAT|LISTAGG|ARRAY_AGG)\s*\\(/i';
1985 foreach ( (array)$fields as $field ) {
1986 if ( is_string( $field ) && preg_match( $regex, $field ) ) {
1995 * @param array|string $conds
1996 * @param string $fname
1999 final protected function normalizeConditions( $conds, $fname ) {
2000 if ( $conds === null ||
$conds === false ) {
2001 $this->queryLogger
->warning(
2005 . ' with incorrect parameters: $conds must be a string or an array'
2010 if ( !is_array( $conds ) ) {
2011 $conds = ( $conds === '' ) ?
[] : [ $conds ];
2018 * @param array|string $var Field parameter in the style of select()
2019 * @return string|null Column name or null; ignores aliases
2020 * @throws DBUnexpectedError Errors out if multiple columns are given
2022 final protected function extractSingleFieldFromList( $var ) {
2023 if ( is_array( $var ) ) {
2026 } elseif ( count( $var ) == 1 ) {
2027 $column = $var[0] ??
reset( $var );
2029 throw new DBUnexpectedError( $this, __METHOD__
. ': got multiple columns' );
2038 public function lockForUpdate(
2039 $table, $conds = '', $fname = __METHOD__
, $options = [], $join_conds = []
2041 if ( !$this->trxLevel() && !$this->getFlag( self
::DBO_TRX
) ) {
2042 throw new DBUnexpectedError(
2044 __METHOD__
. ': no transaction is active nor is DBO_TRX set'
2048 $options = (array)$options;
2049 $options[] = 'FOR UPDATE';
2051 return $this->selectRowCount( $table, '*', $conds, $fname, $options, $join_conds );
2054 public function fieldExists( $table, $field, $fname = __METHOD__
) {
2055 $info = $this->fieldInfo( $table, $field );
2060 public function indexExists( $table, $index, $fname = __METHOD__
) {
2061 if ( !$this->tableExists( $table ) ) {
2065 $info = $this->indexInfo( $table, $index, $fname );
2066 if ( is_null( $info ) ) {
2069 return $info !== false;
2073 abstract public function tableExists( $table, $fname = __METHOD__
);
2075 public function indexUnique( $table, $index ) {
2076 $indexInfo = $this->indexInfo( $table, $index );
2078 if ( !$indexInfo ) {
2082 return !$indexInfo[0]->Non_unique
;
2086 * Helper for Database::insert().
2088 * @param array $options
2091 protected function makeInsertOptions( $options ) {
2092 return implode( ' ', $options );
2095 public function insert( $table, $a, $fname = __METHOD__
, $options = [] ) {
2096 # No rows to insert, easy just return now
2097 if ( !count( $a ) ) {
2101 $table = $this->tableName( $table );
2103 if ( !is_array( $options ) ) {
2104 $options = [ $options ];
2107 $options = $this->makeInsertOptions( $options );
2109 if ( isset( $a[0] ) && is_array( $a[0] ) ) {
2111 $keys = array_keys( $a[0] );
2114 $keys = array_keys( $a );
2117 $sql = 'INSERT ' . $options .
2118 " INTO $table (" . implode( ',', $keys ) . ') VALUES ';
2122 foreach ( $a as $row ) {
2128 $sql .= '(' . $this->makeList( $row ) . ')';
2131 $sql .= '(' . $this->makeList( $a ) . ')';
2134 $this->query( $sql, $fname );
2140 * Make UPDATE options array for Database::makeUpdateOptions
2142 * @param array $options
2145 protected function makeUpdateOptionsArray( $options ) {
2146 if ( !is_array( $options ) ) {
2147 $options = [ $options ];
2152 if ( in_array( 'IGNORE', $options ) ) {
2160 * Make UPDATE options for the Database::update function
2162 * @param array $options The options passed to Database::update
2165 protected function makeUpdateOptions( $options ) {
2166 $opts = $this->makeUpdateOptionsArray( $options );
2168 return implode( ' ', $opts );
2171 public function update( $table, $values, $conds, $fname = __METHOD__
, $options = [] ) {
2172 $table = $this->tableName( $table );
2173 $opts = $this->makeUpdateOptions( $options );
2174 $sql = "UPDATE $opts $table SET " . $this->makeList( $values, self
::LIST_SET
);
2176 if ( $conds !== [] && $conds !== '*' ) {
2177 $sql .= " WHERE " . $this->makeList( $conds, self
::LIST_AND
);
2180 $this->query( $sql, $fname );
2185 public function makeList( $a, $mode = self
::LIST_COMMA
) {
2186 if ( !is_array( $a ) ) {
2187 throw new DBUnexpectedError( $this, __METHOD__
. ' called with incorrect parameters' );
2193 foreach ( $a as $field => $value ) {
2195 if ( $mode == self
::LIST_AND
) {
2197 } elseif ( $mode == self
::LIST_OR
) {
2206 if ( ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_numeric( $field ) ) {
2207 $list .= "($value)";
2208 } elseif ( $mode == self
::LIST_SET
&& is_numeric( $field ) ) {
2211 ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) && is_array( $value )
2213 // Remove null from array to be handled separately if found
2214 $includeNull = false;
2215 foreach ( array_keys( $value, null, true ) as $nullKey ) {
2216 $includeNull = true;
2217 unset( $value[$nullKey] );
2219 if ( count( $value ) == 0 && !$includeNull ) {
2220 throw new InvalidArgumentException(
2221 __METHOD__
. ": empty input for field $field" );
2222 } elseif ( count( $value ) == 0 ) {
2223 // only check if $field is null
2224 $list .= "$field IS NULL";
2226 // IN clause contains at least one valid element
2227 if ( $includeNull ) {
2228 // Group subconditions to ensure correct precedence
2231 if ( count( $value ) == 1 ) {
2232 // Special-case single values, as IN isn't terribly efficient
2233 // Don't necessarily assume the single key is 0; we don't
2234 // enforce linear numeric ordering on other arrays here.
2235 $value = array_values( $value )[0];
2236 $list .= $field . " = " . $this->addQuotes( $value );
2238 $list .= $field . " IN (" . $this->makeList( $value ) . ") ";
2240 // if null present in array, append IS NULL
2241 if ( $includeNull ) {
2242 $list .= " OR $field IS NULL)";
2245 } elseif ( $value === null ) {
2246 if ( $mode == self
::LIST_AND ||
$mode == self
::LIST_OR
) {
2247 $list .= "$field IS ";
2248 } elseif ( $mode == self
::LIST_SET
) {
2249 $list .= "$field = ";
2254 $mode == self
::LIST_AND ||
$mode == self
::LIST_OR ||
$mode == self
::LIST_SET
2256 $list .= "$field = ";
2258 $list .= $mode == self
::LIST_NAMES ?
$value : $this->addQuotes( $value );
2265 public function makeWhereFrom2d( $data, $baseKey, $subKey ) {
2268 foreach ( $data as $base => $sub ) {
2269 if ( count( $sub ) ) {
2270 $conds[] = $this->makeList(
2271 [ $baseKey => $base, $subKey => array_keys( $sub ) ],
2277 return $this->makeList( $conds, self
::LIST_OR
);
2279 // Nothing to search for...
2284 public function aggregateValue( $valuedata, $valuename = 'value' ) {
2288 public function bitNot( $field ) {
2292 public function bitAnd( $fieldLeft, $fieldRight ) {
2293 return "($fieldLeft & $fieldRight)";
2296 public function bitOr( $fieldLeft, $fieldRight ) {
2297 return "($fieldLeft | $fieldRight)";
2300 public function buildConcat( $stringList ) {
2301 return 'CONCAT(' . implode( ',', $stringList ) . ')';
2304 public function buildGroupConcatField(
2305 $delim, $table, $field, $conds = '', $join_conds = []
2307 $fld = "GROUP_CONCAT($field SEPARATOR " . $this->addQuotes( $delim ) . ')';
2309 return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
2312 public function buildSubstring( $input, $startPosition, $length = null ) {
2313 $this->assertBuildSubstringParams( $startPosition, $length );
2314 $functionBody = "$input FROM $startPosition";
2315 if ( $length !== null ) {
2316 $functionBody .= " FOR $length";
2318 return 'SUBSTRING(' . $functionBody . ')';
2322 * Check type and bounds for parameters to self::buildSubstring()
2324 * All supported databases have substring functions that behave the same for
2325 * positive $startPosition and non-negative $length, but behaviors differ when
2326 * given 0 or negative $startPosition or negative $length. The simplest
2327 * solution to that is to just forbid those values.
2329 * @param int $startPosition
2330 * @param int|null $length
2333 protected function assertBuildSubstringParams( $startPosition, $length ) {
2334 if ( !is_int( $startPosition ) ||
$startPosition <= 0 ) {
2335 throw new InvalidArgumentException(
2336 '$startPosition must be a positive integer'
2339 if ( !( is_int( $length ) && $length >= 0 ||
$length === null ) ) {
2340 throw new InvalidArgumentException(
2341 '$length must be null or an integer greater than or equal to 0'
2346 public function buildStringCast( $field ) {
2347 // In theory this should work for any standards-compliant
2348 // SQL implementation, although it may not be the best way to do it.
2349 return "CAST( $field AS CHARACTER )";
2352 public function buildIntegerCast( $field ) {
2353 return 'CAST( ' . $field . ' AS INTEGER )';
2356 public function buildSelectSubquery(
2357 $table, $vars, $conds = '', $fname = __METHOD__
,
2358 $options = [], $join_conds = []
2360 return new Subquery(
2361 $this->selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds )
2365 public function databasesAreIndependent() {
2369 final public function selectDB( $db ) {
2370 $this->selectDomain( new DatabaseDomain(
2372 $this->currentDomain
->getSchema(),
2373 $this->currentDomain
->getTablePrefix()
2379 final public function selectDomain( $domain ) {
2380 $this->doSelectDomain( DatabaseDomain
::newFromId( $domain ) );
2383 protected function doSelectDomain( DatabaseDomain
$domain ) {
2384 $this->currentDomain
= $domain;
2387 public function getDBname() {
2388 return $this->currentDomain
->getDatabase();
2391 public function getServer() {
2392 return $this->server
;
2395 public function tableName( $name, $format = 'quoted' ) {
2396 if ( $name instanceof Subquery
) {
2397 throw new DBUnexpectedError(
2399 __METHOD__
. ': got Subquery instance when expecting a string'
2403 # Skip the entire process when we have a string quoted on both ends.
2404 # Note that we check the end so that we will still quote any use of
2405 # use of `database`.table. But won't break things if someone wants
2406 # to query a database table with a dot in the name.
2407 if ( $this->isQuotedIdentifier( $name ) ) {
2411 # Lets test for any bits of text that should never show up in a table
2412 # name. Basically anything like JOIN or ON which are actually part of
2413 # SQL queries, but may end up inside of the table value to combine
2414 # sql. Such as how the API is doing.
