3 * This is the MySQL database abstraction layer.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
18 * http://www.gnu.org/copyleft/gpl.html
23 namespace Wikimedia\Rdbms
;
28 use InvalidArgumentException
;
34 * Database abstraction object for MySQL.
35 * Defines methods independent on used MySQL extension.
41 abstract class DatabaseMysqlBase
extends Database
{
42 /** @var MysqlMasterPos */
43 protected $lastKnownReplicaPos;
44 /** @var string Method to detect replica DB lag */
45 protected $lagDetectionMethod;
46 /** @var array Method to detect replica DB lag */
47 protected $lagDetectionOptions = [];
48 /** @var bool bool Whether to use GTID methods */
49 protected $useGTIDs = false;
50 /** @var string|null */
51 protected $sslKeyPath;
52 /** @var string|null */
53 protected $sslCertPath;
54 /** @var string|null */
56 /** @var string|null */
58 /** @var string[]|null */
59 protected $sslCiphers;
60 /** @var string sql_mode value to send on connection */
62 /** @var bool Use experimental UTF-8 transmission encoding */
65 protected $defaultBigSelects = null;
67 /** @var string|null */
68 private $serverVersion = null;
70 private $insertSelectIsSafe = null;
71 /** @var stdClass|null */
72 private $replicationInfoRow = null;
74 // Cache getServerId() for 24 hours
75 const SERVER_ID_CACHE_TTL
= 86400;
77 /** @var float Warn if lag estimates are made for transactions older than this many seconds */
78 const LAG_STALE_WARN_THRESHOLD
= 0.100;
81 * Additional $params include:
82 * - lagDetectionMethod : set to one of (Seconds_Behind_Master,pt-heartbeat).
83 * pt-heartbeat assumes the table is at heartbeat.heartbeat
84 * and uses UTC timestamps in the heartbeat.ts column.
85 * (https://www.percona.com/doc/percona-toolkit/2.2/pt-heartbeat.html)
86 * - lagDetectionOptions : if using pt-heartbeat, this can be set to an array map to change
87 * the default behavior. Normally, the heartbeat row with the server
88 * ID of this server's master will be used. Set the "conds" field to
89 * override the query conditions, e.g. ['shard' => 's1'].
90 * - useGTIDs : use GTID methods like MASTER_GTID_WAIT() when possible.
91 * - insertSelectIsSafe : force that native INSERT SELECT is or is not safe [default: null]
92 * - sslKeyPath : path to key file [default: null]
93 * - sslCertPath : path to certificate file [default: null]
94 * - sslCAFile: path to a single certificate authority PEM file [default: null]
95 * - sslCAPath : parth to certificate authority PEM directory [default: null]
96 * - sslCiphers : array list of allowable ciphers [default: null]
97 * @param array $params
99 function __construct( array $params ) {
100 $this->lagDetectionMethod
= $params['lagDetectionMethod'] ??
'Seconds_Behind_Master';
101 $this->lagDetectionOptions
= $params['lagDetectionOptions'] ??
[];
102 $this->useGTIDs
= !empty( $params['useGTIDs' ] );
103 foreach ( [ 'KeyPath', 'CertPath', 'CAFile', 'CAPath', 'Ciphers' ] as $name ) {
105 if ( isset( $params[$var] ) ) {
106 $this->$var = $params[$var];
109 $this->sqlMode
= $params['sqlMode'] ??
null;
110 $this->utf8Mode
= !empty( $params['utf8Mode'] );
111 $this->insertSelectIsSafe
= isset( $params['insertSelectIsSafe'] )
112 ?
(bool)$params['insertSelectIsSafe'] : null;
114 parent
::__construct( $params );
120 public function getType() {
124 protected function open( $server, $user, $password, $dbName, $schema, $tablePrefix ) {
125 # Close/unset connection handle
128 $this->server
= $server;
130 $this->password
= $password;
132 $this->installErrorHandler();
134 $this->conn
= $this->mysqlConnect( $this->server
, $dbName );
135 } catch ( Exception
$ex ) {
136 $this->restoreErrorHandler();
139 $error = $this->restoreErrorHandler();
141 # Always log connection errors
142 if ( !$this->conn
) {
143 $error = $error ?
: $this->lastError();
144 $this->connLogger
->error(
145 "Error connecting to {db_server}: {error}",
146 $this->getLogContext( [
147 'method' => __METHOD__
,
151 $this->connLogger
->debug( "DB connection error\n" .
152 "Server: $server, User: $user, Password: " .
153 substr( $password, 0, 3 ) . "..., error: " . $error . "\n" );
155 throw new DBConnectionError( $this, $error );
158 if ( strlen( $dbName ) ) {
159 $this->selectDomain( new DatabaseDomain( $dbName, null, $tablePrefix ) );
161 $this->currentDomain
= new DatabaseDomain( null, null, $tablePrefix );
164 // Tell the server what we're communicating with
165 if ( !$this->connectInitCharset() ) {
166 $error = $this->lastError();
167 $this->queryLogger
->error(
168 "Error setting character set: {error}",
169 $this->getLogContext( [
170 'method' => __METHOD__
,
171 'error' => $this->lastError(),
174 throw new DBConnectionError( $this, "Error setting character set: $error" );
177 // Abstract over any insane MySQL defaults
178 $set = [ 'group_concat_max_len = 262144' ];
179 // Set SQL mode, default is turning them all off, can be overridden or skipped with null
180 if ( is_string( $this->sqlMode
) ) {
181 $set[] = 'sql_mode = ' . $this->addQuotes( $this->sqlMode
);
183 // Set any custom settings defined by site config
184 // (e.g. https://dev.mysql.com/doc/refman/4.1/en/innodb-parameters.html)
185 foreach ( $this->connectionVariables
as $var => $val ) {
186 // Escape strings but not numbers to avoid MySQL complaining
187 if ( !is_int( $val ) && !is_float( $val ) ) {
188 $val = $this->addQuotes( $val );
190 $set[] = $this->addIdentifierQuotes( $var ) . ' = ' . $val;
194 // Use doQuery() to avoid opening implicit transactions (DBO_TRX)
195 $success = $this->doQuery( 'SET ' . implode( ', ', $set ) );
197 $error = $this->lastError();
198 $this->queryLogger
->error(
199 'Error setting MySQL variables on server {db_server}: {error}',
200 $this->getLogContext( [
201 'method' => __METHOD__
,
205 throw new DBConnectionError( $this, "Error setting MySQL variables: $error" );
209 $this->opened
= true;
215 * Set the character set information right after connection
218 protected function connectInitCharset() {
219 if ( $this->utf8Mode
) {
220 // Tell the server we're communicating with it in UTF-8.
