--- /dev/null
+<?php
+/**
+ * This is the Postgres database abstraction layer.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup Database
+ */
+namespace Wikimedia\Rdbms;
+
+use Wikimedia\Timestamp\ConvertibleTimestamp;
+use Wikimedia\WaitConditionLoop;
+use MediaWiki;
+use Exception;
+
+/**
+ * @ingroup Database
+ */
+class DatabasePostgres extends Database {
+ /** @var int|bool */
+ protected $port;
+
+ /** @var resource */
+ protected $mLastResult = null;
+ /** @var int The number of rows affected as an integer */
+ protected $mAffectedRows = null;
+
+ /** @var float|string */
+ private $numericVersion = null;
+ /** @var string Connect string to open a PostgreSQL connection */
+ private $connectString;
+ /** @var string */
+ private $mCoreSchema;
+ /** @var string[] Map of (reserved table name => alternate table name) */
+ private $keywordTableMap = [];
+
+ /**
+ * @see Database::__construct()
+ * @param array $params Additional parameters include:
+ * - keywordTableMap : Map of reserved table names to alternative table names to use
+ */
+ public function __construct( array $params ) {
+ $this->port = isset( $params['port'] ) ? $params['port'] : false;
+ $this->keywordTableMap = isset( $params['keywordTableMap'] )
+ ? $params['keywordTableMap']
+ : [];
+
+ parent::__construct( $params );
+ }
+
+ public function getType() {
+ return 'postgres';
+ }
+
+ public function implicitGroupby() {
+ return false;
+ }
+
+ public function implicitOrderby() {
+ return false;
+ }
+
+ public function hasConstraint( $name ) {
+ $conn = $this->getBindingHandle();
+
+ $sql = "SELECT 1 FROM pg_catalog.pg_constraint c, pg_catalog.pg_namespace n " .
+ "WHERE c.connamespace = n.oid AND conname = '" .
+ pg_escape_string( $conn, $name ) . "' AND n.nspname = '" .
+ pg_escape_string( $conn, $this->getCoreSchema() ) . "'";
+ $res = $this->doQuery( $sql );
+
+ return $this->numRows( $res );
+ }
+
+ public function open( $server, $user, $password, $dbName ) {
+ # Test for Postgres support, to avoid suppressed fatal error
+ if ( !function_exists( 'pg_connect' ) ) {
+ throw new DBConnectionError(
+ $this,
+ "Postgres functions missing, have you compiled PHP with the --with-pgsql\n" .
+ "option? (Note: if you recently installed PHP, you may need to restart your\n" .
+ "webserver and database)\n"
+ );
+ }
+
+ $this->mServer = $server;
+ $this->mUser = $user;
+ $this->mPassword = $password;
+ $this->mDBname = $dbName;
+
+ $connectVars = [
+ // pg_connect() user $user as the default database. Since a database is *required*,
+ // at least pick a "don't care" database that is more likely to exist. This case
+ // arrises when LoadBalancer::getConnection( $i, [], '' ) is used.
+ 'dbname' => strlen( $dbName ) ? $dbName : 'postgres',
+ 'user' => $user,
+ 'password' => $password
+ ];
+ if ( $server != false && $server != '' ) {
+ $connectVars['host'] = $server;
+ }
+ if ( (int)$this->port > 0 ) {
+ $connectVars['port'] = (int)$this->port;
+ }
+ if ( $this->mFlags & self::DBO_SSL ) {
+ $connectVars['sslmode'] = 1;
+ }
+
+ $this->connectString = $this->makeConnectionString( $connectVars );
+ $this->close();
+ $this->installErrorHandler();
+
+ try {
+ // Use new connections to let LoadBalancer/LBFactory handle reuse
+ $this->mConn = pg_connect( $this->connectString, PGSQL_CONNECT_FORCE_NEW );
+ } catch ( Exception $ex ) {
+ $this->restoreErrorHandler();
+ throw $ex;
+ }
+
+ $phpError = $this->restoreErrorHandler();
+
+ if ( !$this->mConn ) {
+ $this->queryLogger->debug(
+ "DB connection error\n" .
+ "Server: $server, Database: $dbName, User: $user, Password: " .
