wpdb
WordPress Database Access Abstraction Object
Description Description
It is possible to replace this class with your own by setting the $wpdb global variable in wp-content/db.php file to your class. The wpdb class will still be included, so you can extend it or simply use your own.
Source Source
File: wp-includes/wp-db.php
class wpdb {
/**
* Whether to show SQL/DB errors.
*
* Default behavior is to show errors if both WP_DEBUG and WP_DEBUG_DISPLAY
* evaluated to true.
*
* @since 0.71
* @var bool
*/
var $show_errors = false;
/**
* Whether to suppress errors during the DB bootstrapping.
*
* @since 2.5.0
* @var bool
*/
var $suppress_errors = false;
/**
* The last error during query.
*
* @since 2.5.0
* @var string
*/
public $last_error = '';
/**
* Amount of queries made
*
* @since 1.2.0
* @var int
*/
public $num_queries = 0;
/**
* Count of rows returned by previous query
*
* @since 0.71
* @var int
*/
public $num_rows = 0;
/**
* Count of affected rows by previous query
*
* @since 0.71
* @var int
*/
var $rows_affected = 0;
/**
* The ID generated for an AUTO_INCREMENT column by the previous query (usually INSERT).
*
* @since 0.71
* @var int
*/
public $insert_id = 0;
/**
* Last query made
*
* @since 0.71
* @var array
*/
var $last_query;
/**
* Results of the last query made
*
* @since 0.71
* @var array|null
*/
var $last_result;
/**
* MySQL result, which is either a resource or boolean.
*
* @since 0.71
* @var mixed
*/
protected $result;
/**
* Cached column info, for sanity checking data before inserting
*
* @since 4.2.0
* @var array
*/
protected $col_meta = array();
/**
* Calculated character sets on tables
*
* @since 4.2.0
* @var array
*/
protected $table_charset = array();
/**
* Whether text fields in the current query need to be sanity checked.
*
* @since 4.2.0
* @var bool
*/
protected $check_current_query = true;
/**
* Flag to ensure we don't run into recursion problems when checking the collation.
*
* @since 4.2.0
* @see wpdb::check_safe_collation()
* @var bool
*/
private $checking_collation = false;
/**
* Saved info on the table column
*
* @since 0.71
* @var array
*/
protected $col_info;
/**
* Log of queries that were executed, for debugging purposes.
*
* @since 1.5.0
* @since 2.5.0 The third element in each query log was added to record the calling functions.
* @since 5.1.0 The fourth element in each query log was added to record the start time.
*
* @var array[] {
* Array of queries that were executed.
*
* @type array ...$0 {
* Data for each query.
*
* @type string $0 The query's SQL.
* @type float $1 Total time spent on the query, in seconds.
* @type string $2 Comma separated list of the calling functions.
* @type float $3 Unix timestamp of the time at the start of the query.
* }
* }
*/
var $queries;
/**
* The number of times to retry reconnecting before dying.
*
* @since 3.9.0
* @see wpdb::check_connection()
* @var int
*/
protected $reconnect_retries = 5;
/**
* WordPress table prefix
*
* You can set this to have multiple WordPress installations
* in a single database. The second reason is for possible
* security precautions.
*
* @since 2.5.0
* @var string
*/
public $prefix = '';
/**
* WordPress base table prefix.
*
* @since 3.0.0
* @var string
*/
public $base_prefix;
/**
* Whether the database queries are ready to start executing.
*
* @since 2.3.2
* @var bool
*/
var $ready = false;
/**
* Blog ID.
*
* @since 3.0.0
* @var int
*/
public $blogid = 0;
/**
* Site ID.
*
* @since 3.0.0
* @var int
*/
public $siteid = 0;
/**
* List of WordPress per-blog tables
*
* @since 2.5.0
* @see wpdb::tables()
* @var array
*/
var $tables = array(
'posts',
'comments',
'links',
'options',
'postmeta',
'terms',
'term_taxonomy',
'term_relationships',
'termmeta',
'commentmeta',
);
/**
* List of deprecated WordPress tables
*
* categories, post2cat, and link2cat were deprecated in 2.3.0, db version 5539
*
* @since 2.9.0
* @see wpdb::tables()
* @var array
*/
var $old_tables = array( 'categories', 'post2cat', 'link2cat' );
/**
* List of WordPress global tables
*
* @since 3.0.0
* @see wpdb::tables()
* @var array
*/
var $global_tables = array( 'users', 'usermeta' );
/**
* List of Multisite global tables
*
* @since 3.0.0
* @see wpdb::tables()
* @var array
*/
var $ms_global_tables = array(
'blogs',
'blogmeta',
'signups',
'site',
'sitemeta',
'sitecategories',
'registration_log',
'blog_versions',
);
/**
* WordPress Comments table
*
* @since 1.5.0
* @var string
*/
public $comments;
/**
* WordPress Comment Metadata table
*
* @since 2.9.0
* @var string
*/
public $commentmeta;
/**
* WordPress Links table
*
* @since 1.5.0
* @var string
*/
public $links;
/**
* WordPress Options table
*
* @since 1.5.0
* @var string
*/
public $options;
/**
* WordPress Post Metadata table
*
* @since 1.5.0
* @var string
*/
public $postmeta;
/**
* WordPress Posts table
*
* @since 1.5.0
* @var string
*/
public $posts;
/**
* WordPress Terms table
*
* @since 2.3.0
* @var string
*/
public $terms;
/**
* WordPress Term Relationships table
*
* @since 2.3.0
* @var string
*/
public $term_relationships;
/**
* WordPress Term Taxonomy table
*
* @since 2.3.0
* @var string
*/
public $term_taxonomy;
/**
* WordPress Term Meta table.