2415 # Note that we use a whitespace test rather than a \b test to avoid
2416 # any remote case where a word like on may be inside of a table name
2417 # surrounded by symbols which may be considered word breaks.
2418 if ( preg_match( '/(^|\s)(DISTINCT|JOIN|ON|AS)(\s|$)/i', $name ) !== 0 ) {
2419 $this->queryLogger
->warning(
2420 __METHOD__
. ": use of subqueries is not supported this way",
2421 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
2427 # Split database and table into proper variables.
2428 list( $database, $schema, $prefix, $table ) = $this->qualifiedTableComponents( $name );
2430 # Quote $table and apply the prefix if not quoted.
2431 # $tableName might be empty if this is called from Database::replaceVars()
2432 $tableName = "{$prefix}{$table}";
2433 if ( $format === 'quoted'
2434 && !$this->isQuotedIdentifier( $tableName )
2435 && $tableName !== ''
2437 $tableName = $this->addIdentifierQuotes( $tableName );
2440 # Quote $schema and $database and merge them with the table name if needed
2441 $tableName = $this->prependDatabaseOrSchema( $schema, $tableName, $format );
2442 $tableName = $this->prependDatabaseOrSchema( $database, $tableName, $format );
2448 * Get the table components needed for a query given the currently selected database
2450 * @param string $name Table name in the form of db.schema.table, db.table, or table
2451 * @return array (DB name or "" for default, schema name, table prefix, table name)
2453 protected function qualifiedTableComponents( $name ) {
2454 # We reverse the explode so that database.table and table both output the correct table.
2455 $dbDetails = explode( '.', $name, 3 );
2456 if ( count( $dbDetails ) == 3 ) {
2457 list( $database, $schema, $table ) = $dbDetails;
2458 # We don't want any prefix added in this case
2460 } elseif ( count( $dbDetails ) == 2 ) {
2461 list( $database, $table ) = $dbDetails;
2462 # We don't want any prefix added in this case
2464 # In dbs that support it, $database may actually be the schema
2465 # but that doesn't affect any of the functionality here
2468 list( $table ) = $dbDetails;
2469 if ( isset( $this->tableAliases
[$table] ) ) {
2470 $database = $this->tableAliases
[$table]['dbname'];
2471 $schema = is_string( $this->tableAliases
[$table]['schema'] )
2472 ?
$this->tableAliases
[$table]['schema']
2473 : $this->relationSchemaQualifier();
2474 $prefix = is_string( $this->tableAliases
[$table]['prefix'] )
2475 ?
$this->tableAliases
[$table]['prefix']
2476 : $this->tablePrefix();
2479 $schema = $this->relationSchemaQualifier(); # Default schema
2480 $prefix = $this->tablePrefix(); # Default prefix
2484 return [ $database, $schema, $prefix, $table ];
2488 * @param string|null $namespace Database or schema
2489 * @param string $relation Name of table, view, sequence, etc...
2490 * @param string $format One of (raw, quoted)
2491 * @return string Relation name with quoted and merged $namespace as needed
2493 private function prependDatabaseOrSchema( $namespace, $relation, $format ) {
2494 if ( strlen( $namespace ) ) {
2495 if ( $format === 'quoted' && !$this->isQuotedIdentifier( $namespace ) ) {
2496 $namespace = $this->addIdentifierQuotes( $namespace );
2498 $relation = $namespace . '.' . $relation;
2504 public function tableNames() {
2505 $inArray = func_get_args();
2508 foreach ( $inArray as $name ) {
2509 $retVal[$name] = $this->tableName( $name );
2515 public function tableNamesN() {
2516 $inArray = func_get_args();
2519 foreach ( $inArray as $name ) {
2520 $retVal[] = $this->tableName( $name );
2527 * Get an aliased table name
2529 * This returns strings like "tableName AS newTableName" for aliased tables
2530 * and "(SELECT * from tableA) newTablename" for subqueries (e.g. derived tables)
2532 * @see Database::tableName()
2533 * @param string|Subquery $table Table name or object with a 'sql' field
2534 * @param string|bool $alias Table alias (optional)
2535 * @return string SQL name for aliased table. Will not alias a table to its own name
2537 protected function tableNameWithAlias( $table, $alias = false ) {
2538 if ( is_string( $table ) ) {
2539 $quotedTable = $this->tableName( $table );
2540 } elseif ( $table instanceof Subquery
) {
2541 $quotedTable = (string)$table;
2543 throw new InvalidArgumentException( "Table must be a string or Subquery" );
2546 if ( $alias === false ||
$alias === $table ) {
2547 if ( $table instanceof Subquery
) {
2548 throw new InvalidArgumentException( "Subquery table missing alias" );
2551 return $quotedTable;
2553 return $quotedTable . ' ' . $this->addIdentifierQuotes( $alias );
2558 * Gets an array of aliased table names
2560 * @param array $tables [ [alias] => table ]
2561 * @return string[] See tableNameWithAlias()
2563 protected function tableNamesWithAlias( $tables ) {
2565 foreach ( $tables as $alias => $table ) {
2566 if ( is_numeric( $alias ) ) {
2569 $retval[] = $this->tableNameWithAlias( $table, $alias );
2576 * Get an aliased field name
2577 * e.g. fieldName AS newFieldName
2579 * @param string $name Field name
2580 * @param string|bool $alias Alias (optional)
2581 * @return string SQL name for aliased field. Will not alias a field to its own name
2583 protected function fieldNameWithAlias( $name, $alias = false ) {
2584 if ( !$alias ||
(string)$alias === (string)$name ) {
2587 return $name . ' AS ' . $this->addIdentifierQuotes( $alias ); // PostgreSQL needs AS
2592 * Gets an array of aliased field names
2594 * @param array $fields [ [alias] => field ]
2595 * @return string[] See fieldNameWithAlias()
2597 protected function fieldNamesWithAlias( $fields ) {
2599 foreach ( $fields as $alias => $field ) {
2600 if ( is_numeric( $alias ) ) {
2603 $retval[] = $this->fieldNameWithAlias( $field, $alias );
2610 * Get the aliased table name clause for a FROM clause
2611 * which might have a JOIN and/or USE INDEX or IGNORE INDEX clause
2613 * @param array $tables ( [alias] => table )
2614 * @param array $use_index Same as for select()
2615 * @param array $ignore_index Same as for select()
2616 * @param array $join_conds Same as for select()
2619 protected function tableNamesWithIndexClauseOrJOIN(
2620 $tables, $use_index = [], $ignore_index = [], $join_conds = []
2624 $use_index = (array)$use_index;
2625 $ignore_index = (array)$ignore_index;
2626 $join_conds = (array)$join_conds;
2628 foreach ( $tables as $alias => $table ) {
2629 if ( !is_string( $alias ) ) {
2630 // No alias? Set it equal to the table name
2634 if ( is_array( $table ) ) {
2635 // A parenthesized group
2636 if ( count( $table ) > 1 ) {
2637 $joinedTable = '(' .
2638 $this->tableNamesWithIndexClauseOrJOIN(
2639 $table, $use_index, $ignore_index, $join_conds ) . ')';
2642 $innerTable = reset( $table );
2643 $innerAlias = key( $table );
2644 $joinedTable = $this->tableNameWithAlias(
2646 is_string( $innerAlias ) ?
$innerAlias : $innerTable
2650 $joinedTable = $this->tableNameWithAlias( $table, $alias );
2653 // Is there a JOIN clause for this table?
2654 if ( isset( $join_conds[$alias] ) ) {
2655 list( $joinType, $conds ) = $join_conds[$alias];
2656 $tableClause = $joinType;
2657 $tableClause .= ' ' . $joinedTable;
2658 if ( isset( $use_index[$alias] ) ) { // has USE INDEX?
2659 $use = $this->useIndexClause( implode( ',', (array)$use_index[$alias] ) );
2661 $tableClause .= ' ' . $use;
2664 if ( isset( $ignore_index[$alias] ) ) { // has IGNORE INDEX?
2665 $ignore = $this->ignoreIndexClause(
2666 implode( ',', (array)$ignore_index[$alias] ) );
2667 if ( $ignore != '' ) {
2668 $tableClause .= ' ' . $ignore;
2671 $on = $this->makeList( (array)$conds, self
::LIST_AND
);
2673 $tableClause .= ' ON (' . $on . ')';
2676 $retJOIN[] = $tableClause;
2677 } elseif ( isset( $use_index[$alias] ) ) {
2678 // Is there an INDEX clause for this table?
2679 $tableClause = $joinedTable;
2680 $tableClause .= ' ' . $this->useIndexClause(
2681 implode( ',', (array)$use_index[$alias] )
2684 $ret[] = $tableClause;
2685 } elseif ( isset( $ignore_index[$alias] ) ) {
2686 // Is there an INDEX clause for this table?
2687 $tableClause = $joinedTable;
2688 $tableClause .= ' ' . $this->ignoreIndexClause(
2689 implode( ',', (array)$ignore_index[$alias] )
2692 $ret[] = $tableClause;
2694 $tableClause = $joinedTable;
2696 $ret[] = $tableClause;
2700 // We can't separate explicit JOIN clauses with ',', use ' ' for those
2701 $implicitJoins = implode( ',', $ret );
2702 $explicitJoins = implode( ' ', $retJOIN );
2704 // Compile our final table clause
2705 return implode( ' ', [ $implicitJoins, $explicitJoins ] );
2709 * Allows for index remapping in queries where this is not consistent across DBMS
2711 * @param string $index
2714 protected function indexName( $index ) {
2715 return $this->indexAliases
[$index] ??
$index;
2718 public function addQuotes( $s ) {
2719 if ( $s instanceof Blob
) {
2722 if ( $s === null ) {
2724 } elseif ( is_bool( $s ) ) {
2727 # This will also quote numeric values. This should be harmless,
2728 # and protects against weird problems that occur when they really
2729 # _are_ strings such as article titles and string->number->string
2730 # conversion is not 1:1.
2731 return "'" . $this->strencode( $s ) . "'";
2735 public function addIdentifierQuotes( $s ) {
2736 return '"' . str_replace( '"', '""', $s ) . '"';
2740 * Returns if the given identifier looks quoted or not according to
2741 * the database convention for quoting identifiers .
2743 * @note Do not use this to determine if untrusted input is safe.
2744 * A malicious user can trick this function.