+ substr( $password, 0, 3 ) . "...\n"
+ );
+ $this->queryLogger->debug( $this->lastError() . "\n" );
+ throw new DBConnectionError( $this, str_replace( "\n", ' ', $phpError ) );
+ }
+
+ $this->mOpened = true;
+
+ # If called from the command-line (e.g. importDump), only show errors
+ if ( $this->cliMode ) {
+ $this->doQuery( "SET client_min_messages = 'ERROR'" );
+ }
+
+ $this->query( "SET client_encoding='UTF8'", __METHOD__ );
+ $this->query( "SET datestyle = 'ISO, YMD'", __METHOD__ );
+ $this->query( "SET timezone = 'GMT'", __METHOD__ );
+ $this->query( "SET standard_conforming_strings = on", __METHOD__ );
+ if ( $this->getServerVersion() >= 9.0 ) {
+ $this->query( "SET bytea_output = 'escape'", __METHOD__ ); // PHP bug 53127
+ }
+
+ $this->determineCoreSchema( $this->mSchema );
+ // The schema to be used is now in the search path; no need for explicit qualification
+ $this->mSchema = '';
+
+ return $this->mConn;
+ }
+
+ public function databasesAreIndependent() {
+ return true;
+ }
+
+ /**
+ * Postgres doesn't support selectDB in the same way MySQL does. So if the
+ * DB name doesn't match the open connection, open a new one
+ * @param string $db
+ * @return bool
+ * @throws DBUnexpectedError
+ */
+ public function selectDB( $db ) {
+ if ( $this->mDBname !== $db ) {
+ return (bool)$this->open( $this->mServer, $this->mUser, $this->mPassword, $db );
+ } else {
+ return true;
+ }
+ }
+
+ /**
+ * @param string[] $vars
+ * @return string
+ */
+ private function makeConnectionString( $vars ) {
+ $s = '';
+ foreach ( $vars as $name => $value ) {
+ $s .= "$name='" . str_replace( "'", "\\'", $value ) . "' ";
+ }
+
+ return $s;
+ }
+
+ protected function closeConnection() {
+ return $this->mConn ? pg_close( $this->mConn ) : true;
+ }
+
+ public function doQuery( $sql ) {
+ $conn = $this->getBindingHandle();
+
+ $sql = mb_convert_encoding( $sql, 'UTF-8' );
+ // Clear previously left over PQresult
+ while ( $res = pg_get_result( $conn ) ) {
+ pg_free_result( $res );
+ }
+ if ( pg_send_query( $conn, $sql ) === false ) {
+ throw new DBUnexpectedError( $this, "Unable to post new query to PostgreSQL\n" );
+ }
+ $this->mLastResult = pg_get_result( $conn );
+ $this->mAffectedRows = null;
+ if ( pg_result_error( $this->mLastResult ) ) {
+ return false;
+ }
+
+ return $this->mLastResult;
+ }
+
+ protected function dumpError() {
+ $diags = [
+ PGSQL_DIAG_SEVERITY,
+ PGSQL_DIAG_SQLSTATE,
+ PGSQL_DIAG_MESSAGE_PRIMARY,
+ PGSQL_DIAG_MESSAGE_DETAIL,
+ PGSQL_DIAG_MESSAGE_HINT,
+ PGSQL_DIAG_STATEMENT_POSITION,
+ PGSQL_DIAG_INTERNAL_POSITION,
+ PGSQL_DIAG_INTERNAL_QUERY,
+ PGSQL_DIAG_CONTEXT,
+ PGSQL_DIAG_SOURCE_FILE,
+ PGSQL_DIAG_SOURCE_LINE,
+ PGSQL_DIAG_SOURCE_FUNCTION
+ ];
+ foreach ( $diags as $d ) {
+ $this->queryLogger->debug( sprintf( "PgSQL ERROR(%d): %s\n",
+ $d, pg_result_error_field( $this->mLastResult, $d ) ) );
+ }
+ }
+
+ public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
+ if ( $tempIgnore ) {
+ /* Check for constraint violation */
+ if ( $errno === '23505' ) {
+ parent::reportQueryError( $error, $errno, $sql, $fname, $tempIgnore );
+
+ return;
+ }
+ }
+ /* Transaction stays in the ERROR state until rolled back */
+ if ( $this->mTrxLevel ) {
+ // Throw away the transaction state, then raise the error as normal.
+ // Note that if this connection is managed by LBFactory, it's already expected
+ // that the other transactions LBFactory manages will be rolled back.
+ $this->rollback( __METHOD__, self::FLUSHING_INTERNAL );
+ }
+ parent::reportQueryError( $error, $errno, $sql, $fname, false );
+ }
+
+ public function freeResult( $res ) {
+ if ( $res instanceof ResultWrapper ) {
+ $res = $res->result;
+ }
+ MediaWiki\suppressWarnings();
+ $ok = pg_free_result( $res );
+ MediaWiki\restoreWarnings();
+ if ( !$ok ) {
+ throw new DBUnexpectedError( $this, "Unable to free Postgres result\n" );
+ }
+ }
+
+ public function fetchObject( $res ) {
+ if ( $res instanceof ResultWrapper ) {
+ $res = $res->result;
+ }
+ MediaWiki\suppressWarnings();
+ $row = pg_fetch_object( $res );
+ MediaWiki\restoreWarnings();
+ # @todo FIXME: HACK HACK HACK HACK debug
+
+ # @todo hashar: not sure if the following test really trigger if the object
+ # fetching failed.
+ $conn = $this->getBindingHandle();
+ if ( pg_last_error( $conn ) ) {
+ throw new DBUnexpectedError(
+ $this,
+ 'SQL error: ' . htmlspecialchars( pg_last_error( $conn ) )
+ );
+ }
+
+ return $row;
+ }
+
+ public function fetchRow( $res ) {
+ if ( $res instanceof ResultWrapper ) {
+ $res = $res->result;
+ }
+ MediaWiki\suppressWarnings();
+ $row = pg_fetch_array( $res );
+ MediaWiki\restoreWarnings();
+
+ $conn = $this->getBindingHandle();
+ if ( pg_last_error( $conn ) ) {
+ throw new DBUnexpectedError(
+ $this,
+ 'SQL error: ' . htmlspecialchars( pg_last_error( $conn ) )
+ );
+ }
+
+ return $row;
+ }
+
+ public function numRows( $res ) {
+ if ( $res instanceof ResultWrapper ) {
+ $res = $res->result;
+ }
+ MediaWiki\suppressWarnings();
+ $n = pg_num_rows( $res );