221 // This may engage various charset conversions.
222 return $this->mysqlSetCharset( 'utf8' );
224 return $this->mysqlSetCharset( 'binary' );
228 protected function doSelectDomain( DatabaseDomain
$domain ) {
229 if ( $domain->getSchema() !== null ) {
230 throw new DBExpectedError( $this, __CLASS__
. ": domain schemas are not supported." );
233 $database = $domain->getDatabase();
234 // A null database means "don't care" so leave it as is and update the table prefix
235 if ( $database === null ) {
236 $this->currentDomain
= new DatabaseDomain(
237 $this->currentDomain
->getDatabase(),
239 $domain->getTablePrefix()
245 if ( $database !== $this->getDBname() ) {
246 $sql = 'USE ' . $this->addIdentifierQuotes( $database );
247 list( $res, $err, $errno ) =
248 $this->executeQuery( $sql, __METHOD__
, self
::QUERY_IGNORE_DBO_TRX
);
250 if ( $res === false ) {
251 $this->reportQueryError( $err, $errno, $sql, __METHOD__
);
252 return false; // unreachable
256 // Update that domain fields on success (no exception thrown)
257 $this->currentDomain
= $domain;
263 * Open a connection to a MySQL server
265 * @param string $realServer
266 * @param string|null $dbName
267 * @return mixed Raw connection
268 * @throws DBConnectionError
270 abstract protected function mysqlConnect( $realServer, $dbName );
273 * Set the character set of the MySQL link
275 * @param string $charset
278 abstract protected function mysqlSetCharset( $charset );
281 * @param IResultWrapper|resource $res
282 * @throws DBUnexpectedError
284 public function freeResult( $res ) {
285 if ( $res instanceof ResultWrapper
) {
288 Wikimedia\
suppressWarnings();
289 $ok = $this->mysqlFreeResult( $res );
290 Wikimedia\restoreWarnings
();
292 throw new DBUnexpectedError( $this, "Unable to free MySQL result" );
299 * @param resource $res Raw result
302 abstract protected function mysqlFreeResult( $res );
305 * @param IResultWrapper|resource $res
306 * @return stdClass|bool
307 * @throws DBUnexpectedError
309 public function fetchObject( $res ) {
310 if ( $res instanceof ResultWrapper
) {
313 Wikimedia\
suppressWarnings();
314 $row = $this->mysqlFetchObject( $res );
315 Wikimedia\restoreWarnings
();
317 $errno = $this->lastErrno();
318 // Unfortunately, mysql_fetch_object does not reset the last errno.
319 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
320 // these are the only errors mysql_fetch_object can cause.
321 // See https://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
322 if ( $errno == 2000 ||
$errno == 2013 ) {
323 throw new DBUnexpectedError(
325 'Error in fetchObject(): ' . htmlspecialchars( $this->lastError() )
333 * Fetch a result row as an object
335 * @param resource $res Raw result
338 abstract protected function mysqlFetchObject( $res );
341 * @param IResultWrapper|resource $res
343 * @throws DBUnexpectedError
345 public function fetchRow( $res ) {
346 if ( $res instanceof ResultWrapper
) {
349 Wikimedia\
suppressWarnings();
350 $row = $this->mysqlFetchArray( $res );
351 Wikimedia\restoreWarnings
();
353 $errno = $this->lastErrno();
354 // Unfortunately, mysql_fetch_array does not reset the last errno.
355 // Only check for CR_SERVER_LOST and CR_UNKNOWN_ERROR, as
356 // these are the only errors mysql_fetch_array can cause.
357 // See https://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
358 if ( $errno == 2000 ||
$errno == 2013 ) {
359 throw new DBUnexpectedError(
361 'Error in fetchRow(): ' . htmlspecialchars( $this->lastError() )
369 * Fetch a result row as an associative and numeric array
371 * @param resource $res Raw result
372 * @return array|false
374 abstract protected function mysqlFetchArray( $res );
377 * @throws DBUnexpectedError
378 * @param IResultWrapper|resource $res
381 function numRows( $res ) {
382 if ( $res instanceof ResultWrapper
) {
385 Wikimedia\
suppressWarnings();
386 $n = !is_bool( $res ) ?
$this->mysqlNumRows( $res ) : 0;
387 Wikimedia\restoreWarnings
();
389 // Unfortunately, mysql_num_rows does not reset the last errno.
390 // We are not checking for any errors here, since
391 // there are no errors mysql_num_rows can cause.
392 // See https://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html.