2745 * @param string $name
2748 public function isQuotedIdentifier( $name ) {
2749 return $name[0] == '"' && substr( $name, -1, 1 ) == '"';
2754 * @param string $escapeChar
2757 protected function escapeLikeInternal( $s, $escapeChar = '`' ) {
2758 return str_replace( [ $escapeChar, '%', '_' ],
2759 [ "{$escapeChar}{$escapeChar}", "{$escapeChar}%", "{$escapeChar}_" ],
2763 public function buildLike( $param, ...$params ) {
2764 if ( is_array( $param ) ) {
2767 $params = func_get_args();
2772 // We use ` instead of \ as the default LIKE escape character, since addQuotes()
2773 // may escape backslashes, creating problems of double escaping. The `
2774 // character has good cross-DBMS compatibility, avoiding special operators
2775 // in MS SQL like ^ and %
2778 foreach ( $params as $value ) {
2779 if ( $value instanceof LikeMatch
) {
2780 $s .= $value->toString();
2782 $s .= $this->escapeLikeInternal( $value, $escapeChar );
2787 $this->addQuotes( $s ) . ' ESCAPE ' . $this->addQuotes( $escapeChar ) . ' ';
2790 public function anyChar() {
2791 return new LikeMatch( '_' );
2794 public function anyString() {
2795 return new LikeMatch( '%' );
2798 public function nextSequenceValue( $seqName ) {
2803 * USE INDEX clause. Unlikely to be useful for anything but MySQL. This
2804 * is only needed because a) MySQL must be as efficient as possible due to
2805 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2806 * which index to pick. Anyway, other databases might have different
2807 * indexes on a given table. So don't bother overriding this unless you're
2809 * @param string $index
2812 public function useIndexClause( $index ) {
2817 * IGNORE INDEX clause. Unlikely to be useful for anything but MySQL. This
2818 * is only needed because a) MySQL must be as efficient as possible due to
2819 * its use on Wikipedia, and b) MySQL 4.0 is kind of dumb sometimes about
2820 * which index to pick. Anyway, other databases might have different
2821 * indexes on a given table. So don't bother overriding this unless you're
2823 * @param string $index
2826 public function ignoreIndexClause( $index ) {
2830 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__
) {
2831 if ( count( $rows ) == 0 ) {
2835 $uniqueIndexes = (array)$uniqueIndexes;
2837 if ( !is_array( reset( $rows ) ) ) {
2842 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2843 $affectedRowCount = 0;
2844 foreach ( $rows as $row ) {
2845 // Delete rows which collide with this one
2846 $indexWhereClauses = [];
2847 foreach ( $uniqueIndexes as $index ) {
2848 $indexColumns = (array)$index;
2849 $indexRowValues = array_intersect_key( $row, array_flip( $indexColumns ) );
2850 if ( count( $indexRowValues ) != count( $indexColumns ) ) {
2851 throw new DBUnexpectedError(
2853 'New record does not provide all values for unique key (' .
2854 implode( ', ', $indexColumns ) . ')'
2856 } elseif ( in_array( null, $indexRowValues, true ) ) {
2857 throw new DBUnexpectedError(
2859 'New record has a null value for unique key (' .
2860 implode( ', ', $indexColumns ) . ')'
2863 $indexWhereClauses[] = $this->makeList( $indexRowValues, LIST_AND
);
2866 if ( $indexWhereClauses ) {
2867 $this->delete( $table, $this->makeList( $indexWhereClauses, LIST_OR
), $fname );
2868 $affectedRowCount +
= $this->affectedRows();
2871 // Now insert the row
2872 $this->insert( $table, $row, $fname );
2873 $affectedRowCount +
= $this->affectedRows();
2875 $this->endAtomic( $fname );
2876 $this->affectedRowCount
= $affectedRowCount;
2877 } catch ( Exception
$e ) {
2878 $this->cancelAtomic( $fname );
2884 * REPLACE query wrapper for MySQL and SQLite, which have a native REPLACE
2887 * @param string $table Table name
2888 * @param array|string $rows Row(s) to insert
2889 * @param string $fname Caller function name
2891 protected function nativeReplace( $table, $rows, $fname ) {
2892 $table = $this->tableName( $table );
2895 if ( !is_array( reset( $rows ) ) ) {
2899 $sql = "REPLACE INTO $table (" . implode( ',', array_keys( $rows[0] ) ) . ') VALUES ';
2902 foreach ( $rows as $row ) {
2909 $sql .= '(' . $this->makeList( $row ) . ')';
2912 $this->query( $sql, $fname );
2915 public function upsert( $table, array $rows, $uniqueIndexes, array $set,
2918 if ( $rows === [] ) {
2919 return true; // nothing to do
2922 $uniqueIndexes = (array)$uniqueIndexes;
2923 if ( !is_array( reset( $rows ) ) ) {
2927 if ( count( $uniqueIndexes ) ) {
2928 $clauses = []; // list WHERE clauses that each identify a single row
2929 foreach ( $rows as $row ) {
2930 foreach ( $uniqueIndexes as $index ) {
2931 $index = is_array( $index ) ?
$index : [ $index ]; // columns
2932 $rowKey = []; // unique key to this row
2933 foreach ( $index as $column ) {
2934 $rowKey[$column] = $row[$column];
2936 $clauses[] = $this->makeList( $rowKey, self
::LIST_AND
);
2939 $where = [ $this->makeList( $clauses, self
::LIST_OR
) ];
2944 $affectedRowCount = 0;
2946 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
2947 # Update any existing conflicting row(s)
2948 if ( $where !== false ) {
2949 $this->update( $table, $set, $where, $fname );
2950 $affectedRowCount +
= $this->affectedRows();
2952 # Now insert any non-conflicting row(s)
2953 $this->insert( $table, $rows, $fname, [ 'IGNORE' ] );
2954 $affectedRowCount +
= $this->affectedRows();
2955 $this->endAtomic( $fname );
2956 $this->affectedRowCount
= $affectedRowCount;
2957 } catch ( Exception
$e ) {
2958 $this->cancelAtomic( $fname );
2965 public function deleteJoin( $delTable, $joinTable, $delVar, $joinVar, $conds,
2969 throw new DBUnexpectedError( $this, __METHOD__
. ' called with empty $conds' );
2972 $delTable = $this->tableName( $delTable );
2973 $joinTable = $this->tableName( $joinTable );
2974 $sql = "DELETE FROM $delTable WHERE $delVar IN (SELECT $joinVar FROM $joinTable ";
2975 if ( $conds != '*' ) {
2976 $sql .= 'WHERE ' . $this->makeList( $conds, self
::LIST_AND
);
2980 $this->query( $sql, $fname );
2983 public function textFieldSize( $table, $field ) {
2984 $table = $this->tableName( $table );
2985 $sql = "SHOW COLUMNS FROM $table LIKE \"$field\"";
2986 $res = $this->query( $sql, __METHOD__
);
2987 $row = $this->fetchObject( $res );
2991 if ( preg_match( '/\((.*)\)/', $row->Type
, $m ) ) {
3000 public function delete( $table, $conds, $fname = __METHOD__
) {
3002 throw new DBUnexpectedError( $this, __METHOD__
. ' called with no conditions' );
3005 $table = $this->tableName( $table );
3006 $sql = "DELETE FROM $table";
3008 if ( $conds != '*' ) {
3009 if ( is_array( $conds ) ) {
3010 $conds = $this->makeList( $conds, self
::LIST_AND
);
3012 $sql .= ' WHERE ' . $conds;
3015 $this->query( $sql, $fname );
3020 final public function insertSelect(
3021 $destTable, $srcTable, $varMap, $conds,
3022 $fname = __METHOD__
, $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3024 static $hints = [ 'NO_AUTO_COLUMNS' ];
3026 $insertOptions = (array)$insertOptions;
3027 $selectOptions = (array)$selectOptions;
3029 if ( $this->cliMode
&& $this->isInsertSelectSafe( $insertOptions, $selectOptions ) ) {
3030 // For massive migrations with downtime, we don't want to select everything
3031 // into memory and OOM, so do all this native on the server side if possible.
3032 $this->nativeInsertSelect(
3038 array_diff( $insertOptions, $hints ),
3043 $this->nonNativeInsertSelect(
3049 array_diff( $insertOptions, $hints ),
3059 * @param array $insertOptions INSERT options
3060 * @param array $selectOptions SELECT options
3061 * @return bool Whether an INSERT SELECT with these options will be replication safe
3064 protected function isInsertSelectSafe( array $insertOptions, array $selectOptions ) {
3069 * Implementation of insertSelect() based on select() and insert()
3071 * @see IDatabase::insertSelect()
3073 * @param string $destTable
3074 * @param string|array $srcTable
3075 * @param array $varMap
3076 * @param array $conds
3077 * @param string $fname
3078 * @param array $insertOptions
3079 * @param array $selectOptions
3080 * @param array $selectJoinConds
3082 protected function nonNativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3083 $fname = __METHOD__
,
3084 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3086 // For web requests, do a locking SELECT and then INSERT. This puts the SELECT burden
3087 // on only the master (without needing row-based-replication). It also makes it easy to
3088 // know how big the INSERT is going to be.
3090 foreach ( $varMap as $dstColumn => $sourceColumnOrSql ) {
3091 $fields[] = $this->fieldNameWithAlias( $sourceColumnOrSql, $dstColumn );
3093 $selectOptions[] = 'FOR UPDATE';
3094 $res = $this->select(
3095 $srcTable, implode( ',', $fields ), $conds, $fname, $selectOptions, $selectJoinConds
3102 $affectedRowCount = 0;
3103 $this->startAtomic( $fname, self
::ATOMIC_CANCELABLE
);
3106 foreach ( $res as $row ) {
3107 $rows[] = (array)$row;
3109 // Avoid inserts that are too huge
3110 if ( count( $rows ) >= $this->nonNativeInsertSelectBatchSize
) {
3111 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
3115 $affectedRowCount +
= $this->affectedRows();
3119 if ( $rows && $ok ) {
3120 $ok = $this->insert( $destTable, $rows, $fname, $insertOptions );
3122 $affectedRowCount +
= $this->affectedRows();
3126 $this->endAtomic( $fname );
3127 $this->affectedRowCount
= $affectedRowCount;
3129 $this->cancelAtomic( $fname );
3131 } catch ( Exception
$e ) {
3132 $this->cancelAtomic( $fname );
3138 * Native server-side implementation of insertSelect() for situations where
3139 * we don't want to select everything into memory
3141 * @see IDatabase::insertSelect()
3142 * @param string $destTable
3143 * @param string|array $srcTable
3144 * @param array $varMap
3145 * @param array $conds
3146 * @param string $fname
3147 * @param array $insertOptions
3148 * @param array $selectOptions
3149 * @param array $selectJoinConds
3151 protected function nativeInsertSelect( $destTable, $srcTable, $varMap, $conds,
3152 $fname = __METHOD__
,
3153 $insertOptions = [], $selectOptions = [], $selectJoinConds = []
3155 $destTable = $this->tableName( $destTable );
3157 if ( !is_array( $insertOptions ) ) {
3158 $insertOptions = [ $insertOptions ];
3161 $insertOptions = $this->makeInsertOptions( $insertOptions );
3163 $selectSql = $this->selectSQLText(
3165 array_values( $varMap ),
3172 $sql = "INSERT $insertOptions" .
3173 " INTO $destTable (" . implode( ',', array_keys( $varMap ) ) . ') ' .
3176 $this->query( $sql, $fname );
3179 public function limitResult( $sql, $limit, $offset = false ) {
3180 if ( !is_numeric( $limit ) ) {
3181 throw new DBUnexpectedError(
3183 "Invalid non-numeric limit passed to " . __METHOD__
3186 // This version works in MySQL and SQLite. It will very likely need to be
3187 // overridden for most other RDBMS subclasses.