+ MediaWiki\restoreWarnings();
+
+ $conn = $this->getBindingHandle();
+ if ( pg_last_error( $conn ) ) {
+ throw new DBUnexpectedError(
+ $this,
+ 'SQL error: ' . htmlspecialchars( pg_last_error( $conn ) )
+ );
+ }
+
+ return $n;
+ }
+
+ public function numFields( $res ) {
+ if ( $res instanceof ResultWrapper ) {
+ $res = $res->result;
+ }
+
+ return pg_num_fields( $res );
+ }
+
+ public function fieldName( $res, $n ) {
+ if ( $res instanceof ResultWrapper ) {
+ $res = $res->result;
+ }
+
+ return pg_field_name( $res, $n );
+ }
+
+ public function insertId() {
+ $res = $this->query( "SELECT lastval()" );
+ $row = $this->fetchRow( $res );
+ return is_null( $row[0] ) ? null : (int)$row[0];
+ }
+
+ public function dataSeek( $res, $row ) {
+ if ( $res instanceof ResultWrapper ) {
+ $res = $res->result;
+ }
+
+ return pg_result_seek( $res, $row );
+ }
+
+ public function lastError() {
+ if ( $this->mConn ) {
+ if ( $this->mLastResult ) {
+ return pg_result_error( $this->mLastResult );
+ } else {
+ return pg_last_error();
+ }
+ }
+
+ return $this->getLastPHPError() ?: 'No database connection';
+ }
+
+ public function lastErrno() {
+ if ( $this->mLastResult ) {
+ return pg_result_error_field( $this->mLastResult, PGSQL_DIAG_SQLSTATE );
+ } else {
+ return false;
+ }
+ }
+
+ public function affectedRows() {
+ if ( !is_null( $this->mAffectedRows ) ) {
+ // Forced result for simulated queries
+ return $this->mAffectedRows;
+ }
+ if ( empty( $this->mLastResult ) ) {
+ return 0;
+ }
+
+ return pg_affected_rows( $this->mLastResult );
+ }
+
+ /**
+ * Estimate rows in dataset
+ * Returns estimated count, based on EXPLAIN output
+ * This is not necessarily an accurate estimate, so use sparingly
+ * Returns -1 if count cannot be found
+ * Takes same arguments as Database::select()
+ *
+ * @param string $table
+ * @param string $vars
+ * @param string $conds
+ * @param string $fname
+ * @param array $options
+ * @return int
+ */
+ public function estimateRowCount( $table, $vars = '*', $conds = '',
+ $fname = __METHOD__, $options = []
+ ) {
+ $options['EXPLAIN'] = true;
+ $res = $this->select( $table, $vars, $conds, $fname, $options );
+ $rows = -1;
+ if ( $res ) {
+ $row = $this->fetchRow( $res );
+ $count = [];
+ if ( preg_match( '/rows=(\d+)/', $row[0], $count ) ) {
+ $rows = (int)$count[1];
+ }
+ }
+
+ return $rows;
+ }
+
+ public function indexInfo( $table, $index, $fname = __METHOD__ ) {
+ $sql = "SELECT indexname FROM pg_indexes WHERE tablename='$table'";
+ $res = $this->query( $sql, $fname );
+ if ( !$res ) {
+ return null;
+ }
+ foreach ( $res as $row ) {
+ if ( $row->indexname == $this->indexName( $index ) ) {
+ return $row;
+ }
+ }
+
+ return false;
+ }
+
+ public function indexAttributes( $index, $schema = false ) {
+ if ( $schema === false ) {
+ $schema = $this->getCoreSchema();
+ }
+ /*
+ * A subquery would be not needed if we didn't care about the order
+ * of attributes, but we do
+ */
+ $sql = <<<__INDEXATTR__
+
+ SELECT opcname,
+ attname,
+ i.indoption[s.g] as option,
+ pg_am.amname
+ FROM
+ (SELECT generate_series(array_lower(isub.indkey,1), array_upper(isub.indkey,1)) AS g
+ FROM
+ pg_index isub
+ JOIN pg_class cis
+ ON cis.oid=isub.indexrelid
+ JOIN pg_namespace ns
+ ON cis.relnamespace = ns.oid
+ WHERE cis.relname='$index' AND ns.nspname='$schema') AS s,
+ pg_attribute,
+ pg_opclass opcls,
+ pg_am,
+ pg_class ci
+ JOIN pg_index i
+ ON ci.oid=i.indexrelid
+ JOIN pg_class ct
+ ON ct.oid = i.indrelid
+ JOIN pg_namespace n
+ ON ci.relnamespace = n.oid
+ WHERE
+ ci.relname='$index' AND n.nspname='$schema'
+ AND attrelid = ct.oid
+ AND i.indkey[s.g] = attnum
+ AND i.indclass[s.g] = opcls.oid
+ AND pg_am.oid = opcls.opcmethod
+__INDEXATTR__;
+ $res = $this->query( $sql, __METHOD__ );
+ $a = [];
+ if ( $res ) {
+ foreach ( $res as $row ) {
+ $a[] = [
+ $row->attname,
+ $row->opcname,
+ $row->amname,
+ $row->option ];
+ }
+ } else {
+ return null;
+ }
+
+ return $a;
+ }
+
+ public function indexUnique( $table, $index, $fname = __METHOD__ ) {
+ $sql = "SELECT indexname FROM pg_indexes WHERE tablename='{$table}'" .
+ " AND indexdef LIKE 'CREATE UNIQUE%(" .
+ $this->strencode( $this->indexName( $index ) ) .
+ ")'";
+ $res = $this->query( $sql, $fname );
+ if ( !$res ) {
+ return null;
+ }
+
+ return $res->numRows() > 0;
+ }
+
+ public function selectSQLText(
+ $table, $vars, $conds = '', $fname = __METHOD__, $options = [], $join_conds = []
+ ) {
+ if ( is_string( $options ) ) {
+ $options = [ $options ];
+ }
+
+ // Change the FOR UPDATE option as necessary based on the join conditions. Then pass
+ // to the parent function to get the actual SQL text.
+ // In Postgres when using FOR UPDATE, only the main table and tables that are inner joined
+ // can be locked. That means tables in an outer join cannot be FOR UPDATE locked. Trying to
+ // do so causes a DB error. This wrapper checks which tables can be locked and adjusts it
+ // accordingly.
+ // MySQL uses "ORDER BY NULL" as an optimization hint, but that is illegal in PostgreSQL.