393 // See https://phabricator.wikimedia.org/T44430
398 * Get number of rows in result
400 * @param resource $res Raw result
403 abstract protected function mysqlNumRows( $res );
406 * @param IResultWrapper|resource $res
409 public function numFields( $res ) {
410 if ( $res instanceof ResultWrapper
) {
414 return $this->mysqlNumFields( $res );
418 * Get number of fields in result
420 * @param resource $res Raw result
423 abstract protected function mysqlNumFields( $res );
426 * @param IResultWrapper|resource $res
430 public function fieldName( $res, $n ) {
431 if ( $res instanceof ResultWrapper
) {
435 return $this->mysqlFieldName( $res, $n );
439 * Get the name of the specified field in a result
441 * @param IResultWrapper|resource $res
445 abstract protected function mysqlFieldName( $res, $n );
448 * mysql_field_type() wrapper
449 * @param IResultWrapper|resource $res
453 public function fieldType( $res, $n ) {
454 if ( $res instanceof ResultWrapper
) {
458 return $this->mysqlFieldType( $res, $n );
462 * Get the type of the specified field in a result
464 * @param IResultWrapper|resource $res
468 abstract protected function mysqlFieldType( $res, $n );
471 * @param IResultWrapper|resource $res
475 public function dataSeek( $res, $row ) {
476 if ( $res instanceof ResultWrapper
) {
480 return $this->mysqlDataSeek( $res, $row );
484 * Move internal result pointer
486 * @param IResultWrapper|resource $res
490 abstract protected function mysqlDataSeek( $res, $row );
495 public function lastError() {
497 # Even if it's non-zero, it can still be invalid
498 Wikimedia\
suppressWarnings();
499 $error = $this->mysqlError( $this->conn
);
501 $error = $this->mysqlError();
503 Wikimedia\restoreWarnings
();
505 $error = $this->mysqlError();
508 $error .= ' (' . $this->server
. ')';
515 * Returns the text of the error message from previous MySQL operation
517 * @param resource|null $conn Raw connection
520 abstract protected function mysqlError( $conn = null );
522 protected function wasQueryTimeout( $error, $errno ) {
523 // https://dev.mysql.com/doc/refman/8.0/en/client-error-reference.html
524 // https://phabricator.wikimedia.org/T170638
525 return in_array( $errno, [ 2062, 3024 ] );
528 public function replace( $table, $uniqueIndexes, $rows, $fname = __METHOD__
) {
529 $this->nativeReplace( $table, $rows, $fname );
532 protected function isInsertSelectSafe( array $insertOptions, array $selectOptions ) {
533 $row = $this->getReplicationSafetyInfo();
534 // For row-based-replication, the resulting changes will be relayed, not the query
535 if ( $row->binlog_format
=== 'ROW' ) {
538 // LIMIT requires ORDER BY on a unique key or it is non-deterministic
539 if ( isset( $selectOptions['LIMIT'] ) ) {
542 // In MySQL, an INSERT SELECT is only replication safe with row-based
543 // replication or if innodb_autoinc_lock_mode is 0. When those
544 // conditions aren't met, use non-native mode.
545 // While we could try to determine if the insert is safe anyway by
546 // checking if the target table has an auto-increment column that
547 // isn't set in $varMap, that seems unlikely to be worth the extra
550 in_array( 'NO_AUTO_COLUMNS', $insertOptions ) ||
551 (int)$row->innodb_autoinc_lock_mode
=== 0
556 * @return stdClass Process cached row
558 protected function getReplicationSafetyInfo() {
559 if ( $this->replicationInfoRow
=== null ) {
560 $this->replicationInfoRow
= $this->selectRow(
563 'innodb_autoinc_lock_mode' => '@@innodb_autoinc_lock_mode',
564 'binlog_format' => '@@binlog_format',
571 return $this->replicationInfoRow
;
575 * Estimate rows in dataset
576 * Returns estimated count, based on EXPLAIN output
577 * Takes same arguments as Database::select()
579 * @param string|array $table
580 * @param string|array $var
581 * @param string|array $conds
582 * @param string $fname
583 * @param string|array $options
584 * @param array $join_conds
587 public function estimateRowCount( $table, $var = '*', $conds = '',
588 $fname = __METHOD__
, $options = [], $join_conds = []
590 $conds = $this->normalizeConditions( $conds, $fname );
591 $column = $this->extractSingleFieldFromList( $var );
592 if ( is_string( $column ) && !in_array( $column, [ '*', '1' ] ) ) {
593 $conds[] = "$column IS NOT NULL";
596 $options['EXPLAIN'] = true;
597 $res = $this->select( $table, $var, $conds, $fname, $options, $join_conds );
598 if ( $res === false ) {
601 if ( !$this->numRows( $res ) ) {
606 foreach ( $res as $plan ) {
607 $rows *= $plan->rows
> 0 ?
$plan->rows
: 1; // avoid resetting to zero
613 public function tableExists( $table, $fname = __METHOD__
) {
614 // Split database and table into proper variables as Database::tableName() returns
615 // shared tables prefixed with their database, which do not work in SHOW TABLES statements
616 list( $database, , $prefix, $table ) = $this->qualifiedTableComponents( $table );
617 $tableName = "{$prefix}{$table}";
619 if ( isset( $this->sessionTempTables
[$tableName] ) ) {
620 return true; // already known to exist and won't show in SHOW TABLES anyway
623 // We can't use buildLike() here, because it specifies an escape character
624 // other than the backslash, which is the only one supported by SHOW TABLES
625 $encLike = $this->escapeLikeInternal( $tableName, '\\' );
627 // If the database has been specified (such as for shared tables), use "FROM"
628 if ( $database !== '' ) {
629 $encDatabase = $this->addIdentifierQuotes( $database );
630 $query = "SHOW TABLES FROM $encDatabase LIKE '$encLike'";
632 $query = "SHOW TABLES LIKE '$encLike'";
635 return $this->query( $query, $fname )->numRows() > 0;
639 * @param string $table
640 * @param string $field
641 * @return bool|MySQLField
643 public function fieldInfo( $table, $field ) {
644 $table = $this->tableName( $table );
645 $res = $this->query( "SELECT * FROM $table LIMIT 1", __METHOD__
, true );
649 $n = $this->mysqlNumFields( $res->result
);
650 for ( $i = 0; $i < $n; $i++
) {
651 $meta = $this->mysqlFetchField( $res->result
, $i );
652 if ( $field == $meta->name
) {
653 return new MySQLField( $meta );
661 * Get column information from a result
663 * @param resource $res Raw result
667 abstract protected function mysqlFetchField( $res, $n );
670 * Get information about an index into an object
671 * Returns false if the index does not exist
673 * @param string $table
674 * @param string $index
675 * @param string $fname
676 * @return bool|array|null False or null on failure
678 public function indexInfo( $table, $index, $fname = __METHOD__
) {
679 # SHOW INDEX works in MySQL 3.23.58, but SHOW INDEXES does not.
