class UpdateQuery in Drupal 7

General class for an abstracted UPDATE operation.

Hierarchy

class \Query implements QueryPlaceholderInterface
- class \UpdateQuery implements QueryConditionInterface

File

includes/database/query.inc, line 963: Non-specific Database query code. Used by all engines.

View source

class UpdateQuery extends Query implements QueryConditionInterface {

  /**
   * The table to update.
   *
   * @var string
   */
  protected $table;

  /**
   * An array of fields that will be updated.
   *
   * @var array
   */
  protected $fields = array();

  /**
   * An array of values to update to.
   *
   * @var array
   */
  protected $arguments = array();

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

  /**
   * Array of fields to update to an expression in case of a duplicate record.
   *
   * This variable is a nested array in the following format:
   * @code
   * <some field> => array(
   *  'condition' => <condition to execute, as a string>,
   *  'arguments' => <array of arguments for condition, or NULL for none>,
   * );
   * @endcode
   *
   * @var array
   */
  protected $expressionFields = array();

  /**
   * Constructs an UpdateQuery 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();
  }

  /**
   * Adds a set of field->value pairs to be updated.
   *
   * @param $fields
   *   An associative array of fields to write into the database. The array keys
   *   are the field names and the values are the values to which to set them.
   *
   * @return UpdateQuery
   *   The called object.
   */
  public function fields(array $fields) {
    $this->fields = $fields;
    return $this;
  }

  /**
   * Specifies fields to be updated as an expression.
   *
   * Expression fields are cases such as counter=counter+1. This method takes
   * precedence over fields().
   *
   * @param $field
   *   The field to set.
   * @param $expression
   *   The field will be set to the value of this expression. This parameter
   *   may include named placeholders.
   * @param $arguments
   *   If specified, this is an array of key/value pairs for named placeholders
   *   corresponding to the expression.
   *
   * @return UpdateQuery
   *   The called object.
   */
  public function expression($field, $expression, array $arguments = NULL) {
    $this->expressionFields[$field] = array(
      'expression' => $expression,
      'arguments' => $arguments,
    );
    return $this;
  }

  /**
   * Executes the UPDATE query.
   *
   * @return
   *   The number of rows affected by the update.
   */
  public function execute() {

    // Expressions take priority over literal fields, so we process those first
    // and remove any literal fields that conflict.
    $fields = $this->fields;
    $update_values = array();
    foreach ($this->expressionFields as $field => $data) {
      if (!empty($data['arguments'])) {
        $update_values += $data['arguments'];
      }
      unset($fields[$field]);
    }

    // Because we filter $fields the same way here and in __toString(), the
    // placeholders will all match up properly.
    $max_placeholder = 0;
    foreach ($fields as $field => $value) {
      $update_values[':db_update_placeholder_' . $max_placeholder++] = $value;
    }
    if (count($this->condition)) {
      $this->condition
        ->compile($this->connection, $this);
      $update_values = array_merge($update_values, $this->condition
        ->arguments());
    }
    return $this->connection
      ->query((string) $this, $update_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);

    // Expressions take priority over literal fields, so we process those first
    // and remove any literal fields that conflict.
    $fields = $this->fields;
    $update_fields = array();
    foreach ($this->expressionFields as $field => $data) {
      $update_fields[] = $field . '=' . $data['expression'];
      unset($fields[$field]);
    }
    $max_placeholder = 0;
    foreach ($fields as $field => $value) {
      $update_fields[] = $field . '=:db_update_placeholder_' . $max_placeholder++;
    }
    $query = $comments . 'UPDATE {' . $this->connection
      ->escapeTable($this->table) . '} SET ' . implode(', ', $update_fields);
    if (count($this->condition)) {
      $this->condition
        ->compile($this->connection, $this);

      // There is an implicit string cast on $this->condition.
      $query .= "\nWHERE " . $this->condition;
    }
    return $query;
  }

}

Members

Name	Modifiers	Type	Description	Overrides
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::$uniqueIdentifier	protected	property	A unique identifier for this query object.
Query::comment	public	function	Adds a comment to the query.
Query::getComments	public	function	Returns a reference to the comments array for the query.
Query::nextPlaceholder	public	function	Gets the next placeholder value for this query object. Overrides QueryPlaceholderInterface::nextPlaceholder
Query::uniqueIdentifier	public	function	Returns a unique identifier for this object. Overrides QueryPlaceholderInterface::uniqueIdentifier
Query::__clone	public	function	Implements the magic __clone function.	1
Query::__sleep	public	function	Implements the magic __sleep function to disconnect from the database.
Query::__wakeup	public	function	Implements the magic __wakeup function to reconnect to the database.
UpdateQuery::$arguments	protected	property	An array of values to update to.
UpdateQuery::$condition	protected	property	The condition object for this query.
UpdateQuery::$expressionFields	protected	property	Array of fields to update to an expression in case of a duplicate record.
UpdateQuery::$fields	protected	property	An array of fields that will be updated.
UpdateQuery::$table	protected	property	The table to update.
UpdateQuery::arguments	public	function	Implements QueryConditionInterface::arguments(). Overrides QueryConditionInterface::arguments
UpdateQuery::compile	public	function	Implements QueryConditionInterface::compile(). Overrides QueryConditionInterface::compile
UpdateQuery::compiled	public	function	Implements QueryConditionInterface::compiled(). Overrides QueryConditionInterface::compiled
UpdateQuery::condition	public	function	Implements QueryConditionInterface::condition(). Overrides QueryConditionInterface::condition
UpdateQuery::conditions	public	function	Implements QueryConditionInterface::conditions(). Overrides QueryConditionInterface::conditions
UpdateQuery::execute	public	function	Executes the UPDATE query. Overrides Query::execute	2
UpdateQuery::exists	public	function	Implements QueryConditionInterface::exists(). Overrides QueryConditionInterface::exists
UpdateQuery::expression	public	function	Specifies fields to be updated as an expression.
UpdateQuery::fields	public	function	Adds a set of field->value pairs to be updated.
UpdateQuery::isNotNull	public	function	Implements QueryConditionInterface::isNotNull(). Overrides QueryConditionInterface::isNotNull
UpdateQuery::isNull	public	function	Implements QueryConditionInterface::isNull(). Overrides QueryConditionInterface::isNull
UpdateQuery::notExists	public	function	Implements QueryConditionInterface::notExists(). Overrides QueryConditionInterface::notExists
UpdateQuery::where	public	function	Implements QueryConditionInterface::where(). Overrides QueryConditionInterface::where
UpdateQuery::__construct	public	function	Constructs an UpdateQuery object. Overrides Query::__construct
UpdateQuery::__toString	public	function	Implements PHP magic __toString method to convert the query to a string. Overrides Query::__toString	1

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class UpdateQuery in Drupal 7

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