cms/drupal/includes/database/pgsql/database.inc
changeset 541 e756a8c72c3d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cms/drupal/includes/database/pgsql/database.inc	Fri Sep 08 12:04:06 2017 +0200
@@ -0,0 +1,231 @@
+<?php
+
+/**
+ * @file
+ * Database interface code for PostgreSQL database servers.
+ */
+
+/**
+ * @addtogroup database
+ * @{
+ */
+
+/**
+ * The name by which to obtain a lock for retrieving the next insert id.
+ */
+define('POSTGRESQL_NEXTID_LOCK', 1000);
+
+class DatabaseConnection_pgsql extends DatabaseConnection {
+
+  public function __construct(array $connection_options = array()) {
+    // This driver defaults to transaction support, except if explicitly passed FALSE.
+    $this->transactionSupport = !isset($connection_options['transactions']) || ($connection_options['transactions'] !== FALSE);
+
+    // Transactional DDL is always available in PostgreSQL,
+    // but we'll only enable it if standard transactions are.
+    $this->transactionalDDLSupport = $this->transactionSupport;
+
+    // Default to TCP connection on port 5432.
+    if (empty($connection_options['port'])) {
+      $connection_options['port'] = 5432;
+    }
+
+    // PostgreSQL in trust mode doesn't require a password to be supplied.
+    if (empty($connection_options['password'])) {
+      $connection_options['password'] = NULL;
+    }
+    // If the password contains a backslash it is treated as an escape character
+    // http://bugs.php.net/bug.php?id=53217
+    // so backslashes in the password need to be doubled up.
+    // The bug was reported against pdo_pgsql 1.0.2, backslashes in passwords
+    // will break on this doubling up when the bug is fixed, so check the version
+    //elseif (phpversion('pdo_pgsql') < 'version_this_was_fixed_in') {
+    else {
+      $connection_options['password'] = str_replace('\\', '\\\\', $connection_options['password']);
+    }
+
+    $this->connectionOptions = $connection_options;
+
+    $dsn = 'pgsql:host=' . $connection_options['host'] . ' dbname=' . $connection_options['database'] . ' port=' . $connection_options['port'];
+
+    // Allow PDO options to be overridden.
+    $connection_options += array(
+      'pdo' => array(),
+    );
+    $connection_options['pdo'] += array(
+      // Prepared statements are most effective for performance when queries
+      // are recycled (used several times). However, if they are not re-used,
+      // prepared statements become inefficient. Since most of Drupal's
+      // prepared queries are not re-used, it should be faster to emulate
+      // the preparation than to actually ready statements for re-use. If in
+      // doubt, reset to FALSE and measure performance.
+      PDO::ATTR_EMULATE_PREPARES => TRUE,
+      // Convert numeric values to strings when fetching.
+      PDO::ATTR_STRINGIFY_FETCHES => TRUE,
+    );
+    parent::__construct($dsn, $connection_options['username'], $connection_options['password'], $connection_options['pdo']);
+
+    // Force PostgreSQL to use the UTF-8 character set by default.
+    $this->exec("SET NAMES 'UTF8'");
+
+    // Execute PostgreSQL init_commands.
+    if (isset($connection_options['init_commands'])) {
+      $this->exec(implode('; ', $connection_options['init_commands']));
+    }
+  }
+
+  public function prepareQuery($query) {
+    // mapConditionOperator converts LIKE operations to ILIKE for consistency
+    // with MySQL. However, Postgres does not support ILIKE on bytea (blobs)
+    // fields.
+    // To make the ILIKE operator work, we type-cast bytea fields into text.
+    // @todo This workaround only affects bytea fields, but the involved field
+    //   types involved in the query are unknown, so there is no way to
+    //   conditionally execute this for affected queries only.
+    return parent::prepareQuery(preg_replace('/ ([^ ]+) +(I*LIKE|NOT +I*LIKE) /i', ' ${1}::text ${2} ', $query));
+  }
+
+  public function query($query, array $args = array(), $options = array()) {
+
+    $options += $this->defaultOptions();
+
+    // The PDO PostgreSQL driver has a bug which
+    // doesn't type cast booleans correctly when
+    // parameters are bound using associative
+    // arrays.