3188 return "$sql LIMIT "
3189 . ( ( is_numeric( $offset ) && $offset != 0 ) ?
"{$offset}," : "" )
3193 public function unionSupportsOrderAndLimit() {
3194 return true; // True for almost every DB supported
3197 public function unionQueries( $sqls, $all ) {
3198 $glue = $all ?
') UNION ALL (' : ') UNION (';
3200 return '(' . implode( $glue, $sqls ) . ')';
3203 public function unionConditionPermutations(
3204 $table, $vars, array $permute_conds, $extra_conds = '', $fname = __METHOD__
,
3205 $options = [], $join_conds = []
3207 // First, build the Cartesian product of $permute_conds
3209 foreach ( $permute_conds as $field => $values ) {
3211 // Skip empty $values
3214 $values = array_unique( $values ); // For sanity
3216 foreach ( $conds as $cond ) {
3217 foreach ( $values as $value ) {
3218 $cond[$field] = $value;
3219 $newConds[] = $cond; // Arrays are by-value, not by-reference, so this works
3225 $extra_conds = $extra_conds === '' ?
[] : (array)$extra_conds;
3227 // If there's just one condition and no subordering, hand off to
3228 // selectSQLText directly.
3229 if ( count( $conds ) === 1 &&
3230 ( !isset( $options['INNER ORDER BY'] ) ||
!$this->unionSupportsOrderAndLimit() )
3232 return $this->selectSQLText(
3233 $table, $vars, $conds[0] +
$extra_conds, $fname, $options, $join_conds
3237 // Otherwise, we need to pull out the order and limit to apply after
3238 // the union. Then build the SQL queries for each set of conditions in
3239 // $conds. Then union them together (using UNION ALL, because the
3240 // product *should* already be distinct).
3241 $orderBy = $this->makeOrderBy( $options );
3242 $limit = $options['LIMIT'] ??
null;
3243 $offset = $options['OFFSET'] ??
false;
3244 $all = empty( $options['NOTALL'] ) && !in_array( 'NOTALL', $options );
3245 if ( !$this->unionSupportsOrderAndLimit() ) {
3246 unset( $options['ORDER BY'], $options['LIMIT'], $options['OFFSET'] );
3248 if ( array_key_exists( 'INNER ORDER BY', $options ) ) {
3249 $options['ORDER BY'] = $options['INNER ORDER BY'];
3251 if ( $limit !== null && is_numeric( $offset ) && $offset != 0 ) {
3252 // We need to increase the limit by the offset rather than
3253 // using the offset directly, otherwise it'll skip incorrectly
3254 // in the subqueries.
3255 $options['LIMIT'] = $limit +
$offset;
3256 unset( $options['OFFSET'] );
3261 foreach ( $conds as $cond ) {
3262 $sqls[] = $this->selectSQLText(
3263 $table, $vars, $cond +
$extra_conds, $fname, $options, $join_conds
3266 $sql = $this->unionQueries( $sqls, $all ) . $orderBy;
3267 if ( $limit !== null ) {
3268 $sql = $this->limitResult( $sql, $limit, $offset );
3274 public function conditional( $cond, $trueVal, $falseVal ) {
3275 if ( is_array( $cond ) ) {
3276 $cond = $this->makeList( $cond, self
::LIST_AND
);
3279 return " (CASE WHEN $cond THEN $trueVal ELSE $falseVal END) ";
3282 public function strreplace( $orig, $old, $new ) {
3283 return "REPLACE({$orig}, {$old}, {$new})";
3286 public function getServerUptime() {
3290 public function wasDeadlock() {
3294 public function wasLockTimeout() {
3298 public function wasConnectionLoss() {
3299 return $this->wasConnectionError( $this->lastErrno() );
3302 public function wasReadOnlyError() {
3306 public function wasErrorReissuable() {
3308 $this->wasDeadlock() ||
3309 $this->wasLockTimeout() ||
3310 $this->wasConnectionLoss()
3315 * Do not use this method outside of Database/DBError classes
3317 * @param int|string $errno
3318 * @return bool Whether the given query error was a connection drop
3320 public function wasConnectionError( $errno ) {
3325 * @return bool Whether it is known that the last query error only caused statement rollback
3326 * @note This is for backwards compatibility for callers catching DBError exceptions in
3327 * order to ignore problems like duplicate key errors or foriegn key violations
3330 protected function wasKnownStatementRollbackError() {
3331 return false; // don't know; it could have caused a transaction rollback
3334 public function deadlockLoop() {
3335 $args = func_get_args();
3336 $function = array_shift( $args );
3337 $tries = self
::$DEADLOCK_TRIES;
3339 $this->begin( __METHOD__
);
3342 /** @var Exception $e */
3346 $retVal = $function( ...$args );
3348 } catch ( DBQueryError
$e ) {
3349 if ( $this->wasDeadlock() ) {
3350 // Retry after a randomized delay
3351 usleep( mt_rand( self
::$DEADLOCK_DELAY_MIN, self
::$DEADLOCK_DELAY_MAX ) );
3353 // Throw the error back up
3357 } while ( --$tries > 0 );
3359 if ( $tries <= 0 ) {
3360 // Too many deadlocks; give up
3361 $this->rollback( __METHOD__
);
3364 $this->commit( __METHOD__
);
3370 public function masterPosWait( DBMasterPos
$pos, $timeout ) {
3371 # Real waits are implemented in the subclass.
3375 public function getReplicaPos() {
3380 public function getMasterPos() {
3385 public function serverIsReadOnly() {
3389 final public function onTransactionResolution( callable
$callback, $fname = __METHOD__
) {
3390 if ( !$this->trxLevel() ) {
3391 throw new DBUnexpectedError( $this, "No transaction is active" );
3393 $this->trxEndCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3396 final public function onTransactionCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3397 if ( !$this->trxLevel() && $this->getTransactionRoundId() ) {
3398 // Start an implicit transaction similar to how query() does
3399 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3400 $this->trxAutomatic
= true;
3403 $this->trxIdleCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3404 if ( !$this->trxLevel() ) {
3405 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_IDLE
);
3409 final public function onTransactionIdle( callable
$callback, $fname = __METHOD__
) {
3410 $this->onTransactionCommitOrIdle( $callback, $fname );
3413 final public function onTransactionPreCommitOrIdle( callable
$callback, $fname = __METHOD__
) {
3414 if ( !$this->trxLevel() && $this->getTransactionRoundId() ) {
3415 // Start an implicit transaction similar to how query() does
3416 $this->begin( __METHOD__
, self
::TRANSACTION_INTERNAL
);
3417 $this->trxAutomatic
= true;
3420 if ( $this->trxLevel() ) {
3421 $this->trxPreCommitCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3423 // No transaction is active nor will start implicitly, so make one for this callback
3424 $this->startAtomic( __METHOD__
, self
::ATOMIC_CANCELABLE
);
3427 $this->endAtomic( __METHOD__
);
3428 } catch ( Exception
$e ) {
3429 $this->cancelAtomic( __METHOD__
);
3435 final public function onAtomicSectionCancel( callable
$callback, $fname = __METHOD__
) {
3436 if ( !$this->trxLevel() ||
!$this->trxAtomicLevels
) {
3437 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)" );
3439 $this->trxSectionCancelCallbacks
[] = [ $callback, $fname, $this->currentAtomicSectionId() ];
3443 * @return AtomicSectionIdentifier|null ID of the topmost atomic section level
3445 private function currentAtomicSectionId() {
3446 if ( $this->trxLevel() && $this->trxAtomicLevels
) {
3447 $levelInfo = end( $this->trxAtomicLevels
);
3449 return $levelInfo[1];
3456 * Hoist callback ownership for callbacks in a section to a parent section.
3457 * All callbacks should have an owner that is present in trxAtomicLevels.
3458 * @param AtomicSectionIdentifier $old
3459 * @param AtomicSectionIdentifier $new
3461 private function reassignCallbacksForSection(
3462 AtomicSectionIdentifier
$old, AtomicSectionIdentifier
$new
3464 foreach ( $this->trxPreCommitCallbacks
as $key => $info ) {
3465 if ( $info[2] === $old ) {
3466 $this->trxPreCommitCallbacks
[$key][2] = $new;
3469 foreach ( $this->trxIdleCallbacks
as $key => $info ) {
3470 if ( $info[2] === $old ) {
3471 $this->trxIdleCallbacks
[$key][2] = $new;
3474 foreach ( $this->trxEndCallbacks
as $key => $info ) {
3475 if ( $info[2] === $old ) {
3476 $this->trxEndCallbacks
[$key][2] = $new;
3479 foreach ( $this->trxSectionCancelCallbacks
as $key => $info ) {
3480 if ( $info[2] === $old ) {
3481 $this->trxSectionCancelCallbacks
[$key][2] = $new;
3487 * Update callbacks that were owned by cancelled atomic sections.
3489 * Callbacks for "on commit" should never be run if they're owned by a
3490 * section that won't be committed.
3492 * Callbacks for "on resolution" need to reflect that the section was
3493 * rolled back, even if the transaction as a whole commits successfully.
3495 * Callbacks for "on section cancel" should already have been consumed,
3496 * but errors during the cancellation itself can prevent that while still
3497 * destroying the section. Hoist any such callbacks to the new top section,
3498 * which we assume will itself have to be cancelled or rolled back to
3499 * resolve the error.
3501 * @param AtomicSectionIdentifier[] $sectionIds ID of an actual savepoint
3502 * @param AtomicSectionIdentifier|null $newSectionId New top section ID.
3503 * @throws UnexpectedValueException
3505 private function modifyCallbacksForCancel(
3506 array $sectionIds, AtomicSectionIdentifier
$newSectionId = null
3508 // Cancel the "on commit" callbacks owned by this savepoint
3509 $this->trxIdleCallbacks
= array_filter(
3510 $this->trxIdleCallbacks
,
3511 function ( $entry ) use ( $sectionIds ) {
3512 return !in_array( $entry[2], $sectionIds, true );
3515 $this->trxPreCommitCallbacks
= array_filter(
3516 $this->trxPreCommitCallbacks
,
3517 function ( $entry ) use ( $sectionIds ) {
3518 return !in_array( $entry[2], $sectionIds, true );
3521 // Make "on resolution" callbacks owned by this savepoint to perceive a rollback
3522 foreach ( $this->trxEndCallbacks
as $key => $entry ) {
3523 if ( in_array( $entry[2], $sectionIds, true ) ) {
3524 $callback = $entry[0];
3525 $this->trxEndCallbacks
[$key][0] = function () use ( $callback ) {
3526 // @phan-suppress-next-line PhanInfiniteRecursion No recursion at all here, phan is confused
3527 return $callback( self
::TRIGGER_ROLLBACK
, $this );
3529 // This "on resolution" callback no longer belongs to a section.