+ if ( is_array( $options ) ) {
+ $forUpdateKey = array_search( 'FOR UPDATE', $options, true );
+ if ( $forUpdateKey !== false && $join_conds ) {
+ unset( $options[$forUpdateKey] );
+ $options['FOR UPDATE'] = [];
+
+ // All tables not in $join_conds are good
+ foreach ( $table as $alias => $name ) {
+ if ( is_numeric( $alias ) ) {
+ $alias = $name;
+ }
+ if ( !isset( $join_conds[$alias] ) ) {
+ $options['FOR UPDATE'][] = $alias;
+ }
+ }
+
+ foreach ( $join_conds as $table_cond => $join_cond ) {
+ if ( 0 === preg_match( '/^(?:LEFT|RIGHT|FULL)(?: OUTER)? JOIN$/i', $join_cond[0] ) ) {
+ $options['FOR UPDATE'][] = $table_cond;
+ }
+ }
+
+ // Quote alias names so $this->tableName() won't mangle them
+ $options['FOR UPDATE'] = array_map( function ( $name ) use ( $table ) {
+ return isset( $table[$name] ) ? $this->addIdentifierQuotes( $name ) : $name;
+ }, $options['FOR UPDATE'] );
+ }
+
+ if ( isset( $options['ORDER BY'] ) && $options['ORDER BY'] == 'NULL' ) {
+ unset( $options['ORDER BY'] );
+ }
+ }
+
+ return parent::selectSQLText( $table, $vars, $conds, $fname, $options, $join_conds );
+ }
+
+ /**
+ * INSERT wrapper, inserts an array into a table
+ *
+ * $args may be a single associative array, or an array of these with numeric keys,
+ * for multi-row insert (Postgres version 8.2 and above only).
+ *
+ * @param string $table Name of the table to insert to.
+ * @param array $args Items to insert into the table.
+ * @param string $fname Name of the function, for profiling
+ * @param array|string $options String or array. Valid options: IGNORE
+ * @return bool Success of insert operation. IGNORE always returns true.
+ */
+ public function insert( $table, $args, $fname = __METHOD__, $options = [] ) {
+ if ( !count( $args ) ) {
+ return true;
+ }
+
+ $table = $this->tableName( $table );
+ if ( !isset( $this->numericVersion ) ) {
+ $this->getServerVersion();
+ }
+
+ if ( !is_array( $options ) ) {
+ $options = [ $options ];
+ }
+
+ if ( isset( $args[0] ) && is_array( $args[0] ) ) {
+ $multi = true;
+ $keys = array_keys( $args[0] );
+ } else {
+ $multi = false;
+ $keys = array_keys( $args );
+ }
+
+ // If IGNORE is set, we use savepoints to emulate mysql's behavior
+ $savepoint = $olde = null;
+ $numrowsinserted = 0;
+ if ( in_array( 'IGNORE', $options ) ) {
+ $savepoint = new SavepointPostgres( $this, 'mw', $this->queryLogger );
+ $olde = error_reporting( 0 );
+ // For future use, we may want to track the number of actual inserts
+ // Right now, insert (all writes) simply return true/false
+ }
+
+ $sql = "INSERT INTO $table (" . implode( ',', $keys ) . ') VALUES ';
+
+ if ( $multi ) {
+ if ( $this->numericVersion >= 8.2 && !$savepoint ) {
+ $first = true;
+ foreach ( $args as $row ) {
+ if ( $first ) {
+ $first = false;
+ } else {
+ $sql .= ',';
+ }
+ $sql .= '(' . $this->makeList( $row ) . ')';
+ }
+ $res = (bool)$this->query( $sql, $fname, $savepoint );
+ } else {
+ $res = true;
+ $origsql = $sql;
+ foreach ( $args as $row ) {
+ $tempsql = $origsql;
+ $tempsql .= '(' . $this->makeList( $row ) . ')';
+
+ if ( $savepoint ) {
+ $savepoint->savepoint();
+ }
+
+ $tempres = (bool)$this->query( $tempsql, $fname, $savepoint );
+
+ if ( $savepoint ) {
+ $bar = pg_result_error( $this->mLastResult );
+ if ( $bar != false ) {
+ $savepoint->rollback();
+ } else {
+ $savepoint->release();
+ $numrowsinserted++;
+ }
+ }
+
+ // If any of them fail, we fail overall for this function call
+ // Note that this will be ignored if IGNORE is set
+ if ( !$tempres ) {
+ $res = false;
+ }
+ }
+ }
+ } else {
+ // Not multi, just a lone insert
+ if ( $savepoint ) {
+ $savepoint->savepoint();
+ }
+
+ $sql .= '(' . $this->makeList( $args ) . ')';
+ $res = (bool)$this->query( $sql, $fname, $savepoint );
+ if ( $savepoint ) {
+ $bar = pg_result_error( $this->mLastResult );
+ if ( $bar != false ) {
+ $savepoint->rollback();
+ } else {
+ $savepoint->release();
+ $numrowsinserted++;
+ }
+ }
+ }
+ if ( $savepoint ) {
+ error_reporting( $olde );
+ $savepoint->commit();
+
+ // Set the affected row count for the whole operation
+ $this->mAffectedRows = $numrowsinserted;
+
+ // IGNORE always returns true
+ return true;
+ }
+
+ return $res;
+ }
+
+ /**
+ * INSERT SELECT wrapper
+ * $varMap must be an associative array of the form [ 'dest1' => 'source1', ... ]
+ * Source items may be literals rather then field names, but strings should
+ * be quoted with Database::addQuotes()
+ * $conds may be "*" to copy the whole table
+ * srcTable may be an array of tables.
+ * @todo FIXME: Implement this a little better (seperate select/insert)?