+    // See http://bugs.php.net/bug.php?id=48383
+    foreach ($args as &$value) {
+      if (is_bool($value)) {
+        $value = (int) $value;
+      }
+    }
+
+    try {
+      if ($query instanceof DatabaseStatementInterface) {
+        $stmt = $query;
+        $stmt->execute(NULL, $options);
+      }
+      else {
+        $this->expandArguments($query, $args);
+        $stmt = $this->prepareQuery($query);
+        $stmt->execute($args, $options);
+      }
+
+      switch ($options['return']) {
+        case Database::RETURN_STATEMENT:
+          return $stmt;
+        case Database::RETURN_AFFECTED:
+          return $stmt->rowCount();
+        case Database::RETURN_INSERT_ID:
+          return $this->lastInsertId($options['sequence_name']);
+        case Database::RETURN_NULL:
+          return;
+        default:
+          throw new PDOException('Invalid return directive: ' . $options['return']);
+      }
+    }
+    catch (PDOException $e) {
+      if ($options['throw_exception']) {
+        // Add additional debug information.
+        if ($query instanceof DatabaseStatementInterface) {
+          $e->query_string = $stmt->getQueryString();
+        }
+        else {
+          $e->query_string = $query;
+        }
+        $e->args = $args;
+        throw $e;
+      }
+      return NULL;
+    }
+  }
+
+  public function queryRange($query, $from, $count, array $args = array(), array $options = array()) {
+    return $this->query($query . ' LIMIT ' . (int) $count . ' OFFSET ' . (int) $from, $args, $options);
+  }
+
+  public function queryTemporary($query, array $args = array(), array $options = array()) {
+    $tablename = $this->generateTemporaryTableName();
+    $this->query('CREATE TEMPORARY TABLE {' . $tablename . '} AS ' . $query, $args, $options);
+    return $tablename;
+  }
+
+  public function driver() {
+    return 'pgsql';
+  }
+
+  public function databaseType() {
+    return 'pgsql';
+  }
+
+  public function mapConditionOperator($operator) {
+    static $specials;
+
+    // Function calls not allowed in static declarations, thus this method.
+    if (!isset($specials)) {
+      $specials = array(
+        // In PostgreSQL, 'LIKE' is case-sensitive. For case-insensitive LIKE
+        // statements, we need to use ILIKE instead.
+        'LIKE' => array('operator' => 'ILIKE'),
+        'NOT LIKE' => array('operator' => 'NOT ILIKE'),
+      );
+    }
+
+    return isset($specials[$operator]) ? $specials[$operator] : NULL;
+  }
+
+  /**
+   * Retrieve the next id in a sequence.
+   *
+   * PostgreSQL has built in sequences. We'll use these instead of inserting
+   * and updating a sequences table.
+   */
+  public function nextId($existing = 0) {
+
+    // Retrieve the name of the sequence. This information cannot be cached
+    // because the prefix may change, for example, like it does in simpletests.
+    $sequence_name = $this->makeSequenceName('sequences', 'value');
+
+    // When PostgreSQL gets a value too small then it will lock the table,
+    // retry the INSERT and if it's still too small then alter the sequence.
+    $id = $this->query("SELECT nextval('" . $sequence_name . "')")->fetchField();
+    if ($id > $existing) {
+      return $id;
+    }
+
+    // PostgreSQL advisory locks are simply locks to be used by an
+    // application such as Drupal. This will prevent other Drupal processes
+    // from altering the sequence while we are.
+    $this->query("SELECT pg_advisory_lock(" . POSTGRESQL_NEXTID_LOCK . ")");
+
+    // While waiting to obtain the lock, the sequence may have been altered
+    // so lets try again to obtain an adequate value.
+    $id = $this->query("SELECT nextval('" . $sequence_name . "')")->fetchField();
+    if ($id > $existing) {
+      $this->query("SELECT pg_advisory_unlock(" . POSTGRESQL_NEXTID_LOCK . ")");
+      return $id;
+    }
+
+    // Reset the sequence to a higher value than the existing id.
+    $this->query("ALTER SEQUENCE " . $sequence_name . " RESTART WITH " . ($existing + 1));
+
+    // Retrieve the next id. We know this will be as high as we want it.
+    $id = $this->query("SELECT nextval('" . $sequence_name . "')")->fetchField();
+
+    $this->query("SELECT pg_advisory_unlock(" . POSTGRESQL_NEXTID_LOCK . ")");
+
+    return $id;
+  }
+
+  public function utf8mb4IsActive() {
+    return TRUE;
+  }
+
+  public function utf8mb4IsSupported() {
+    return TRUE;
+  }
+}
+
+/**
+ * @} End of "addtogroup database".
+ */