3530 $this->trxEndCallbacks
[$key][2] = null;
3533 // Hoist callback ownership for section cancel callbacks to the new top section
3534 foreach ( $this->trxSectionCancelCallbacks
as $key => $entry ) {
3535 if ( in_array( $entry[2], $sectionIds, true ) ) {
3536 $this->trxSectionCancelCallbacks
[$key][2] = $newSectionId;
3541 final public function setTransactionListener( $name, callable
$callback = null ) {
3543 $this->trxRecurringCallbacks
[$name] = $callback;
3545 unset( $this->trxRecurringCallbacks
[$name] );
3550 * Whether to disable running of post-COMMIT/ROLLBACK callbacks
3552 * This method should not be used outside of Database/LoadBalancer
3554 * @param bool $suppress
3557 final public function setTrxEndCallbackSuppression( $suppress ) {
3558 $this->trxEndCallbacksSuppressed
= $suppress;
3562 * Actually consume and run any "on transaction idle/resolution" callbacks.
3564 * This method should not be used outside of Database/LoadBalancer
3566 * @param int $trigger IDatabase::TRIGGER_* constant
3567 * @return int Number of callbacks attempted
3571 public function runOnTransactionIdleCallbacks( $trigger ) {
3572 if ( $this->trxLevel() ) { // sanity
3573 throw new DBUnexpectedError( $this, __METHOD__
. ': a transaction is still open' );
3576 if ( $this->trxEndCallbacksSuppressed
) {
3581 $autoTrx = $this->getFlag( self
::DBO_TRX
); // automatic begin() enabled?
3582 /** @var Exception $e */
3583 $e = null; // first exception
3584 do { // callbacks may add callbacks :)
3585 $callbacks = array_merge(
3586 $this->trxIdleCallbacks
,
3587 $this->trxEndCallbacks
// include "transaction resolution" callbacks
3589 $this->trxIdleCallbacks
= []; // consumed (and recursion guard)
3590 $this->trxEndCallbacks
= []; // consumed (recursion guard)
3592 // Only run trxSectionCancelCallbacks on rollback, not commit.
3593 // But always consume them.
3594 if ( $trigger === self
::TRIGGER_ROLLBACK
) {
3595 $callbacks = array_merge( $callbacks, $this->trxSectionCancelCallbacks
);
3597 $this->trxSectionCancelCallbacks
= []; // consumed (recursion guard)
3599 foreach ( $callbacks as $callback ) {
3601 list( $phpCallback ) = $callback;
3602 $this->clearFlag( self
::DBO_TRX
); // make each query its own transaction
3604 // @phan-suppress-next-line PhanParamTooManyCallable
3605 call_user_func( $phpCallback, $trigger, $this );
3606 } catch ( Exception
$ex ) {
3607 call_user_func( $this->errorLogger
, $ex );
3609 // Some callbacks may use startAtomic/endAtomic, so make sure
3610 // their transactions are ended so other callbacks don't fail
3611 if ( $this->trxLevel() ) {
3612 $this->rollback( __METHOD__
, self
::FLUSHING_INTERNAL
);
3616 $this->setFlag( self
::DBO_TRX
); // restore automatic begin()
3618 $this->clearFlag( self
::DBO_TRX
); // restore auto-commit
3622 } while ( count( $this->trxIdleCallbacks
) );
3624 if ( $e instanceof Exception
) {
3625 throw $e; // re-throw any first exception
3632 * Actually consume and run any "on transaction pre-commit" callbacks.
3634 * This method should not be used outside of Database/LoadBalancer
3637 * @return int Number of callbacks attempted
3640 public function runOnTransactionPreCommitCallbacks() {
3643 $e = null; // first exception
3644 do { // callbacks may add callbacks :)
3645 $callbacks = $this->trxPreCommitCallbacks
;
3646 $this->trxPreCommitCallbacks
= []; // consumed (and recursion guard)
3647 foreach ( $callbacks as $callback ) {
3650 list( $phpCallback ) = $callback;
3651 $phpCallback( $this );
3652 } catch ( Exception
$ex ) {
3653 ( $this->errorLogger
)( $ex );
3657 } while ( count( $this->trxPreCommitCallbacks
) );
3659 if ( $e instanceof Exception
) {
3660 throw $e; // re-throw any first exception
3667 * Actually run any "atomic section cancel" callbacks.
3669 * @param int $trigger IDatabase::TRIGGER_* constant
3670 * @param AtomicSectionIdentifier[]|null $sectionIds Section IDs to cancel,
3671 * null on transaction rollback
3673 private function runOnAtomicSectionCancelCallbacks(
3674 $trigger, array $sectionIds = null
3676 /** @var Exception|Throwable $e */
3677 $e = null; // first exception
3681 $callbacks = $this->trxSectionCancelCallbacks
;
3682 $this->trxSectionCancelCallbacks
= []; // consumed (recursion guard)
3683 foreach ( $callbacks as $entry ) {
3684 if ( $sectionIds === null ||
in_array( $entry[2], $sectionIds, true ) ) {
3686 $entry[0]( $trigger, $this );
3687 } catch ( Exception
$ex ) {
3688 ( $this->errorLogger
)( $ex );
3690 } catch ( Throwable
$ex ) {
3695 $notCancelled[] = $entry;
3698 } while ( count( $this->trxSectionCancelCallbacks
) );
3699 $this->trxSectionCancelCallbacks
= $notCancelled;
3701 if ( $e !== null ) {
3702 throw $e; // re-throw any first Exception/Throwable
3707 * Actually run any "transaction listener" callbacks.
3709 * This method should not be used outside of Database/LoadBalancer
3711 * @param int $trigger IDatabase::TRIGGER_* constant
3715 public function runTransactionListenerCallbacks( $trigger ) {
3716 if ( $this->trxEndCallbacksSuppressed
) {
3720 /** @var Exception $e */
3721 $e = null; // first exception
3723 foreach ( $this->trxRecurringCallbacks
as $phpCallback ) {
3725 $phpCallback( $trigger, $this );
3726 } catch ( Exception
$ex ) {
3727 ( $this->errorLogger
)( $ex );
3732 if ( $e instanceof Exception
) {
3733 throw $e; // re-throw any first exception
3738 * Create a savepoint
3740 * This is used internally to implement atomic sections. It should not be
3744 * @param string $identifier Identifier for the savepoint
3745 * @param string $fname Calling function name
3747 protected function doSavepoint( $identifier, $fname ) {
3748 $this->query( 'SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3752 * Release a savepoint
3754 * This is used internally to implement atomic sections. It should not be
3758 * @param string $identifier Identifier for the savepoint
3759 * @param string $fname Calling function name
3761 protected function doReleaseSavepoint( $identifier, $fname ) {
3762 $this->query( 'RELEASE SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3766 * Rollback to a savepoint
3768 * This is used internally to implement atomic sections. It should not be
3772 * @param string $identifier Identifier for the savepoint
3773 * @param string $fname Calling function name
3775 protected function doRollbackToSavepoint( $identifier, $fname ) {
3776 $this->query( 'ROLLBACK TO SAVEPOINT ' . $this->addIdentifierQuotes( $identifier ), $fname );
3780 * @param string $fname
3783 private function nextSavepointId( $fname ) {
3784 $savepointId = self
::$SAVEPOINT_PREFIX . ++
$this->trxAtomicCounter
;
3785 if ( strlen( $savepointId ) > 30 ) {
3786 // 30 == Oracle's identifier length limit (pre 12c)
3787 // With a 22 character prefix, that puts the highest number at 99999999.
3788 throw new DBUnexpectedError(
3790 'There have been an excessively large number of atomic sections in a transaction'
3791 . " started by $this->trxFname (at $fname)"
3795 return $savepointId;
3798 final public function startAtomic(
3799 $fname = __METHOD__
, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3801 $savepointId = $cancelable === self
::ATOMIC_CANCELABLE ? self
::$NOT_APPLICABLE : null;
3803 if ( !$this->trxLevel() ) {
3804 $this->begin( $fname, self
::TRANSACTION_INTERNAL
); // sets trxAutomatic
3805 // If DBO_TRX is set, a series of startAtomic/endAtomic pairs will result
3806 // in all changes being in one transaction to keep requests transactional.
3807 if ( $this->getFlag( self
::DBO_TRX
) ) {
3808 // Since writes could happen in between the topmost atomic sections as part
3809 // of the transaction, those sections will need savepoints.
3810 $savepointId = $this->nextSavepointId( $fname );
3811 $this->doSavepoint( $savepointId, $fname );
3813 $this->trxAutomaticAtomic
= true;
3815 } elseif ( $cancelable === self
::ATOMIC_CANCELABLE
) {
3816 $savepointId = $this->nextSavepointId( $fname );
3817 $this->doSavepoint( $savepointId, $fname );
3820 $sectionId = new AtomicSectionIdentifier
;
3821 $this->trxAtomicLevels
[] = [ $fname, $sectionId, $savepointId ];
3822 $this->queryLogger
->debug( 'startAtomic: entering level ' .
3823 ( count( $this->trxAtomicLevels
) - 1 ) . " ($fname)" );
3828 final public function endAtomic( $fname = __METHOD__
) {
3829 if ( !$this->trxLevel() ||
!$this->trxAtomicLevels
) {
3830 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)" );
3833 // Check if the current section matches $fname
3834 $pos = count( $this->trxAtomicLevels
) - 1;
3835 list( $savedFname, $sectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3836 $this->queryLogger
->debug( "endAtomic: leaving level $pos ($fname)" );
3838 if ( $savedFname !== $fname ) {
3839 throw new DBUnexpectedError(
3841 "Invalid atomic section ended (got $fname but expected $savedFname)"
3845 // Remove the last section (no need to re-index the array)
3846 array_pop( $this->trxAtomicLevels
);
3848 if ( !$this->trxAtomicLevels
&& $this->trxAutomaticAtomic
) {
3849 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
3850 } elseif ( $savepointId !== null && $savepointId !== self
::$NOT_APPLICABLE ) {
3851 $this->doReleaseSavepoint( $savepointId, $fname );
3854 // Hoist callback ownership for callbacks in the section that just ended;
3855 // all callbacks should have an owner that is present in trxAtomicLevels.