+ *
+ * @param string $destTable
+ * @param array|string $srcTable
+ * @param array $varMap
+ * @param array $conds
+ * @param string $fname
+ * @param array $insertOptions
+ * @param array $selectOptions
+ * @param array $selectJoinConds
+ * @return bool
+ */
+ public function nativeInsertSelect(
+ $destTable, $srcTable, $varMap, $conds, $fname = __METHOD__,
+ $insertOptions = [], $selectOptions = [], $selectJoinConds = []
+ ) {
+ if ( !is_array( $insertOptions ) ) {
+ $insertOptions = [ $insertOptions ];
+ }
+
+ /*
+ * If IGNORE is set, we use savepoints to emulate mysql's behavior
+ * Ignore LOW PRIORITY option, since it is MySQL-specific
+ */
+ $savepoint = $olde = null;
+ $numrowsinserted = 0;
+ if ( in_array( 'IGNORE', $insertOptions ) ) {
+ $savepoint = new SavepointPostgres( $this, 'mw', $this->queryLogger );
+ $olde = error_reporting( 0 );
+ $savepoint->savepoint();
+ }
+
+ $res = parent::nativeInsertSelect( $destTable, $srcTable, $varMap, $conds, $fname,
+ $insertOptions, $selectOptions, $selectJoinConds );
+
+ if ( $savepoint ) {
+ $bar = pg_result_error( $this->mLastResult );
+ if ( $bar != false ) {
+ $savepoint->rollback();
+ } else {
+ $savepoint->release();
+ $numrowsinserted++;
+ }
+ error_reporting( $olde );
+ $savepoint->commit();
+
+ // Set the affected row count for the whole operation
+ $this->mAffectedRows = $numrowsinserted;
+
+ // IGNORE always returns true
+ return true;
+ }
+
+ return $res;
+ }
+
+ public function tableName( $name, $format = 'quoted' ) {
+ // Replace reserved words with better ones
+ $name = $this->remappedTableName( $name );
+
+ return parent::tableName( $name, $format );
+ }
+
+ /**
+ * @param string $name
+ * @return string Value of $name or remapped name if $name is a reserved keyword
+ */
+ public function remappedTableName( $name ) {
+ return isset( $this->keywordTableMap[$name] ) ? $this->keywordTableMap[$name] : $name;
+ }
+
+ /**
+ * @param string $name
+ * @param string $format
+ * @return string Qualified and encoded (if requested) table name
+ */
+ public function realTableName( $name, $format = 'quoted' ) {
+ return parent::tableName( $name, $format );
+ }
+
+ public function nextSequenceValue( $seqName ) {
+ return new NextSequenceValue;
+ }
+
+ /**
+ * Return the current value of a sequence. Assumes it has been nextval'ed in this session.
+ *
+ * @param string $seqName
+ * @return int
+ */
+ public function currentSequenceValue( $seqName ) {
+ $safeseq = str_replace( "'", "''", $seqName );
+ $res = $this->query( "SELECT currval('$safeseq')" );
+ $row = $this->fetchRow( $res );
+ $currval = $row[0];
+
+ return $currval;
+ }
+
+ public function textFieldSize( $table, $field ) {
+ $table = $this->tableName( $table );
+ $sql = "SELECT t.typname as ftype,a.atttypmod as size
+ FROM pg_class c, pg_attribute a, pg_type t
+ WHERE relname='$table' AND a.attrelid=c.oid AND
+ a.atttypid=t.oid and a.attname='$field'";
+ $res = $this->query( $sql );
+ $row = $this->fetchObject( $res );
+ if ( $row->ftype == 'varchar' ) {
+ $size = $row->size - 4;
+ } else {
+ $size = $row->size;
+ }
+
+ return $size;
+ }
+
+ public function limitResult( $sql, $limit, $offset = false ) {
+ return "$sql LIMIT $limit " . ( is_numeric( $offset ) ? " OFFSET {$offset} " : '' );
+ }
+
+ public function wasDeadlock() {
+ return $this->lastErrno() == '40P01';
+ }
+
+ public function duplicateTableStructure(
+ $oldName, $newName, $temporary = false, $fname = __METHOD__
+ ) {
+ $newName = $this->addIdentifierQuotes( $newName );
+ $oldName = $this->addIdentifierQuotes( $oldName );
+
+ return $this->query( 'CREATE ' . ( $temporary ? 'TEMPORARY ' : '' ) . " TABLE $newName " .
+ "(LIKE $oldName INCLUDING DEFAULTS INCLUDING INDEXES)", $fname );
+ }
+
+ public function listTables( $prefix = null, $fname = __METHOD__ ) {
+ $eschema = $this->addQuotes( $this->getCoreSchema() );
+ $result = $this->query(
+ "SELECT tablename FROM pg_tables WHERE schemaname = $eschema", $fname );
+ $endArray = [];
+
+ foreach ( $result as $table ) {
+ $vars = get_object_vars( $table );
+ $table = array_pop( $vars );
+ if ( !$prefix || strpos( $table, $prefix ) === 0 ) {
+ $endArray[] = $table;
+ }
+ }
+
+ return $endArray;
+ }
+
+ public function timestamp( $ts = 0 ) {
+ $ct = new ConvertibleTimestamp( $ts );
+
+ return $ct->getTimestamp( TS_POSTGRES );
+ }
+
+ /**
+ * Posted by cc[plus]php[at]c2se[dot]com on 25-Mar-2009 09:12
+ * to https://secure.php.net/manual/en/ref.pgsql.php
+ *
+ * Parsing a postgres array can be a tricky problem, he's my
+ * take on this, it handles multi-dimensional arrays plus
+ * escaping using a nasty regexp to determine the limits of each
+ * data-item.