680 # SHOW INDEX should work for 3.x and up:
681 # https://dev.mysql.com/doc/mysql/en/SHOW_INDEX.html
682 $table = $this->tableName( $table );
683 $index = $this->indexName( $index );
685 $sql = 'SHOW INDEX FROM ' . $table;
686 $res = $this->query( $sql, $fname );
694 foreach ( $res as $row ) {
695 if ( $row->Key_name
== $index ) {
700 return $result ?
: false;
707 public function strencode( $s ) {
708 return $this->mysqlRealEscapeString( $s );
715 abstract protected function mysqlRealEscapeString( $s );
717 public function addQuotes( $s ) {
718 if ( is_bool( $s ) ) {
719 // Parent would transform to int, which does not play nice with MySQL type juggling.
720 // When searching for an int in a string column, the strings are cast to int, which
721 // means false would match any string not starting with a number.
722 $s = (string)(int)$s;
724 return parent
::addQuotes( $s );
728 * MySQL uses `backticks` for identifier quoting instead of the sql standard "double quotes".
733 public function addIdentifierQuotes( $s ) {
734 // Characters in the range \u0001-\uFFFF are valid in a quoted identifier
735 // Remove NUL bytes and escape backticks by doubling
736 return '`' . str_replace( [ "\0", '`' ], [ '', '``' ], $s ) . '`';
740 * @param string $name
743 public function isQuotedIdentifier( $name ) {
744 return strlen( $name ) && $name[0] == '`' && substr( $name, -1, 1 ) == '`';
747 protected function doGetLag() {
748 if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
749 return $this->getLagFromPtHeartbeat();
751 return $this->getLagFromSlaveStatus();
758 protected function getLagDetectionMethod() {
759 return $this->lagDetectionMethod
;
765 protected function getLagFromSlaveStatus() {
766 $res = $this->query( 'SHOW SLAVE STATUS', __METHOD__
);
767 $row = $res ?
$res->fetchObject() : false;
768 // If the server is not replicating, there will be no row
769 if ( $row && strval( $row->Seconds_Behind_Master
) !== '' ) {
770 return intval( $row->Seconds_Behind_Master
);
779 protected function getLagFromPtHeartbeat() {
780 $options = $this->lagDetectionOptions
;
782 $currentTrxInfo = $this->getRecordedTransactionLagStatus();
783 if ( $currentTrxInfo ) {
784 // There is an active transaction and the initial lag was already queried
785 $staleness = microtime( true ) - $currentTrxInfo['since'];
786 if ( $staleness > self
::LAG_STALE_WARN_THRESHOLD
) {
787 // Avoid returning higher and higher lag value due to snapshot age
788 // given that the isolation level will typically be REPEATABLE-READ
789 $this->queryLogger
->warning(
790 "Using cached lag value for {db_server} due to active transaction",
791 $this->getLogContext( [
792 'method' => __METHOD__
,
794 'trace' => ( new RuntimeException() )->getTraceAsString()
799 return $currentTrxInfo['lag'];
802 if ( isset( $options['conds'] ) ) {
803 // Best method for multi-DC setups: use logical channel names
804 $data = $this->getHeartbeatData( $options['conds'] );
806 // Standard method: use master server ID (works with stock pt-heartbeat)
807 $masterInfo = $this->getMasterServerInfo();
808 if ( !$masterInfo ) {
809 $this->queryLogger
->error(
810 "Unable to query master of {db_server} for server ID",
811 $this->getLogContext( [
812 'method' => __METHOD__
816 return false; // could not get master server ID
819 $conds = [ 'server_id' => intval( $masterInfo['serverId'] ) ];
820 $data = $this->getHeartbeatData( $conds );
823 list( $time, $nowUnix ) = $data;
824 if ( $time !== null ) {
825 // @time is in ISO format like "2015-09-25T16:48:10.000510"
826 $dateTime = new DateTime( $time, new DateTimeZone( 'UTC' ) );
827 $timeUnix = (int)$dateTime->format( 'U' ) +
$dateTime->format( 'u' ) / 1e6
;
829 return max( $nowUnix - $timeUnix, 0.0 );
832 $this->queryLogger
->error(
833 "Unable to find pt-heartbeat row for {db_server}",
834 $this->getLogContext( [
835 'method' => __METHOD__
842 protected function getMasterServerInfo() {
843 $cache = $this->srvCache
;
844 $key = $cache->makeGlobalKey(
847 // Using one key for all cluster replica DBs is preferable
848 $this->getLBInfo( 'clusterMasterHost' ) ?
: $this->getServer()
852 return $cache->getWithSetCallback(
854 $cache::TTL_INDEFINITE
,
855 function () use ( $cache, $key, $fname ) {
856 // Get and leave a lock key in place for a short period
857 if ( !$cache->lock( $key, 0, 10 ) ) {
858 return false; // avoid master connection spike slams
861 $conn = $this->getLazyMasterHandle();
863 return false; // something is misconfigured
866 // Connect to and query the master; catch errors to avoid outages
868 $res = $conn->query( 'SELECT @@server_id AS id', $fname );
869 $row = $res ?
$res->fetchObject() : false;
870 $id = $row ?