3856 $currentSectionId = $this->currentAtomicSectionId();
3857 if ( $currentSectionId ) {
3858 $this->reassignCallbacksForSection( $sectionId, $currentSectionId );
3862 final public function cancelAtomic(
3863 $fname = __METHOD__
, AtomicSectionIdentifier
$sectionId = null
3865 if ( !$this->trxLevel() ||
!$this->trxAtomicLevels
) {
3866 throw new DBUnexpectedError( $this, "No atomic section is open (got $fname)" );
3870 $newTopSection = $this->currentAtomicSectionId();
3872 $excisedFnames = [];
3873 if ( $sectionId !== null ) {
3874 // Find the (last) section with the given $sectionId
3876 foreach ( $this->trxAtomicLevels
as $i => list( $asFname, $asId, $spId ) ) {
3877 if ( $asId === $sectionId ) {
3882 throw new DBUnexpectedError( $this, "Atomic section not found (for $fname)" );
3884 // Remove all descendant sections and re-index the array
3885 $len = count( $this->trxAtomicLevels
);
3886 for ( $i = $pos +
1; $i < $len; ++
$i ) {
3887 $excisedFnames[] = $this->trxAtomicLevels
[$i][0];
3888 $excisedIds[] = $this->trxAtomicLevels
[$i][1];
3890 $this->trxAtomicLevels
= array_slice( $this->trxAtomicLevels
, 0, $pos +
1 );
3891 $newTopSection = $this->currentAtomicSectionId();
3894 // Check if the current section matches $fname
3895 $pos = count( $this->trxAtomicLevels
) - 1;
3896 list( $savedFname, $savedSectionId, $savepointId ) = $this->trxAtomicLevels
[$pos];
3898 if ( $excisedFnames ) {
3899 $this->queryLogger
->debug( "cancelAtomic: canceling level $pos ($savedFname) " .
3900 "and descendants " . implode( ', ', $excisedFnames ) );
3902 $this->queryLogger
->debug( "cancelAtomic: canceling level $pos ($savedFname)" );
3905 if ( $savedFname !== $fname ) {
3906 throw new DBUnexpectedError(
3908 "Invalid atomic section ended (got $fname but expected $savedFname)"
3912 // Remove the last section (no need to re-index the array)
3913 array_pop( $this->trxAtomicLevels
);
3914 $excisedIds[] = $savedSectionId;
3915 $newTopSection = $this->currentAtomicSectionId();
3917 if ( $savepointId !== null ) {
3918 // Rollback the transaction to the state just before this atomic section
3919 if ( $savepointId === self
::$NOT_APPLICABLE ) {
3920 $this->rollback( $fname, self
::FLUSHING_INTERNAL
);
3921 // Note: rollback() will run trxSectionCancelCallbacks
3923 $this->doRollbackToSavepoint( $savepointId, $fname );
3924 $this->trxStatus
= self
::STATUS_TRX_OK
; // no exception; recovered
3925 $this->trxStatusIgnoredCause
= null;
3927 // Run trxSectionCancelCallbacks now.
3928 $this->runOnAtomicSectionCancelCallbacks( self
::TRIGGER_CANCEL
, $excisedIds );
3930 } elseif ( $this->trxStatus
> self
::STATUS_TRX_ERROR
) {
3931 // Put the transaction into an error state if it's not already in one
3932 $this->trxStatus
= self
::STATUS_TRX_ERROR
;
3933 $this->trxStatusCause
= new DBUnexpectedError(
3935 "Uncancelable atomic section canceled (got $fname)"
3939 // Fix up callbacks owned by the sections that were just cancelled.
3940 // All callbacks should have an owner that is present in trxAtomicLevels.
3941 $this->modifyCallbacksForCancel( $excisedIds, $newTopSection );
3944 $this->affectedRowCount
= 0; // for the sake of consistency
3947 final public function doAtomicSection(
3948 $fname, callable
$callback, $cancelable = self
::ATOMIC_NOT_CANCELABLE
3950 $sectionId = $this->startAtomic( $fname, $cancelable );
3952 $res = $callback( $this, $fname );
3953 } catch ( Exception
$e ) {
3954 $this->cancelAtomic( $fname, $sectionId );
3958 $this->endAtomic( $fname );
3963 final public function begin( $fname = __METHOD__
, $mode = self
::TRANSACTION_EXPLICIT
) {
3964 static $modes = [ self
::TRANSACTION_EXPLICIT
, self
::TRANSACTION_INTERNAL
];
3965 if ( !in_array( $mode, $modes, true ) ) {
3966 throw new DBUnexpectedError( $this, "$fname: invalid mode parameter '$mode'" );
3969 // Protect against mismatched atomic section, transaction nesting, and snapshot loss
3970 if ( $this->trxLevel() ) {
3971 if ( $this->trxAtomicLevels
) {
3972 $levels = $this->flatAtomicSectionList();
3973 $msg = "$fname: Got explicit BEGIN while atomic section(s) $levels are open";
3974 throw new DBUnexpectedError( $this, $msg );
3975 } elseif ( !$this->trxAutomatic
) {
3976 $msg = "$fname: Explicit transaction already active (from {$this->trxFname})";
3977 throw new DBUnexpectedError( $this, $msg );
3979 $msg = "$fname: Implicit transaction already active (from {$this->trxFname})";
3980 throw new DBUnexpectedError( $this, $msg );
3982 } elseif ( $this->getFlag( self
::DBO_TRX
) && $mode !== self
::TRANSACTION_INTERNAL
) {
3983 $msg = "$fname: Implicit transaction expected (DBO_TRX set)";
3984 throw new DBUnexpectedError( $this, $msg );
3987 $this->assertHasConnectionHandle();
3989 $this->doBegin( $fname );
3990 $this->trxShortId
= sprintf( '%06x', mt_rand( 0, 0xffffff ) );
3991 $this->trxStatus
= self
::STATUS_TRX_OK
;
3992 $this->trxStatusIgnoredCause
= null;
3993 $this->trxAtomicCounter
= 0;
3994 $this->trxTimestamp
= microtime( true );
3995 $this->trxFname
= $fname;
3996 $this->trxDoneWrites
= false;
3997 $this->trxAutomaticAtomic
= false;
3998 $this->trxAtomicLevels
= [];
3999 $this->trxWriteDuration
= 0.0;
4000 $this->trxWriteQueryCount
= 0;
4001 $this->trxWriteAffectedRows
= 0;
4002 $this->trxWriteAdjDuration
= 0.0;
4003 $this->trxWriteAdjQueryCount
= 0;
4004 $this->trxWriteCallers
= [];
4005 // First SELECT after BEGIN will establish the snapshot in REPEATABLE-READ.
4006 // Get an estimate of the replication lag before any such queries.
4007 $this->trxReplicaLag
= null; // clear cached value first
4008 $this->trxReplicaLag
= $this->getApproximateLagStatus()['lag'];
4009 // T147697: make explicitTrxActive() return true until begin() finishes. This way, no
4010 // caller will think its OK to muck around with the transaction just because startAtomic()
4011 // has not yet completed (e.g. setting trxAtomicLevels).
4012 $this->trxAutomatic
= ( $mode === self
::TRANSACTION_INTERNAL
);
4016 * Issues the BEGIN command to the database server.
4018 * @see Database::begin()
4019 * @param string $fname
4022 protected function doBegin( $fname ) {
4023 $this->query( 'BEGIN', $fname );
4026 final public function commit( $fname = __METHOD__
, $flush = self
::FLUSHING_ONE
) {
4027 static $modes = [ self
::FLUSHING_ONE
, self
::FLUSHING_ALL_PEERS
, self
::FLUSHING_INTERNAL
];
4028 if ( !in_array( $flush, $modes, true ) ) {
4029 throw new DBUnexpectedError( $this, "$fname: invalid flush parameter '$flush'" );
4032 if ( $this->trxLevel() && $this->trxAtomicLevels
) {
4033 // There are still atomic sections open; this cannot be ignored
4034 $levels = $this->flatAtomicSectionList();
4035 throw new DBUnexpectedError(
4037 "$fname: Got COMMIT while atomic sections $levels are still open"
4041 if ( $flush === self
::FLUSHING_INTERNAL ||
$flush === self
::FLUSHING_ALL_PEERS
) {
4042 if ( !$this->trxLevel() ) {
4043 return; // nothing to do
4044 } elseif ( !$this->trxAutomatic
) {
4045 throw new DBUnexpectedError(
4047 "$fname: Flushing an explicit transaction, getting out of sync"
4050 } elseif ( !$this->trxLevel() ) {
4051 $this->queryLogger
->error(
4052 "$fname: No transaction to commit, something got out of sync" );
4053 return; // nothing to do
4054 } elseif ( $this->trxAutomatic
) {
4055 throw new DBUnexpectedError(
4057 "$fname: Expected mass commit of all peer transactions (DBO_TRX set)"
4061 $this->assertHasConnectionHandle();
4063 $this->runOnTransactionPreCommitCallbacks();
4065 $writeTime = $this->pendingWriteQueryDuration( self
::ESTIMATE_DB_APPLY
);
4066 $this->doCommit( $fname );
4067 $oldTrxShortId = $this->consumeTrxShortId();
4068 $this->trxStatus
= self
::STATUS_TRX_NONE
;
4070 if ( $this->trxDoneWrites
) {
4071 $this->lastWriteTime
= microtime( true );
4072 $this->trxProfiler
->transactionWritingOut(
4074 $this->getDomainID(),
4077 $this->trxWriteAffectedRows
4081 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
4082 if ( $flush !== self
::FLUSHING_ALL_PEERS
) {
4083 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_COMMIT
);
4084 $this->runTransactionListenerCallbacks( self
::TRIGGER_COMMIT
);
4089 * Issues the COMMIT command to the database server.
4091 * @see Database::commit()
4092 * @param string $fname
4095 protected function doCommit( $fname ) {
4096 if ( $this->trxLevel() ) {
4097 $this->query( 'COMMIT', $fname );
4101 final public function rollback( $fname = __METHOD__
, $flush = self
::FLUSHING_ONE
) {
4102 $trxActive = $this->trxLevel();
4104 if ( $flush !== self
::FLUSHING_INTERNAL
4105 && $flush !== self
::FLUSHING_ALL_PEERS
4106 && $this->getFlag( self
::DBO_TRX
)
4108 throw new DBUnexpectedError(
4110 "$fname: Expected mass rollback of all peer transactions (DBO_TRX set)"
4115 $this->assertHasConnectionHandle();
4117 $this->doRollback( $fname );
4118 $oldTrxShortId = $this->consumeTrxShortId();
4119 $this->trxStatus
= self
::STATUS_TRX_NONE
;
4120 $this->trxAtomicLevels
= [];
4121 // Estimate the RTT via a query now that trxStatus is OK
4122 $writeTime = $this->pingAndCalculateLastTrxApplyTime();
4124 if ( $this->trxDoneWrites
) {
4125 $this->trxProfiler
->transactionWritingOut(
4127 $this->getDomainID(),
4130 $this->trxWriteAffectedRows
4135 // Clear any commit-dependant callbacks. They might even be present
4136 // only due to transaction rounds, with no SQL transaction being active
4137 $this->trxIdleCallbacks
= [];
4138 $this->trxPreCommitCallbacks
= [];
4140 // With FLUSHING_ALL_PEERS, callbacks will be explicitly run later
4141 if ( $trxActive && $flush !== self
::FLUSHING_ALL_PEERS
) {
4143 $this->runOnTransactionIdleCallbacks( self
::TRIGGER_ROLLBACK
);
4144 } catch ( Exception
$e ) {
4145 // already logged; finish and let LoadBalancer move on during mass-rollback
4148 $this->runTransactionListenerCallbacks( self
::TRIGGER_ROLLBACK
);
4149 } catch ( Exception
$e ) {
4150 // already logged; let LoadBalancer move on during mass-rollback
4153 $this->affectedRowCount
= 0; // for the sake of consistency
4158 * Issues the ROLLBACK command to the database server.