+ *
+ * This should really be handled by PHP PostgreSQL module
+ *
+ * @since 1.19
+ * @param string $text Postgreql array returned in a text form like {a,b}
+ * @param string[] $output
+ * @param int|bool $limit
+ * @param int $offset
+ * @return string[]
+ */
+ private function pg_array_parse( $text, &$output, $limit = false, $offset = 1 ) {
+ if ( false === $limit ) {
+ $limit = strlen( $text ) - 1;
+ $output = [];
+ }
+ if ( '{}' == $text ) {
+ return $output;
+ }
+ do {
+ if ( '{' != $text[$offset] ) {
+ preg_match( "/(\\{?\"([^\"\\\\]|\\\\.)*\"|[^,{}]+)+([,}]+)/",
+ $text, $match, 0, $offset );
+ $offset += strlen( $match[0] );
+ $output[] = ( '"' != $match[1][0]
+ ? $match[1]
+ : stripcslashes( substr( $match[1], 1, -1 ) ) );
+ if ( '},' == $match[3] ) {
+ return $output;
+ }
+ } else {
+ $offset = $this->pg_array_parse( $text, $output, $limit, $offset + 1 );
+ }
+ } while ( $limit > $offset );
+
+ return $output;
+ }
+
+ public function aggregateValue( $valuedata, $valuename = 'value' ) {
+ return $valuedata;
+ }
+
+ public function getSoftwareLink() {
+ return '[{{int:version-db-postgres-url}} PostgreSQL]';
+ }
+
+ /**
+ * Return current schema (executes SELECT current_schema())
+ * Needs transaction
+ *
+ * @since 1.19
+ * @return string Default schema for the current session
+ */
+ public function getCurrentSchema() {
+ $res = $this->query( "SELECT current_schema()", __METHOD__ );
+ $row = $this->fetchRow( $res );
+
+ return $row[0];
+ }
+
+ /**
+ * Return list of schemas which are accessible without schema name
+ * This is list does not contain magic keywords like "$user"
+ * Needs transaction
+ *
+ * @see getSearchPath()
+ * @see setSearchPath()
+ * @since 1.19
+ * @return array List of actual schemas for the current sesson
+ */
+ public function getSchemas() {
+ $res = $this->query( "SELECT current_schemas(false)", __METHOD__ );
+ $row = $this->fetchRow( $res );
+ $schemas = [];
+
+ /* PHP pgsql support does not support array type, "{a,b}" string is returned */
+
+ return $this->pg_array_parse( $row[0], $schemas );
+ }
+
+ /**
+ * Return search patch for schemas
+ * This is different from getSchemas() since it contain magic keywords
+ * (like "$user").
+ * Needs transaction
+ *
+ * @since 1.19
+ * @return array How to search for table names schemas for the current user
+ */
+ public function getSearchPath() {
+ $res = $this->query( "SHOW search_path", __METHOD__ );
+ $row = $this->fetchRow( $res );
+
+ /* PostgreSQL returns SHOW values as strings */
+
+ return explode( ",", $row[0] );
+ }
+
+ /**
+ * Update search_path, values should already be sanitized
+ * Values may contain magic keywords like "$user"
+ * @since 1.19
+ *
+ * @param array $search_path List of schemas to be searched by default
+ */
+ private function setSearchPath( $search_path ) {
+ $this->query( "SET search_path = " . implode( ", ", $search_path ) );
+ }
+
+ /**
+ * Determine default schema for the current application
+ * Adjust this session schema search path if desired schema exists
+ * and is not alread there.
+ *
+ * We need to have name of the core schema stored to be able
+ * to query database metadata.
+ *
+ * This will be also called by the installer after the schema is created
+ *
+ * @since 1.19
+ *
+ * @param string $desiredSchema
+ */
+ public function determineCoreSchema( $desiredSchema ) {
+ $this->begin( __METHOD__, self::TRANSACTION_INTERNAL );
+ if ( $this->schemaExists( $desiredSchema ) ) {
+ if ( in_array( $desiredSchema, $this->getSchemas() ) ) {
+ $this->mCoreSchema = $desiredSchema;
+ $this->queryLogger->debug(
+ "Schema \"" . $desiredSchema . "\" already in the search path\n" );
+ } else {
+ /**
+ * Prepend our schema (e.g. 'mediawiki') in front
+ * of the search path
+ * Fixes T17816
+ */
+ $search_path = $this->getSearchPath();
+ array_unshift( $search_path,
+ $this->addIdentifierQuotes( $desiredSchema ) );
+ $this->setSearchPath( $search_path );
+ $this->mCoreSchema = $desiredSchema;
+ $this->queryLogger->debug(
+ "Schema \"" . $desiredSchema . "\" added to the search path\n" );
+ }
+ } else {
+ $this->mCoreSchema = $this->getCurrentSchema();
+ $this->queryLogger->debug(
+ "Schema \"" . $desiredSchema . "\" not found, using current \"" .
+ $this->mCoreSchema . "\"\n" );
+ }
+ /* Commit SET otherwise it will be rollbacked on error or IGNORE SELECT */
+ $this->commit( __METHOD__, self::FLUSHING_INTERNAL );
+ }
+
+ /**
+ * Return schema name for core application tables
+ *
+ * @since 1.19
+ * @return string Core schema name
+ */
+ public function getCoreSchema() {
+ return $this->mCoreSchema;
+ }
+
+ public function getServerVersion() {
+ if ( !isset( $this->numericVersion ) ) {
+ $conn = $this->getBindingHandle();
+ $versionInfo = pg_version( $conn );
+ if ( version_compare( $versionInfo['client'], '7.4.0', 'lt' ) ) {
+ // Old client, abort install
+ $this->numericVersion = '7.3 or earlier';
+ } elseif ( isset( $versionInfo['server'] ) ) {
+ // Normal client
+ $this->numericVersion = $versionInfo['server'];
+ } else {
+ // T18937: broken pgsql extension from PHP<5.3
+ $this->numericVersion = pg_parameter_status( $conn, 'server_version' );
+ }
+ }
+
+ return $this->numericVersion;
+ }
+
+ /**
+ * Query whether a given relation exists (in the given schema, or the
+ * default mw one if not given)
+ * @param string $table
+ * @param array|string $types
+ * @param bool|string $schema
+ * @return bool
+ */
+ private function relationExists( $table, $types, $schema = false ) {
+ if ( !is_array( $types ) ) {
+ $types = [ $types ];
+ }
+ if ( $schema === false ) {
+ $schema = $this->getCoreSchema();
+ }
+ $table = $this->realTableName( $table, 'raw' );
+ $etable = $this->addQuotes( $table );
+ $eschema = $this->addQuotes( $schema );
+ $sql = "SELECT 1 FROM pg_catalog.pg_class c, pg_catalog.pg_namespace n "
+ . "WHERE c.relnamespace = n.oid AND c.relname = $etable AND n.nspname = $eschema "
+ . "AND c.relkind IN ('" . implode( "','", $types ) . "')";
+ $res = $this->query( $sql );
+ $count = $res ? $res->numRows() : 0;
+
+ return (bool)$count;
+ }
+
+ /**
+ * For backward compatibility, this function checks both tables and views.