(int)$row->id
: 0;
871 } catch ( DBError
$e ) {
875 // Cache the ID if it was retrieved
876 return $id ?
[ 'serverId' => $id, 'asOf' => time() ] : false;
882 * @param array $conds WHERE clause conditions to find a row
883 * @return array (heartbeat `ts` column value or null, UNIX timestamp) for the newest beat
884 * @see https://www.percona.com/doc/percona-toolkit/2.1/pt-heartbeat.html
886 protected function getHeartbeatData( array $conds ) {
887 // Query time and trip time are not counted
888 $nowUnix = microtime( true );
889 // Do not bother starting implicit transactions here
890 $this->clearFlag( self
::DBO_TRX
, self
::REMEMBER_PRIOR
);
892 $whereSQL = $this->makeList( $conds, self
::LIST_AND
);
893 // Use ORDER BY for channel based queries since that field might not be UNIQUE.
894 // Note: this would use "TIMESTAMPDIFF(MICROSECOND,ts,UTC_TIMESTAMP(6))" but the
895 // percision field is not supported in MySQL <= 5.5.
897 "SELECT ts FROM heartbeat.heartbeat WHERE $whereSQL ORDER BY ts DESC LIMIT 1",
900 $row = $res ?
$res->fetchObject() : false;
902 $this->restoreFlags();
905 return [ $row ?
$row->ts
: null, $nowUnix ];
908 protected function getApproximateLagStatus() {
909 if ( $this->getLagDetectionMethod() === 'pt-heartbeat' ) {
910 // Disable caching since this is fast enough and we don't wan't
911 // to be *too* pessimistic by having both the cache TTL and the
912 // pt-heartbeat interval count as lag in getSessionLagStatus()
913 return parent
::getApproximateLagStatus();
916 $key = $this->srvCache
->makeGlobalKey( 'mysql-lag', $this->getServer() );
917 $approxLag = $this->srvCache
->get( $key );
919 $approxLag = parent
::getApproximateLagStatus();
920 $this->srvCache
->set( $key, $approxLag, 1 );
926 public function masterPosWait( DBMasterPos
$pos, $timeout ) {
927 if ( !( $pos instanceof MySQLMasterPos
) ) {
928 throw new InvalidArgumentException( "Position not an instance of MySQLMasterPos" );
931 if ( $this->getLBInfo( 'is static' ) === true ) {
932 return 0; // this is a copy of a read-only dataset with no master DB
933 } elseif ( $this->lastKnownReplicaPos
&& $this->lastKnownReplicaPos
->hasReached( $pos ) ) {
934 return 0; // already reached this point for sure
937 // Call doQuery() directly, to avoid opening a transaction if DBO_TRX is set
938 if ( $pos->getGTIDs() ) {
939 // Ignore GTIDs from domains exclusive to the master DB (presumably inactive)
940 $rpos = $this->getReplicaPos();
941 $gtidsWait = $rpos ? MySQLMasterPos
::getCommonDomainGTIDs( $pos, $rpos ) : [];
943 $this->queryLogger
->error(
944 "No GTIDs with the same domain between master ($pos) and replica ($rpos)",
945 $this->getLogContext( [
946 'method' => __METHOD__
,
950 return -1; // $pos is from the wrong cluster?
952 // Wait on the GTID set (MariaDB only)
953 $gtidArg = $this->addQuotes( implode( ',', $gtidsWait ) );
954 if ( strpos( $gtidArg, ':' ) !== false ) {
955 // MySQL GTIDs, e.g "source_id:transaction_id"
956 $sql = "SELECT WAIT_FOR_EXECUTED_GTID_SET($gtidArg, $timeout)";
958 // MariaDB GTIDs, e.g."domain:server:sequence"
959 $sql = "SELECT MASTER_GTID_WAIT($gtidArg, $timeout)";
962 // Wait on the binlog coordinates
963 $encFile = $this->addQuotes( $pos->getLogFile() );
964 $encPos = intval( $pos->getLogPosition()[$pos::CORD_EVENT
] );
965 $sql = "SELECT MASTER_POS_WAIT($encFile, $encPos, $timeout)";
968 list( $res, $err ) = $this->executeQuery( $sql, __METHOD__
, self
::QUERY_IGNORE_DBO_TRX
);
969 $row = $res ?
$this->fetchRow( $res ) : false;
971 throw new DBExpectedError( $this, "Replication wait failed: {$err}" );
974 // Result can be NULL (error), -1 (timeout), or 0+ per the MySQL manual
975 $status = ( $row[0] !== null ) ?
intval( $row[0] ) : null;
976 if ( $status === null ) {
977 if ( !$pos->getGTIDs() ) {
978 // T126436: jobs programmed to wait on master positions might be referencing
979 // binlogs with an old master hostname; this makes MASTER_POS_WAIT() return null.
980 // Try to detect this case and treat the replica DB as having reached the given
981 // position (any master switchover already requires that the new master be caught
982 // up before the switch).