4160 * @see Database::rollback()
4161 * @param string $fname
4164 protected function doRollback( $fname ) {
4165 if ( $this->trxLevel() ) {
4166 # Disconnects cause rollback anyway, so ignore those errors
4167 $ignoreErrors = true;
4168 $this->query( 'ROLLBACK', $fname, $ignoreErrors );
4172 public function flushSnapshot( $fname = __METHOD__
, $flush = self
::FLUSHING_ONE
) {
4173 if ( $this->explicitTrxActive() ) {
4174 // Committing this transaction would break callers that assume it is still open
4175 throw new DBUnexpectedError(
4177 "$fname: Cannot flush snapshot; " .
4178 "explicit transaction '{$this->trxFname}' is still open"
4180 } elseif ( $this->writesOrCallbacksPending() ) {
4181 // This only flushes transactions to clear snapshots, not to write data
4182 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4183 throw new DBUnexpectedError(
4185 "$fname: Cannot flush snapshot; " .
4186 "writes from transaction {$this->trxFname} are still pending ($fnames)"
4189 $this->trxLevel() &&
4190 $this->getTransactionRoundId() &&
4191 $flush !== self
::FLUSHING_INTERNAL
&&
4192 $flush !== self
::FLUSHING_ALL_PEERS
4194 $this->queryLogger
->warning(
4195 "$fname: Expected mass snapshot flush of all peer transactions " .
4196 "in the explicit transactions round '{$this->getTransactionRoundId()}'",
4197 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
4201 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4204 public function explicitTrxActive() {
4205 return $this->trxLevel() && ( $this->trxAtomicLevels ||
!$this->trxAutomatic
);
4208 public function duplicateTableStructure(
4209 $oldName, $newName, $temporary = false, $fname = __METHOD__
4211 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4214 public function listTables( $prefix = null, $fname = __METHOD__
) {
4215 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4218 public function listViews( $prefix = null, $fname = __METHOD__
) {
4219 throw new RuntimeException( __METHOD__
. ' is not implemented in descendant class' );
4222 public function timestamp( $ts = 0 ) {
4223 $t = new ConvertibleTimestamp( $ts );
4224 // Let errors bubble up to avoid putting garbage in the DB
4225 return $t->getTimestamp( TS_MW
);
4228 public function timestampOrNull( $ts = null ) {
4229 if ( is_null( $ts ) ) {
4232 return $this->timestamp( $ts );
4236 public function affectedRows() {
4237 return ( $this->affectedRowCount
=== null )
4238 ?
$this->fetchAffectedRowCount() // default to driver value
4239 : $this->affectedRowCount
;
4243 * @return int Number of retrieved rows according to the driver
4245 abstract protected function fetchAffectedRowCount();
4248 * Take a query result and wrap it in an iterable result wrapper if necessary.
4249 * Booleans are passed through as-is to indicate success/failure of write queries.
4251 * Once upon a time, Database::query() returned a bare MySQL result
4252 * resource, and it was necessary to call this function to convert it to
4253 * a wrapper. Nowadays, raw database objects are never exposed to external
4254 * callers, so this is unnecessary in external code.
4256 * @param bool|IResultWrapper|resource $result
4257 * @return bool|IResultWrapper
4259 protected function resultObject( $result ) {
4261 return false; // failed query
4262 } elseif ( $result instanceof IResultWrapper
) {
4264 } elseif ( $result === true ) {
4265 return $result; // succesful write query
4267 return new ResultWrapper( $this, $result );
4271 public function ping( &$rtt = null ) {
4272 // Avoid hitting the server if it was hit recently
4273 if ( $this->isOpen() && ( microtime( true ) - $this->lastPing
) < self
::$PING_TTL ) {
4274 if ( !func_num_args() ||
$this->lastRoundTripEstimate
> 0 ) {
4275 $rtt = $this->lastRoundTripEstimate
;
4276 return true; // don't care about $rtt
4280 // This will reconnect if possible or return false if not
4281 $this->clearFlag( self
::DBO_TRX
, self
::REMEMBER_PRIOR
);
4282 $ok = ( $this->query( self
::$PING_QUERY, __METHOD__
, true ) !== false );
4283 $this->restoreFlags( self
::RESTORE_PRIOR
);
4286 $rtt = $this->lastRoundTripEstimate
;
4293 * Close any existing (dead) database connection and open a new connection
4295 * @param string $fname
4296 * @return bool True if new connection is opened successfully, false if error
4298 protected function replaceLostConnection( $fname ) {
4299 $this->closeConnection();
4300 $this->conn
= false;
4302 $this->handleSessionLossPreconnect();
4309 $this->currentDomain
->getDatabase(),
4310 $this->currentDomain
->getSchema(),
4311 $this->tablePrefix()
4313 $this->lastPing
= microtime( true );
4316 $this->connLogger
->warning(
4317 $fname . ': lost connection to {dbserver}; reconnected',
4319 'dbserver' => $this->getServer(),
4320 'trace' => ( new RuntimeException() )->getTraceAsString()
4323 } catch ( DBConnectionError
$e ) {
4326 $this->connLogger
->error(
4327 $fname . ': lost connection to {dbserver} permanently',
4328 [ 'dbserver' => $this->getServer() ]
4332 $this->handleSessionLossPostconnect();
4337 public function getSessionLagStatus() {
4338 return $this->getRecordedTransactionLagStatus() ?
: $this->getApproximateLagStatus();
4342 * Get the replica DB lag when the current transaction started
4344 * This is useful when transactions might use snapshot isolation
4345 * (e.g. REPEATABLE-READ in innodb), so the "real" lag of that data
4346 * is this lag plus transaction duration. If they don't, it is still
4347 * safe to be pessimistic. This returns null if there is no transaction.
4349 * This returns null if the lag status for this transaction was not yet recorded.
4351 * @return array|null ('lag': seconds or false on error, 'since': UNIX timestamp of BEGIN)
4354 final protected function getRecordedTransactionLagStatus() {
4355 return ( $this->trxLevel() && $this->trxReplicaLag
!== null )
4356 ?
[ 'lag' => $this->trxReplicaLag
, 'since' => $this->trxTimestamp() ]
4361 * Get a replica DB lag estimate for this server
4363 * @return array ('lag': seconds or false on error, 'since': UNIX timestamp of estimate)
4366 protected function getApproximateLagStatus() {
4368 'lag' => $this->getLBInfo( 'replica' ) ?
$this->getLag() : 0,
4369 'since' => microtime( true )
4374 * Merge the result of getSessionLagStatus() for several DBs
4375 * using the most pessimistic values to estimate the lag of
4376 * any data derived from them in combination
4378 * This is information is useful for caching modules
4380 * @see WANObjectCache::set()
4381 * @see WANObjectCache::getWithSetCallback()
4383 * @param IDatabase $db1
4384 * @param IDatabase|null $db2 [optional]
4385 * @return array Map of values:
4386 * - lag: highest lag of any of the DBs or false on error (e.g. replication stopped)
4387 * - since: oldest UNIX timestamp of any of the DB lag estimates
4388 * - pending: whether any of the DBs have uncommitted changes
4392 public static function getCacheSetOptions( IDatabase
$db1, IDatabase
$db2 = null ) {
4393 $res = [ 'lag' => 0, 'since' => INF
, 'pending' => false ];
4394 foreach ( func_get_args() as $db ) {
4395 /** @var IDatabase $db */
4396 $status = $db->getSessionLagStatus();
4397 if ( $status['lag'] === false ) {
4398 $res['lag'] = false;
4399 } elseif ( $res['lag'] !== false ) {
4400 $res['lag'] = max( $res['lag'], $status['lag'] );
4402 $res['since'] = min( $res['since'], $status['since'] );
4403 $res['pending'] = $res['pending'] ?
: $db->writesPending();
4409 public function getLag() {
4410 if ( $this->getLBInfo( 'master' ) ) {
4411 return 0; // this is the master
4412 } elseif ( $this->getLBInfo( 'is static' ) ) {
4413 return 0; // static dataset
4416 return $this->doGetLag();
4419 protected function doGetLag() {
4423 public function maxListLen() {
4427 public function encodeBlob( $b ) {
4431 public function decodeBlob( $b ) {
4432 if ( $b instanceof Blob
) {
4438 public function setSessionOptions( array $options ) {
4441 public function sourceFile(
4443 callable
$lineCallback = null,
4444 callable
$resultCallback = null,
4446 callable
$inputCallback = null
4448 AtEase
::suppressWarnings();
4449 $fp = fopen( $filename, 'r' );
4450 AtEase
::restoreWarnings();
4452 if ( $fp === false ) {
4453 throw new RuntimeException( "Could not open \"{$filename}\"" );
4457 $fname = __METHOD__
. "( $filename )";
4461 $error = $this->sourceStream(
4462 $fp, $lineCallback, $resultCallback, $fname, $inputCallback );
4463 } catch ( Exception
$e ) {
4473 public function setSchemaVars( $vars ) {
4474 $this->schemaVars
= $vars;
4477 public function sourceStream(
4479 callable
$lineCallback = null,
4480 callable
$resultCallback = null,
4481 $fname = __METHOD__
,
4482 callable
$inputCallback = null
4484 $delimiterReset = new ScopedCallback(
4485 function ( $delimiter ) {
4486 $this->delimiter
= $delimiter;
4488 [ $this->delimiter
]
4492 while ( !feof( $fp ) ) {
4493 if ( $lineCallback ) {
4494 call_user_func( $lineCallback );
4497 $line = trim( fgets( $fp ) );
4499 if ( $line == '' ) {
4503 if ( $line[0] == '-' && $line[1] == '-' ) {
4511 $done = $this->streamStatementEnd( $cmd, $line );
4515 if ( $done ||
feof( $fp ) ) {
4516 $cmd = $this->replaceVars( $cmd );
4518 if ( $inputCallback ) {
4519 $callbackResult = $inputCallback( $cmd );
4521 if ( is_string( $callbackResult ) ||
!$callbackResult ) {
4522 $cmd = $callbackResult;
4527 $res = $this->query( $cmd, $fname );
4529 if ( $resultCallback ) {
4530 $resultCallback( $res, $this );
4533 if ( $res === false ) {
4534 $err = $this->lastError();
4536 return "Query \"{$cmd}\" failed with error code \"$err\".\n";
4543 ScopedCallback
::consume( $delimiterReset );
4548 * Called by sourceStream() to check if we've reached a statement end
4550 * @param string &$sql SQL assembled so far
4551 * @param string &$newLine New line about to be added to $sql
4552 * @return bool Whether $newLine contains end of the statement
4554 public function streamStatementEnd( &$sql, &$newLine ) {
4555 if ( $this->delimiter
) {
4557 $newLine = preg_replace(
4558 '/' . preg_quote( $this->delimiter
, '/' ) . '$/', '', $newLine );
4559 if ( $newLine != $prev ) {
4568 * Database independent variable replacement. Replaces a set of variables
4569 * in an SQL statement with their contents as given by $this->getSchemaVars().