+ * @param string $table
+ * @param string $fname
+ * @param bool|string $schema
+ * @return bool
+ */
+ public function tableExists( $table, $fname = __METHOD__, $schema = false ) {
+ return $this->relationExists( $table, [ 'r', 'v' ], $schema );
+ }
+
+ public function sequenceExists( $sequence, $schema = false ) {
+ return $this->relationExists( $sequence, 'S', $schema );
+ }
+
+ public function triggerExists( $table, $trigger ) {
+ $q = <<<SQL
+ SELECT 1 FROM pg_class, pg_namespace, pg_trigger
+ WHERE relnamespace=pg_namespace.oid AND relkind='r'
+ AND tgrelid=pg_class.oid
+ AND nspname=%s AND relname=%s AND tgname=%s
+SQL;
+ $res = $this->query(
+ sprintf(
+ $q,
+ $this->addQuotes( $this->getCoreSchema() ),
+ $this->addQuotes( $table ),
+ $this->addQuotes( $trigger )
+ )
+ );
+ if ( !$res ) {
+ return null;
+ }
+ $rows = $res->numRows();
+
+ return $rows;
+ }
+
+ public function ruleExists( $table, $rule ) {
+ $exists = $this->selectField( 'pg_rules', 'rulename',
+ [
+ 'rulename' => $rule,
+ 'tablename' => $table,
+ 'schemaname' => $this->getCoreSchema()
+ ]
+ );
+
+ return $exists === $rule;
+ }
+
+ public function constraintExists( $table, $constraint ) {
+ $sql = sprintf( "SELECT 1 FROM information_schema.table_constraints " .
+ "WHERE constraint_schema = %s AND table_name = %s AND constraint_name = %s",
+ $this->addQuotes( $this->getCoreSchema() ),
+ $this->addQuotes( $table ),
+ $this->addQuotes( $constraint )
+ );
+ $res = $this->query( $sql );
+ if ( !$res ) {
+ return null;
+ }
+ $rows = $res->numRows();
+
+ return $rows;
+ }
+
+ /**
+ * Query whether a given schema exists. Returns true if it does, false if it doesn't.
+ * @param string $schema
+ * @return bool
+ */
+ public function schemaExists( $schema ) {
+ if ( !strlen( $schema ) ) {
+ return false; // short-circuit
+ }
+
+ $exists = $this->selectField(
+ '"pg_catalog"."pg_namespace"', 1, [ 'nspname' => $schema ], __METHOD__ );
+
+ return (bool)$exists;
+ }
+
+ /**
+ * Returns true if a given role (i.e. user) exists, false otherwise.
+ * @param string $roleName
+ * @return bool
+ */
+ public function roleExists( $roleName ) {
+ $exists = $this->selectField( '"pg_catalog"."pg_roles"', 1,
+ [ 'rolname' => $roleName ], __METHOD__ );
+
+ return (bool)$exists;
+ }
+
+ /**
+ * @param string $table
+ * @param string $field
+ * @return PostgresField|null
+ */
+ public function fieldInfo( $table, $field ) {
+ return PostgresField::fromText( $this, $table, $field );
+ }
+
+ /**
+ * pg_field_type() wrapper
+ * @param ResultWrapper|resource $res ResultWrapper or PostgreSQL query result resource
+ * @param int $index Field number, starting from 0
+ * @return string
+ */
+ public function fieldType( $res, $index ) {
+ if ( $res instanceof ResultWrapper ) {
+ $res = $res->result;
+ }
+
+ return pg_field_type( $res, $index );
+ }
+
+ public function encodeBlob( $b ) {
+ return new PostgresBlob( pg_escape_bytea( $b ) );
+ }
+
+ public function decodeBlob( $b ) {
+ if ( $b instanceof PostgresBlob ) {
+ $b = $b->fetch();
+ } elseif ( $b instanceof Blob ) {
+ return $b->fetch();
+ }
+
+ return pg_unescape_bytea( $b );
+ }
+
+ public function strencode( $s ) {
+ // Should not be called by us
+ return pg_escape_string( $this->getBindingHandle(), (string)$s );
+ }
+
+ public function addQuotes( $s ) {
+ $conn = $this->getBindingHandle();
+
+ if ( is_null( $s ) ) {
+ return 'NULL';
+ } elseif ( is_bool( $s ) ) {
+ return intval( $s );
+ } elseif ( $s instanceof Blob ) {
+ if ( $s instanceof PostgresBlob ) {
+ $s = $s->fetch();
+ } else {
+ $s = pg_escape_bytea( $conn, $s->fetch() );
+ }
+ return "'$s'";
+ } elseif ( $s instanceof NextSequenceValue ) {
+ return 'DEFAULT';
+ }
+
+ return "'" . pg_escape_string( $conn, (string)$s ) . "'";
+ }
+
+ /**
+ * Postgres specific version of replaceVars.