983 $replicationPos = $this->getReplicaPos();
984 if ( $replicationPos && !$replicationPos->channelsMatch( $pos ) ) {
985 $this->lastKnownReplicaPos
= $replicationPos;
989 } elseif ( $status >= 0 ) {
990 // Remember that this position was reached to save queries next time
991 $this->lastKnownReplicaPos
= $pos;
998 * Get the position of the master from SHOW SLAVE STATUS
1000 * @return MySQLMasterPos|bool
1002 public function getReplicaPos() {
1003 $now = microtime( true ); // as-of-time *before* fetching GTID variables
1005 if ( $this->useGTIDs() ) {
1006 // Try to use GTIDs, fallbacking to binlog positions if not possible
1007 $data = $this->getServerGTIDs( __METHOD__
);
1008 // Use gtid_slave_pos for MariaDB and gtid_executed for MySQL
1009 foreach ( [ 'gtid_slave_pos', 'gtid_executed' ] as $name ) {
1010 if ( isset( $data[$name] ) && strlen( $data[$name] ) ) {
1011 return new MySQLMasterPos( $data[$name], $now );
1016 $data = $this->getServerRoleStatus( 'SLAVE', __METHOD__
);
1017 if ( $data && strlen( $data['Relay_Master_Log_File'] ) ) {
1018 return new MySQLMasterPos(
1019 "{$data['Relay_Master_Log_File']}/{$data['Exec_Master_Log_Pos']}",
1028 * Get the position of the master from SHOW MASTER STATUS
1030 * @return MySQLMasterPos|bool
1032 public function getMasterPos() {
1033 $now = microtime( true ); // as-of-time *before* fetching GTID variables
1036 if ( $this->useGTIDs() ) {
1037 // Try to use GTIDs, fallbacking to binlog positions if not possible
1038 $data = $this->getServerGTIDs( __METHOD__
);
1039 // Use gtid_binlog_pos for MariaDB and gtid_executed for MySQL
1040 foreach ( [ 'gtid_binlog_pos', 'gtid_executed' ] as $name ) {
1041 if ( isset( $data[$name] ) && strlen( $data[$name] ) ) {
1042 $pos = new MySQLMasterPos( $data[$name], $now );
1046 // Filter domains that are inactive or not relevant to the session
1048 $pos->setActiveOriginServerId( $this->getServerId() );
1049 $pos->setActiveOriginServerUUID( $this->getServerUUID() );
1050 if ( isset( $data['gtid_domain_id'] ) ) {
1051 $pos->setActiveDomain( $data['gtid_domain_id'] );
1057 $data = $this->getServerRoleStatus( 'MASTER', __METHOD__
);
1058 if ( $data && strlen( $data['File'] ) ) {
1059 $pos = new MySQLMasterPos( "{$data['File']}/{$data['Position']}", $now );
1068 * @throws DBQueryError If the variable doesn't exist for some reason
1070 protected function getServerId() {
1071 $fname = __METHOD__
;
1072 return $this->srvCache
->getWithSetCallback(
1073 $this->srvCache
->makeGlobalKey( 'mysql-server-id', $this->getServer() ),
1074 self
::SERVER_ID_CACHE_TTL
,
1075 function () use ( $fname ) {
1076 $res = $this->query( "SELECT @@server_id AS id", $fname );
1077 return intval( $this->fetchObject( $res )->id
);
1083 * @return string|null
1085 protected function getServerUUID() {
1086 return $this->srvCache
->getWithSetCallback(
1087 $this->srvCache
->makeGlobalKey( 'mysql-server-uuid', $this->getServer() ),
1088 self
::SERVER_ID_CACHE_TTL
,
1090 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'server_uuid'" );
1091 $row = $this->fetchObject( $res );
1093 return $row ?
$row->Value
: null;
1099 * @param string $fname
1102 protected function getServerGTIDs( $fname = __METHOD__
) {
1104 // Get global-only variables like gtid_executed
1105 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'gtid_%'", $fname );
1106 foreach ( $res as $row ) {
1107 $map[$row->Variable_name
] = $row->Value
;
1109 // Get session-specific (e.g. gtid_domain_id since that is were writes will log)
1110 $res = $this->query( "SHOW SESSION VARIABLES LIKE 'gtid_%'", $fname );
1111 foreach ( $res as $row ) {
1112 $map[$row->Variable_name
] = $row->Value
;
1119 * @param string $role One of "MASTER"/"SLAVE"
1120 * @param string $fname
1121 * @return string[] Latest available server status row
1123 protected function getServerRoleStatus( $role, $fname = __METHOD__
) {
1124 return $this->query( "SHOW $role STATUS", $fname )->fetchRow() ?
: [];
1127 public function serverIsReadOnly() {
1128 $res = $this->query( "SHOW GLOBAL VARIABLES LIKE 'read_only'", __METHOD__
);
1129 $row = $this->fetchObject( $res );
1131 return $row ?
( strtolower( $row->Value
) === 'on' ) : false;
1135 * @param string $index
1138 function useIndexClause( $index ) {
1139 return "FORCE INDEX (" . $this->indexName( $index ) . ")";
1143 * @param string $index
1146 function ignoreIndexClause( $index ) {
1147 return "IGNORE INDEX (" . $this->indexName( $index ) . ")";
1153 function lowPriorityOption() {
1154 return 'LOW_PRIORITY';
1160 public function getSoftwareLink() {
1161 // MariaDB includes its name in its version string; this is how MariaDB's version of
1162 // the mysql command-line client identifies MariaDB servers (see mariadb_connection()
1163 // in libmysql/libmysql.c).
1164 $version = $this->getServerVersion();
1165 if ( strpos( $version, 'MariaDB' ) !== false ||
strpos( $version, '-maria-' ) !== false ) {
1166 return '[{{int:version-db-mariadb-url}} MariaDB]';
1169 // Percona Server's version suffix is not very distinctive, and @@version_comment
1170 // doesn't give the necessary info for source builds, so assume the server is MySQL.
1171 // (Even Percona's version of mysql doesn't try to make the distinction.)
1172 return '[{{int:version-db-mysql-url}} MySQL]';
1178 public function getServerVersion() {
1179 // Not using mysql_get_server_info() or similar for consistency: in the handshake,
1180 // MariaDB 10 adds the prefix "5.5.5-", and only some newer client libraries strip
1181 // it off (see RPL_VERSION_HACK in include/mysql_com.h).