4571 * Supports '{$var}' `{$var}` and / *$var* / (without the spaces) style variables.
4573 * - '{$var}' should be used for text and is passed through the database's
4575 * - `{$var}` should be used for identifiers (e.g. table and database names).
4576 * It is passed through the database's addIdentifierQuotes method which
4577 * can be overridden if the database uses something other than backticks.
4578 * - / *_* / or / *$wgDBprefix* / passes the name that follows through the
4579 * database's tableName method.
4580 * - / *i* / passes the name that follows through the database's indexName method.
4581 * - In all other cases, / *$var* / is left unencoded. Except for table options,
4582 * its use should be avoided. In 1.24 and older, string encoding was applied.
4584 * @param string $ins SQL statement to replace variables in
4585 * @return string The new SQL statement with variables replaced
4587 protected function replaceVars( $ins ) {
4588 $vars = $this->getSchemaVars();
4589 return preg_replace_callback(
4591 /\* (\$wgDBprefix|[_i]) \*/ (\w*) | # 1-2. tableName, indexName
4592 \'\{\$ (\w+) }\' | # 3. addQuotes
4593 `\{\$ (\w+) }` | # 4. addIdentifierQuotes
4594 /\*\$ (\w+) \*/ # 5. leave unencoded
4596 function ( $m ) use ( $vars ) {
4597 // Note: Because of <https://bugs.php.net/bug.php?id=51881>,
4598 // check for both nonexistent keys *and* the empty string.
4599 if ( isset( $m[1] ) && $m[1] !== '' ) {
4600 if ( $m[1] === 'i' ) {
4601 return $this->indexName( $m[2] );
4603 return $this->tableName( $m[2] );
4605 } elseif ( isset( $m[3] ) && $m[3] !== '' && array_key_exists( $m[3], $vars ) ) {
4606 return $this->addQuotes( $vars[$m[3]] );
4607 } elseif ( isset( $m[4] ) && $m[4] !== '' && array_key_exists( $m[4], $vars ) ) {
4608 return $this->addIdentifierQuotes( $vars[$m[4]] );
4609 } elseif ( isset( $m[5] ) && $m[5] !== '' && array_key_exists( $m[5], $vars ) ) {
4610 return $vars[$m[5]];
4620 * Get schema variables. If none have been set via setSchemaVars(), then
4621 * use some defaults from the current object.
4625 protected function getSchemaVars() {
4626 if ( $this->schemaVars
) {
4627 return $this->schemaVars
;
4629 return $this->getDefaultSchemaVars();
4634 * Get schema variables to use if none have been set via setSchemaVars().
4636 * Override this in derived classes to provide variables for tables.sql
4637 * and SQL patch files.
4641 protected function getDefaultSchemaVars() {
4645 public function lockIsFree( $lockName, $method ) {
4646 // RDBMs methods for checking named locks may or may not count this thread itself.
4647 // In MySQL, IS_FREE_LOCK() returns 0 if the thread already has the lock. This is
4648 // the behavior choosen by the interface for this method.
4649 return !isset( $this->sessionNamedLocks
[$lockName] );
4652 public function lock( $lockName, $method, $timeout = 5 ) {
4653 $this->sessionNamedLocks
[$lockName] = 1;
4658 public function unlock( $lockName, $method ) {
4659 unset( $this->sessionNamedLocks
[$lockName] );
4664 public function getScopedLockAndFlush( $lockKey, $fname, $timeout ) {
4665 if ( $this->writesOrCallbacksPending() ) {
4666 // This only flushes transactions to clear snapshots, not to write data
4667 $fnames = implode( ', ', $this->pendingWriteAndCallbackCallers() );
4668 throw new DBUnexpectedError(
4670 "$fname: Cannot flush pre-lock snapshot; " .
4671 "writes from transaction {$this->trxFname} are still pending ($fnames)"
4675 if ( !$this->lock( $lockKey, $fname, $timeout ) ) {
4679 $unlocker = new ScopedCallback( function () use ( $lockKey, $fname ) {
4680 if ( $this->trxLevel() ) {
4681 // There is a good chance an exception was thrown, causing any early return
4682 // from the caller. Let any error handler get a chance to issue rollback().
4683 // If there isn't one, let the error bubble up and trigger server-side rollback.
4684 $this->onTransactionResolution(
4685 function () use ( $lockKey, $fname ) {
4686 $this->unlock( $lockKey, $fname );
4691 $this->unlock( $lockKey, $fname );
4695 $this->commit( $fname, self
::FLUSHING_INTERNAL
);
4700 public function namedLocksEnqueue() {
4704 public function tableLocksHaveTransactionScope() {
4708 final public function lockTables( array $read, array $write, $method ) {
4709 if ( $this->writesOrCallbacksPending() ) {
4710 throw new DBUnexpectedError( $this, "Transaction writes or callbacks still pending" );
4713 if ( $this->tableLocksHaveTransactionScope() ) {
4714 $this->startAtomic( $method );
4717 return $this->doLockTables( $read, $write, $method );
4721 * Helper function for lockTables() that handles the actual table locking
4723 * @param array $read Array of tables to lock for read access
4724 * @param array $write Array of tables to lock for write access
4725 * @param string $method Name of caller
4728 protected function doLockTables( array $read, array $write, $method ) {
4732 final public function unlockTables( $method ) {
4733 if ( $this->tableLocksHaveTransactionScope() ) {
4734 $this->endAtomic( $method );
4736 return true; // locks released on COMMIT/ROLLBACK
4739 return $this->doUnlockTables( $method );
4743 * Helper function for unlockTables() that handles the actual table unlocking
4745 * @param string $method Name of caller
4748 protected function doUnlockTables( $method ) {
4754 * @param string $tableName
4755 * @param string $fName
4756 * @return bool|IResultWrapper
4759 public function dropTable( $tableName, $fName = __METHOD__
) {
4760 if ( !$this->tableExists( $tableName, $fName ) ) {
4763 $sql = "DROP TABLE " . $this->tableName( $tableName ) . " CASCADE";
4765 return $this->query( $sql, $fName );
4768 public function getInfinity() {
4772 public function encodeExpiry( $expiry ) {
4773 return ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() )
4774 ?
$this->getInfinity()
4775 : $this->timestamp( $expiry );
4778 public function decodeExpiry( $expiry, $format = TS_MW
) {
4779 if ( $expiry == '' ||
$expiry == 'infinity' ||
$expiry == $this->getInfinity() ) {
4783 return ConvertibleTimestamp
::convert( $format, $expiry );
4786 public function setBigSelects( $value = true ) {
4790 public function isReadOnly() {
4791 return ( $this->getReadOnlyReason() !== false );
4795 * @return string|bool Reason this DB is read-only or false if it is not
4797 protected function getReadOnlyReason() {
4798 $reason = $this->getLBInfo( 'readOnlyReason' );
4799 if ( is_string( $reason ) ) {
4801 } elseif ( $this->getLBInfo( 'replica' ) ) {
4802 return "Server is configured in the role of a read-only replica database.";
4808 public function setTableAliases( array $aliases ) {
4809 $this->tableAliases
= $aliases;
4812 public function setIndexAliases( array $aliases ) {
4813 $this->indexAliases
= $aliases;
4821 protected function hasFlags( $field, $flags ) {
4822 return ( ( $field & $flags ) === $flags );
4826 * Get the underlying binding connection handle
4828 * Makes sure the connection resource is set (disconnects and ping() failure can unset it).
4829 * This catches broken callers than catch and ignore disconnection exceptions.
4830 * Unlike checking isOpen(), this is safe to call inside of open().
4833 * @throws DBUnexpectedError
4836 protected function getBindingHandle() {
4837 if ( !$this->conn
) {
4838 throw new DBUnexpectedError(
4840 'DB connection was already closed or the connection dropped'
4847 public function __toString() {
4848 // spl_object_id is PHP >= 7.2
4849 $id = function_exists( 'spl_object_id' )
4850 ?
spl_object_id( $this )
4851 : spl_object_hash( $this );
4853 $description = $this->getType() . ' object #' . $id;
4854 if ( is_resource( $this->conn
) ) {
4855 $description .= ' (' . (string)$this->conn
. ')'; // "resource id #<ID>"
4856 } elseif ( is_object( $this->conn
) ) {
4857 // spl_object_id is PHP >= 7.2
4858 $handleId = function_exists( 'spl_object_id' )
4859 ?
spl_object_id( $this->conn
)
4860 : spl_object_hash( $this->conn
);
4861 $description .= " (handle id #$handleId)";
4864 return $description;
4868 * Make sure that copies do not share the same client binding handle
4869 * @throws DBConnectionError
4871 public function __clone() {
4872 $this->connLogger
->warning(
4873 "Cloning " . static::class . " is not recommended; forking connection",
4874 [ 'trace' => ( new RuntimeException() )->getTraceAsString() ]
4877 if ( $this->isOpen() ) {
4878 // Open a new connection resource without messing with the old one
4879 $this->conn
= false;
4880 $this->trxEndCallbacks
= []; // don't copy
4881 $this->trxSectionCancelCallbacks
= []; // don't copy
4882 $this->handleSessionLossPreconnect(); // no trx or locks anymore
4887 $this->currentDomain
->getDatabase(),
4888 $this->currentDomain
->getSchema(),
4889 $this->tablePrefix()
4891 $this->lastPing
= microtime( true );
4896 * Called by serialize. Throw an exception when DB connection is serialized.
4897 * This causes problems on some database engines because the connection is
4898 * not restored on unserialize.
4900 public function __sleep() {
4901 throw new RuntimeException( 'Database serialization may cause problems, since ' .
4902 'the connection is not restored on wakeup' );
4906 * Run a few simple sanity checks and close dangling connections
4908 public function __destruct() {
4909 if ( $this->trxLevel() && $this->trxDoneWrites
) {
4910 trigger_error( "Uncommitted DB writes (transaction from {$this->trxFname})" );
4913 $danglingWriters = $this->pendingWriteAndCallbackCallers();
4914 if ( $danglingWriters ) {
4915 $fnames = implode( ', ', $danglingWriters );
4916 trigger_error( "DB transaction writes or callbacks still pending ($fnames)" );
4919 if ( $this->conn
) {
4920 // Avoid connection leaks for sanity. Normally, resources close at script completion.
4921 // The connection might already be closed in zend/hhvm by now, so suppress warnings.
4922 AtEase
::suppressWarnings();
4923 $this->closeConnection();
4924 AtEase
::restoreWarnings();
4931 * @deprecated since 1.28
4933 class_alias( Database
::class, 'DatabaseBase' );
4936 * @deprecated since 1.29
4938 class_alias( Database
::class, 'Database' );