class DeleteQuery in Drupal 7

General class for an abstracted DELETE operation.

Hierarchy

• class \Query implements QueryPlaceholderInterface
  • class \DeleteQuery implements QueryConditionInterface

Related topics

Database abstraction layer

Allow the use of different database servers using the same code base.

1 string reference to 'DeleteQuery'

DatabaseConnection::delete in includes/database/database.inc

Prepares and returns a DELETE query object.

File

includes/database/query.inc, line 733

Non-specific Database query code. Used by all engines.

class DeleteQuery extends Query implements QueryConditionInterface {

  /**
   * The table from which to delete.
   *
   * @var string
   */
  protected $table;

  /**
   * The condition object for this query.
   *
   * Condition handling is handled via composition.
   *
   * @var DatabaseCondition
   */
  protected $condition;

  /**
   * Constructs a DeleteQuery object.
   *
   * @param DatabaseConnection $connection
   *   A DatabaseConnection object.
   * @param string $table
   *   Name of the table to associate with this query.
   * @param array $options
   *   Array of database options.
   */
  public function __construct(DatabaseConnection $connection, $table, array $options = array()) {
    $options['return'] = Database::RETURN_AFFECTED;
    parent::__construct($connection, $options);
    $this->table = $table;
    $this->condition = new DatabaseCondition('AND');
  }

  /**
   * Implements QueryConditionInterface::condition().
   */
  public function condition($field, $value = NULL, $operator = NULL) {
    $this->condition
      ->condition($field, $value, $operator);
    return $this;
  }

  /**
   * Implements QueryConditionInterface::isNull().
   */
  public function isNull($field) {
    $this->condition
      ->isNull($field);
    return $this;
  }

  /**
   * Implements QueryConditionInterface::isNotNull().
   */
  public function isNotNull($field) {
    $this->condition
      ->isNotNull($field);
    return $this;
  }

  /**
   * Implements QueryConditionInterface::exists().
   */
  public function exists(SelectQueryInterface $select) {
    $this->condition
      ->exists($select);
    return $this;
  }

  /**
   * Implements QueryConditionInterface::notExists().
   */
  public function notExists(SelectQueryInterface $select) {
    $this->condition
      ->notExists($select);
    return $this;
  }

  /**
   * Implements QueryConditionInterface::conditions().
   */
  public function &conditions() {
    return $this->condition
      ->conditions();
  }

  /**
   * Implements QueryConditionInterface::arguments().
   */
  public function arguments() {
    return $this->condition
      ->arguments();
  }

  /**
   * Implements QueryConditionInterface::where().
   */
  public function where($snippet, $args = array()) {
    $this->condition
      ->where($snippet, $args);
    return $this;
  }

  /**
   * Implements QueryConditionInterface::compile().
   */
  public function compile(DatabaseConnection $connection, QueryPlaceholderInterface $queryPlaceholder) {
    return $this->condition
      ->compile($connection, $queryPlaceholder);
  }

  /**
   * Implements QueryConditionInterface::compiled().
   */
  public function compiled() {
    return $this->condition
      ->compiled();
  }

  /**
   * Executes the DELETE query.
   *
   * @return int
   *   The number of rows affected by the delete query.
   */
  public function execute() {
    $values = array();
    if (count($this->condition)) {
      $this->condition
        ->compile($this->connection, $this);
      $values = $this->condition
        ->arguments();
    }
    return $this->connection
      ->query((string) $this, $values, $this->queryOptions);
  }

  /**
   * Implements PHP magic __toString method to convert the query to a string.
   *
   * @return string
   *   The prepared statement.
   */
  public function __toString() {

    // Create a sanitized comment string to prepend to the query.
    $comments = $this->connection
      ->makeComment($this->comments);
    $query = $comments . 'DELETE FROM {' . $this->connection
      ->escapeTable($this->table) . '} ';
    if (count($this->condition)) {
      $this->condition
        ->compile($this->connection, $this);
      $query .= "\nWHERE " . $this->condition;
    }
    return $query;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
DeleteQuery::$condition	protected	property	The condition object for this query.
DeleteQuery::$table	protected	property	The table from which to delete.
DeleteQuery::arguments	public	function	Implements QueryConditionInterface::arguments(). Overrides QueryConditionInterface::arguments
DeleteQuery::compile	public	function	Implements QueryConditionInterface::compile(). Overrides QueryConditionInterface::compile
DeleteQuery::compiled	public	function	Implements QueryConditionInterface::compiled(). Overrides QueryConditionInterface::compiled
DeleteQuery::condition	public	function	Implements QueryConditionInterface::condition(). Overrides QueryConditionInterface::condition
DeleteQuery::conditions	public	function	Implements QueryConditionInterface::conditions(). Overrides QueryConditionInterface::conditions
DeleteQuery::execute	public	function	Executes the DELETE query. Overrides Query::execute	1
DeleteQuery::exists	public	function	Implements QueryConditionInterface::exists(). Overrides QueryConditionInterface::exists
DeleteQuery::isNotNull	public	function	Implements QueryConditionInterface::isNotNull(). Overrides QueryConditionInterface::isNotNull
DeleteQuery::isNull	public	function	Implements QueryConditionInterface::isNull(). Overrides QueryConditionInterface::isNull
DeleteQuery::notExists	public	function	Implements QueryConditionInterface::notExists(). Overrides QueryConditionInterface::notExists
DeleteQuery::where	public	function	Implements QueryConditionInterface::where(). Overrides QueryConditionInterface::where
DeleteQuery::__construct	public	function	Constructs a DeleteQuery object. Overrides Query::__construct
DeleteQuery::__toString	public	function	Implements PHP magic __toString method to convert the query to a string. Overrides Query::__toString
Query::$comments	protected	property	An array of comments that can be prepended to a query.
Query::$connection	protected	property	The connection object on which to run this query.
Query::$connectionKey	protected	property	The key of the connection object.
Query::$connectionTarget	protected	property	The target of the connection object.
Query::$nextPlaceholder	protected	property	The placeholder counter.
Query::$queryOptions	protected	property	The query options to pass on to the connection object.
Query::$uniqueIdentifier	protected	property	A unique identifier for this query object.
Query::comment	public	function	Adds a comment to the query.
Query::getComments	public	function	Returns a reference to the comments array for the query.
Query::nextPlaceholder	public	function	Gets the next placeholder value for this query object. Overrides QueryPlaceholderInterface::nextPlaceholder
Query::uniqueIdentifier	public	function	Returns a unique identifier for this object. Overrides QueryPlaceholderInterface::uniqueIdentifier
Query::__clone	public	function	Implements the magic __clone function.	1
Query::__sleep	public	function	Implements the magic __sleep function to disconnect from the database.
Query::__wakeup	public	function	Implements the magic __wakeup function to reconnect to the database.