1182 if ( $this->serverVersion
=== null ) {
1183 $this->serverVersion
= $this->selectField( '', 'VERSION()', '', __METHOD__
);
1185 return $this->serverVersion
;
1189 * @param array $options
1191 public function setSessionOptions( array $options ) {
1192 if ( isset( $options['connTimeout'] ) ) {
1193 $timeout = (int)$options['connTimeout'];
1194 $this->query( "SET net_read_timeout=$timeout" );
1195 $this->query( "SET net_write_timeout=$timeout" );
1200 * @param string &$sql
1201 * @param string &$newLine
1204 public function streamStatementEnd( &$sql, &$newLine ) {
1205 if ( strtoupper( substr( $newLine, 0, 9 ) ) == 'DELIMITER' ) {
1206 preg_match( '/^DELIMITER\s+(\S+)/', $newLine, $m );
1207 $this->delimiter
= $m[1];
1211 return parent
::streamStatementEnd( $sql, $newLine );
1215 * Check to see if a named lock is available. This is non-blocking.
1217 * @param string $lockName Name of lock to poll
1218 * @param string $method Name of method calling us
1222 public function lockIsFree( $lockName, $method ) {
1223 if ( !parent
::lockIsFree( $lockName, $method ) ) {
1224 return false; // already held
1227 $encName = $this->addQuotes( $this->makeLockName( $lockName ) );
1228 $result = $this->query( "SELECT IS_FREE_LOCK($encName) AS lockstatus", $method );
1229 $row = $this->fetchObject( $result );
1231 return ( $row->lockstatus
== 1 );
1235 * @param string $lockName
1236 * @param string $method
1237 * @param int $timeout
1240 public function lock( $lockName, $method, $timeout = 5 ) {
1241 $encName = $this->addQuotes( $this->makeLockName( $lockName ) );
1242 $result = $this->query( "SELECT GET_LOCK($encName, $timeout) AS lockstatus", $method );
1243 $row = $this->fetchObject( $result );
1245 if ( $row->lockstatus
== 1 ) {
1246 parent
::lock( $lockName, $method, $timeout ); // record
1250 $this->queryLogger
->info( __METHOD__
. " failed to acquire lock '{lockname}'",
1251 [ 'lockname' => $lockName ] );
1258 * https://dev.mysql.com/doc/refman/5.0/en/miscellaneous-functions.html#function_release-lock
1259 * @param string $lockName
1260 * @param string $method
1263 public function unlock( $lockName, $method ) {
1264 $encName = $this->addQuotes( $this->makeLockName( $lockName ) );
1265 $result = $this->query( "SELECT RELEASE_LOCK($encName) as lockstatus", $method );
1266 $row = $this->fetchObject( $result );
1268 if ( $row->lockstatus
== 1 ) {
1269 parent
::unlock( $lockName, $method ); // record
1273 $this->queryLogger
->warning( __METHOD__
. " failed to release lock '$lockName'\n" );
1278 private function makeLockName( $lockName ) {
1279 // https://dev.mysql.com/doc/refman/5.7/en/miscellaneous-functions.html#function_get-lock
1280 // Newer version enforce a 64 char length limit.
1281 return ( strlen( $lockName ) > 64 ) ?
sha1( $lockName ) : $lockName;
1284 public function namedLocksEnqueue() {
1288 public function tableLocksHaveTransactionScope() {
1289 return false; // tied to TCP connection
1292 protected function doLockTables( array $read, array $write, $method ) {
1294 foreach ( $write as $table ) {
1295 $items[] = $this->tableName( $table ) . ' WRITE';
1297 foreach ( $read as $table ) {
1298 $items[] = $this->tableName( $table ) . ' READ';
1301 $sql = "LOCK TABLES " . implode( ',', $items );
1302 $this->query( $sql, $method );
1307 protected function doUnlockTables( $method ) {
1308 $this->query( "UNLOCK TABLES", $method );
1314 * @param bool $value
1316 public function setBigSelects( $value = true ) {
1317 if ( $value === 'default' ) {
1318 if ( $this->defaultBigSelects
=== null ) {
1319 # Function hasn't been called before so it must already be set to the default
1322 $value = $this->defaultBigSelects
;
1324 } elseif ( $this->defaultBigSelects
=== null ) {
1325 $this->defaultBigSelects
=
1326 (bool)$this->selectField( false, '@@sql_big_selects', '', __METHOD__
);
1328 $encValue = $value ?
'1' : '0';
1329 $this->query( "SET sql_big_selects=$encValue", __METHOD__
);
1333 * DELETE where the condition is a join. MySql uses multi-table deletes.
1334 * @param string $delTable
1335 * @param string $joinTable
1336 * @param string $delVar
1337 * @param string $joinVar
1338 * @param array|string $conds
1339 * @param bool|string $fname
1340 * @throws DBUnexpectedError
1342 public function deleteJoin(
1343 $delTable, $joinTable, $delVar, $joinVar, $conds, $fname = __METHOD__
1346 throw new DBUnexpectedError( $this, __METHOD__
. ' called with empty $conds' );
1349 $delTable = $this->tableName( $delTable );
1350 $joinTable = $this->tableName( $joinTable );
1351 $sql = "DELETE $delTable FROM $delTable, $joinTable WHERE $delVar=$joinVar ";
1353 if ( $conds != '*' ) {
1354 $sql .= ' AND ' . $this->makeList( $conds, self
::LIST_AND
);
1357 $this->query( $sql, $fname );
1360 public function upsert(
1361 $table, array $rows, $uniqueIndexes, array $set, $fname = __METHOD__
1363 if ( $rows === [] ) {
1364 return true; // nothing to do
1367 if ( !is_array( reset( $rows ) ) ) {
1371 $table = $this->tableName( $table );
1372 $columns = array_keys( $rows[0] );
1374 $sql = "INSERT INTO $table (" . implode( ',', $columns ) . ') VALUES ';
1376 foreach ( $rows as $row ) {
1377 $rowTuples[] = '(' . $this->makeList( $row ) . ')';
1379 $sql .= implode( ',', $rowTuples );
1380 $sql .= " ON DUPLICATE KEY UPDATE " . $this->makeList( $set, self
::LIST_SET
);
1382 $this->query( $sql, $fname );
1388 * Determines how long the server has been up
1392 public function getServerUptime() {
1393 $vars = $this->getMysqlStatus( 'Uptime' );
1395 return (int)$vars['Uptime'];
1399 * Determines if the last failure was due to a deadlock
1403 public function wasDeadlock() {
1404 return $this->lastErrno() == 1213;
1408 * Determines if the last failure was due to a lock timeout
1412 public function wasLockTimeout() {
1413 return $this->lastErrno() == 1205;
1417 * Determines if the last failure was due to the database being read-only.
