Wpdb::query() WP 0.71

Click here to view original web page at wp-kama.ru

Выполняет любые запросы к базе данных WordPress.

Этот метод подразумевает выполнение всех запросов кроме SELECT. Для SELECT есть специальные методы: $wpdb->get_results, $wpdb->get_row, $wpdb->get_col, $wpdb->get_var.

Имейте ввиду, что как и для всех функций класса wpdb, передаваемые параметры нужно очистить от SQL инъекций, сделать это можно двумя способами:

// способ 1
esc_sql( $user_entered_data_string )

// способ 2
$wpdb->prepare(  'query' , value_parameter[, value_parameter ... ] )

Подробнее читайте в секции "Защита запросов от SQL инъекций"

Возвращает

Число/true/false.

true — для запросов CREATE, ALTER, TRUNCATE, DROP.
Число — для задействованных строк остальных запросов (удалены/изменены/выбраны).
false — когда запрос вызвал ошибку.

Использование

global $wpdb;
$wpdb->query( $query );

Примеры

#1. Удалить произвольное поле 'gargle' и его значение у поста 13

$wpdb->query( "DELETE FROM $wpdb->postmeta WHERE post_id = '13' AND meta_key = 'gargle'" );

#2. Установить родительскую страницу 7 для страницы 15

$wpdb->query( "UPDATE $wpdb->posts SET post_parent = 7 WHERE ID = 15 AND post_status = 'static'" );

#3. Удалить осиротевшие произвольные поля

$wpdb->query("DELETE pm FROM $wpdb->postmeta pm LEFT JOIN wp_posts wp ON wp.ID = pm.post_id WHERE wp.ID IS NULL");

#4. Изменим ключ у полей-повторителей ACF

$wpdb->query( "
	UPDATE $wpdb->postmeta
	SET meta_key = REPLACE(meta_key, 'knowledge-base-type', 'knowledge-base-list')
	WHERE `meta_key` LIKE '%knowledge-base-type%'
" );

Список изменений

public function query( $query ) {
	if ( ! $this->ready ) {
		$this->check_current_query = true;
		return false;
	}

	/**
	 * Filters the database query.
	 *
	 * Some queries are made before the plugins have been loaded,
	 * and thus cannot be filtered with this method.
	 *
	 * @since 2.1.0
	 *
	 * @param string $query Database query.
	 */
	$query = apply_filters( 'query', $query );

	if ( ! $query ) {
		$this->insert_id = 0;
		return false;
	}

	$this->flush();

	// Log how the function was called.
	$this->func_call = "\$db->query(\"$query\")";

	// If we're writing to the database, make sure the query will write safely.
	if ( $this->check_current_query && ! $this->check_ascii( $query ) ) {
		$stripped_query = $this->strip_invalid_text_from_query( $query );
		// strip_invalid_text_from_query() can perform queries, so we need
		// to flush again, just to make sure everything is clear.
		$this->flush();
		if ( $stripped_query !== $query ) {
			$this->insert_id = 0;
			return false;
		}
	}

	$this->check_current_query = true;

	// Keep track of the last query for debug.
	$this->last_query = $query;

	$this->_do_query( $query );

	// MySQL server has gone away, try to reconnect.
	$mysql_errno = 0;
	if ( ! empty( $this->dbh ) ) {
		if ( $this->use_mysqli ) {
			if ( $this->dbh instanceof mysqli ) {
				$mysql_errno = mysqli_errno( $this->dbh );
			} else {
				// $dbh is defined, but isn't a real connection.
				// Something has gone horribly wrong, let's try a reconnect.
				$mysql_errno = 2006;
			}
		} else {
			if ( is_resource( $this->dbh ) ) {
				$mysql_errno = mysql_errno( $this->dbh );
			} else {
				$mysql_errno = 2006;
			}
		}
	}

	if ( empty( $this->dbh ) || 2006 === $mysql_errno ) {
		if ( $this->check_connection() ) {
			$this->_do_query( $query );
		} else {
			$this->insert_id = 0;
			return false;
		}
	}

	// If there is an error then take note of it.
	if ( $this->use_mysqli ) {
		if ( $this->dbh instanceof mysqli ) {
			$this->last_error = mysqli_error( $this->dbh );
		} else {
			$this->last_error = __( 'Unable to retrieve the error message from MySQL' );
		}
	} else {
		if ( is_resource( $this->dbh ) ) {
			$this->last_error = mysql_error( $this->dbh );
		} else {
			$this->last_error = __( 'Unable to retrieve the error message from MySQL' );
		}
	}

	if ( $this->last_error ) {
		// Clear insert_id on a subsequent failed insert.
		if ( $this->insert_id && preg_match( '/^\s*(insert|replace)\s/i', $query ) ) {
			$this->insert_id = 0;
		}

		$this->print_error();
		return false;
	}

	if ( preg_match( '/^\s*(create|alter|truncate|drop)\s/i', $query ) ) {
		$return_val = $this->result;
	} elseif ( preg_match( '/^\s*(insert|delete|update|replace)\s/i', $query ) ) {
		if ( $this->use_mysqli ) {
			$this->rows_affected = mysqli_affected_rows( $this->dbh );
		} else {
			$this->rows_affected = mysql_affected_rows( $this->dbh );
		}
		// Take note of the insert_id.
		if ( preg_match( '/^\s*(insert|replace)\s/i', $query ) ) {
			if ( $this->use_mysqli ) {
				$this->insert_id = mysqli_insert_id( $this->dbh );
			} else {
				$this->insert_id = mysql_insert_id( $this->dbh );
			}
		}
		// Return number of rows affected.
		$return_val = $this->rows_affected;
	} else {
		$num_rows = 0;
		if ( $this->use_mysqli && $this->result instanceof mysqli_result ) {
			while ( $row = mysqli_fetch_object( $this->result ) ) {
				$this->last_result[ $num_rows ] = $row;
				$num_rows++;
			}
		} elseif ( is_resource( $this->result ) ) {
			while ( $row = mysql_fetch_object( $this->result ) ) {
				$this->last_result[ $num_rows ] = $row;
				$num_rows++;
			}
		}

		// Log and return the number of rows selected.
		$this->num_rows = $num_rows;
		$return_val     = $num_rows;
	}

	return $return_val;
}

Статьи