+ * Calls the parent version in Database.php
+ *
+ * @param string $ins SQL string, read from a stream (usually tables.sql)
+ * @return string SQL string
+ */
+ protected function replaceVars( $ins ) {
+ $ins = parent::replaceVars( $ins );
+
+ if ( $this->numericVersion >= 8.3 ) {
+ // Thanks for not providing backwards-compatibility, 8.3
+ $ins = preg_replace( "/to_tsvector\s*\(\s*'default'\s*,/", 'to_tsvector(', $ins );
+ }
+
+ if ( $this->numericVersion <= 8.1 ) { // Our minimum version
+ $ins = str_replace( 'USING gin', 'USING gist', $ins );
+ }
+
+ return $ins;
+ }
+
+ public function makeSelectOptions( $options ) {
+ $preLimitTail = $postLimitTail = '';
+ $startOpts = $useIndex = $ignoreIndex = '';
+
+ $noKeyOptions = [];
+ foreach ( $options as $key => $option ) {
+ if ( is_numeric( $key ) ) {
+ $noKeyOptions[$option] = true;
+ }
+ }
+
+ $preLimitTail .= $this->makeGroupByWithHaving( $options );
+
+ $preLimitTail .= $this->makeOrderBy( $options );
+
+ if ( isset( $options['FOR UPDATE'] ) ) {
+ $postLimitTail .= ' FOR UPDATE OF ' .
+ implode( ', ', array_map( [ $this, 'tableName' ], $options['FOR UPDATE'] ) );
+ } elseif ( isset( $noKeyOptions['FOR UPDATE'] ) ) {
+ $postLimitTail .= ' FOR UPDATE';
+ }
+
+ if ( isset( $noKeyOptions['DISTINCT'] ) || isset( $noKeyOptions['DISTINCTROW'] ) ) {
+ $startOpts .= 'DISTINCT';
+ }
+
+ return [ $startOpts, $useIndex, $preLimitTail, $postLimitTail, $ignoreIndex ];
+ }
+
+ public function getDBname() {
+ return $this->mDBname;
+ }
+
+ public function getServer() {
+ return $this->mServer;
+ }
+
+ public function buildConcat( $stringList ) {
+ return implode( ' || ', $stringList );
+ }
+
+ public function buildGroupConcatField(
+ $delimiter, $table, $field, $conds = '', $options = [], $join_conds = []
+ ) {
+ $fld = "array_to_string(array_agg($field)," . $this->addQuotes( $delimiter ) . ')';
+
+ return '(' . $this->selectSQLText( $table, $fld, $conds, null, [], $join_conds ) . ')';
+ }
+
+ public function buildStringCast( $field ) {
+ return $field . '::text';
+ }
+
+ public function streamStatementEnd( &$sql, &$newLine ) {
+ # Allow dollar quoting for function declarations
+ if ( substr( $newLine, 0, 4 ) == '$mw$' ) {
+ if ( $this->delimiter ) {
+ $this->delimiter = false;
+ } else {
+ $this->delimiter = ';';
+ }
+ }
+
+ return parent::streamStatementEnd( $sql, $newLine );
+ }
+
+ public function doLockTables( array $read, array $write, $method ) {
+ $tablesWrite = [];
+ foreach ( $write as $table ) {
+ $tablesWrite[] = $this->tableName( $table );
+ }
+ $tablesRead = [];
+ foreach ( $read as $table ) {
+ $tablesRead[] = $this->tableName( $table );
+ }
+
+ // Acquire locks for the duration of the current transaction...
+ if ( $tablesWrite ) {
+ $this->query(
+ 'LOCK TABLE ONLY ' . implode( ',', $tablesWrite ) . ' IN EXCLUSIVE MODE',
+ $method
+ );
+ }
+ if ( $tablesRead ) {
+ $this->query(
+ 'LOCK TABLE ONLY ' . implode( ',', $tablesRead ) . ' IN SHARE MODE',
+ $method
+ );
+ }
+
+ return true;
+ }
+
+ public function lockIsFree( $lockName, $method ) {
+ // http://www.postgresql.org/docs/8.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
+ $key = $this->addQuotes( $this->bigintFromLockName( $lockName ) );
+ $result = $this->query( "SELECT (CASE(pg_try_advisory_lock($key))
+ WHEN 'f' THEN 'f' ELSE pg_advisory_unlock($key) END) AS lockstatus", $method );
+ $row = $this->fetchObject( $result );
+
+ return ( $row->lockstatus === 't' );
+ }
+
+ public function lock( $lockName, $method, $timeout = 5 ) {
+ // http://www.postgresql.org/docs/8.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
+ $key = $this->addQuotes( $this->bigintFromLockName( $lockName ) );
+ $loop = new WaitConditionLoop(
+ function () use ( $lockName, $key, $timeout, $method ) {
+ $res = $this->query( "SELECT pg_try_advisory_lock($key) AS lockstatus", $method );
+ $row = $this->fetchObject( $res );
+ if ( $row->lockstatus === 't' ) {
+ parent::lock( $lockName, $method, $timeout ); // record
+ return true;
+ }
+
+ return WaitConditionLoop::CONDITION_CONTINUE;
+ },
+ $timeout
+ );
+
+ return ( $loop->invoke() === $loop::CONDITION_REACHED );
+ }
+
+ public function unlock( $lockName, $method ) {
+ // http://www.postgresql.org/docs/8.2/static/functions-admin.html#FUNCTIONS-ADVISORY-LOCKS
+ $key = $this->addQuotes( $this->bigintFromLockName( $lockName ) );
+ $result = $this->query( "SELECT pg_advisory_unlock($key) as lockstatus", $method );
+ $row = $this->fetchObject( $result );
+
+ if ( $row->lockstatus === 't' ) {
+ parent::unlock( $lockName, $method ); // record
+ return true;
+ }
+
+ $this->queryLogger->debug( __METHOD__ . " failed to release lock\n" );
+
+ return false;
+ }
+
+ public function serverIsReadOnly() {
+ $res = $this->query( "SHOW default_transaction_read_only", __METHOD__ );
+ $row = $this->fetchObject( $res );
+
+ return $row ? ( strtolower( $row->default_transaction_read_only ) === 'on' ) : false;
+ }
+
+ /**
+ * @param string $lockName
+ * @return string Integer
+ */
+ private function bigintFromLockName( $lockName ) {
+ return \Wikimedia\base_convert( substr( sha1( $lockName ), 0, 15 ), 16, 10 );
+ }
+}
+
+class_alias( DatabasePostgres::class, 'DatabasePostgres' );