1421 public function wasReadOnlyError() {
1422 return $this->lastErrno() == 1223 ||
1423 ( $this->lastErrno() == 1290 && strpos( $this->lastError(), '--read-only' ) !== false );
1426 public function wasConnectionError( $errno ) {
1427 return $errno == 2013 ||
$errno == 2006;
1430 protected function wasKnownStatementRollbackError() {
1431 $errno = $this->lastErrno();
1433 if ( $errno === 1205 ) { // lock wait timeout
1434 // Note that this is uncached to avoid stale values of SET is used
1435 $row = $this->selectRow(
1437 [ 'innodb_rollback_on_timeout' => '@@innodb_rollback_on_timeout' ],
1441 // https://dev.mysql.com/doc/refman/5.7/en/innodb-error-handling.html
1442 // https://dev.mysql.com/doc/refman/5.5/en/innodb-parameters.html
1443 return $row->innodb_rollback_on_timeout ?
false : true;
1446 // See https://dev.mysql.com/doc/refman/5.5/en/error-messages-server.html
1447 return in_array( $errno, [ 1022, 1062, 1216, 1217, 1137, 1146, 1051, 1054 ], true );
1451 * @param string $oldName
1452 * @param string $newName
1453 * @param bool $temporary
1454 * @param string $fname
1457 public function duplicateTableStructure(
1458 $oldName, $newName, $temporary = false, $fname = __METHOD__
1460 $tmp = $temporary ?
'TEMPORARY ' : '';
1461 $newName = $this->addIdentifierQuotes( $newName );
1462 $oldName = $this->addIdentifierQuotes( $oldName );
1463 $query = "CREATE $tmp TABLE $newName (LIKE $oldName)";
1465 return $this->query( $query, $fname, $this::QUERY_PSEUDO_PERMANENT
);
1469 * List all tables on the database
1471 * @param string|null $prefix Only show tables with this prefix, e.g. mw_
1472 * @param string $fname Calling function name
1475 public function listTables( $prefix = null, $fname = __METHOD__
) {
1476 $result = $this->query( "SHOW TABLES", $fname );
1480 foreach ( $result as $table ) {
1481 $vars = get_object_vars( $table );
1482 $table = array_pop( $vars );
1484 if ( !$prefix ||
strpos( $table, $prefix ) === 0 ) {
1485 $endArray[] = $table;
1493 * @param string $tableName
1494 * @param string $fName
1495 * @return bool|IResultWrapper
1497 public function dropTable( $tableName, $fName = __METHOD__
) {
1498 if ( !$this->tableExists( $tableName, $fName ) ) {
1502 return $this->query( "DROP TABLE IF EXISTS " . $this->tableName( $tableName ), $fName );
1506 * Get status information from SHOW STATUS in an associative array
1508 * @param string $which
1511 private function getMysqlStatus( $which = "%" ) {
1512 $res = $this->query( "SHOW STATUS LIKE '{$which}'" );
1515 foreach ( $res as $row ) {
1516 $status[$row->Variable_name
] = $row->Value
;
1523 * Lists VIEWs in the database
1525 * @param string|null $prefix Only show VIEWs with this prefix, eg.
1526 * unit_test_, or $wgDBprefix. Default: null, would return all views.
1527 * @param string $fname Name of calling function
1531 public function listViews( $prefix = null, $fname = __METHOD__
) {
1532 // The name of the column containing the name of the VIEW
1533 $propertyName = 'Tables_in_' . $this->getDBname();
1535 // Query for the VIEWS
1536 $res = $this->query( 'SHOW FULL TABLES WHERE TABLE_TYPE = "VIEW"' );
1538 foreach ( $res as $row ) {
1539 array_push( $allViews, $row->$propertyName );
1542 if ( is_null( $prefix ) ||
$prefix === '' ) {
1546 $filteredViews = [];
1547 foreach ( $allViews as $viewName ) {
1548 // Does the name of this VIEW start with the table-prefix?
1549 if ( strpos( $viewName, $prefix ) === 0 ) {
1550 array_push( $filteredViews, $viewName );
1554 return $filteredViews;
1558 * Differentiates between a TABLE and a VIEW.
1560 * @param string $name Name of the TABLE/VIEW to test
1561 * @param string|null $prefix
1565 public function isView( $name, $prefix = null ) {
1566 return in_array( $name, $this->listViews( $prefix ) );
1569 protected function isTransactableQuery( $sql ) {
1570 return parent
::isTransactableQuery( $sql ) &&
1571 !preg_match( '/^SELECT\s+(GET|RELEASE|IS_FREE)_LOCK\(/', $sql );
1574 public function buildStringCast( $field ) {
1575 return "CAST( $field AS BINARY )";
1579 * @param string $field Field or column to cast
1582 public function buildIntegerCast( $field ) {
1583 return 'CAST( ' . $field . ' AS SIGNED )';
1587 * @return bool Whether GTID support is used (mockable for testing)
1589 protected function useGTIDs() {
1590 return $this->useGTIDs
;
1595 * @deprecated since 1.29
1597 class_alias( DatabaseMysqlBase
::class, 'DatabaseMysqlBase' );