*
* @since 4.4.0
* @var string
*/
public $termmeta;
//
// Global and Multisite tables
//
/**
* WordPress User Metadata table
*
* @since 2.3.0
* @var string
*/
public $usermeta;
/**
* WordPress Users table
*
* @since 1.5.0
* @var string
*/
public $users;
/**
* Multisite Blogs table
*
* @since 3.0.0
* @var string
*/
public $blogs;
/**
* Multisite Blog Metadata table
*
* @since 5.1.0
* @var string
*/
public $blogmeta;
/**
* Multisite Blog Versions table
*
* @since 3.0.0
* @var string
*/
public $blog_versions;
/**
* Multisite Registration Log table
*
* @since 3.0.0
* @var string
*/
public $registration_log;
/**
* Multisite Signups table
*
* @since 3.0.0
* @var string
*/
public $signups;
/**
* Multisite Sites table
*
* @since 3.0.0
* @var string
*/
public $site;
/**
* Multisite Sitewide Terms table
*
* @since 3.0.0
* @var string
*/
public $sitecategories;
/**
* Multisite Site Metadata table
*
* @since 3.0.0
* @var string
*/
public $sitemeta;
/**
* Format specifiers for DB columns. Columns not listed here default to %s. Initialized during WP load.
*
* Keys are column names, values are format types: 'ID' => '%d'
*
* @since 2.8.0
* @see wpdb::prepare()
* @see wpdb::insert()
* @see wpdb::update()
* @see wpdb::delete()
* @see wp_set_wpdb_vars()
* @var array
*/
public $field_types = array();
/**
* Database table columns charset
*
* @since 2.2.0
* @var string
*/
public $charset;
/**
* Database table columns collate
*
* @since 2.2.0
* @var string
*/
public $collate;
/**
* Database Username
*
* @since 2.9.0
* @var string
*/
protected $dbuser;
/**
* Database Password
*
* @since 3.1.0
* @var string
*/
protected $dbpassword;
/**
* Database Name
*
* @since 3.1.0
* @var string
*/
protected $dbname;
/**
* Database Host
*
* @since 3.1.0
* @var string
*/
protected $dbhost;
/**
* Database Handle
*
* @since 0.71
* @var string
*/
protected $dbh;
/**
* A textual description of the last query/get_row/get_var call
*
* @since 3.0.0
* @var string
*/
public $func_call;
/**
* Whether MySQL is used as the database engine.
*
* Set in WPDB::db_connect() to true, by default. This is used when checking
* against the required MySQL version for WordPress. Normally, a replacement
* database drop-in (db.php) will skip these checks, but setting this to true
* will force the checks to occur.
*
* @since 3.3.0
* @var bool
*/
public $is_mysql = null;
/**
* A list of incompatible SQL modes.
*
* @since 3.9.0
* @var array
*/
protected $incompatible_modes = array(
'NO_ZERO_DATE',
'ONLY_FULL_GROUP_BY',
'STRICT_TRANS_TABLES',
'STRICT_ALL_TABLES',
'TRADITIONAL',
);
/**
* Whether to use mysqli over mysql.
*
* @since 3.9.0
* @var bool
*/
private $use_mysqli = false;
/**
* Whether we've managed to successfully connect at some point
*
* @since 3.9.0
* @var bool
*/
private $has_connected = false;
/**
* Connects to the database server and selects a database
*
* PHP5 style constructor for compatibility with PHP5. Does
* the actual setting up of the class properties and connection
* to the database.
*
* @link https://core.trac.wordpress.org/ticket/3354
* @since 2.0.8
*
* @global string $wp_version
*
* @param string $dbuser MySQL database user
* @param string $dbpassword MySQL database password
* @param string $dbname MySQL database name
* @param string $dbhost MySQL database host
*/
public function __construct( $dbuser, $dbpassword, $dbname, $dbhost ) {
register_shutdown_function( array( $this, '__destruct' ) );
if ( WP_DEBUG && WP_DEBUG_DISPLAY ) {
$this->show_errors();
}
// Use ext/mysqli if it exists unless WP_USE_EXT_MYSQL is defined as true
if ( function_exists( 'mysqli_connect' ) ) {
$this->use_mysqli = true;
if ( defined( 'WP_USE_EXT_MYSQL' ) ) {
$this->use_mysqli = ! WP_USE_EXT_MYSQL;
}
}
$this->dbuser = $dbuser;
$this->dbpassword = $dbpassword;
$this->dbname = $dbname;
$this->dbhost = $dbhost;
// wp-config.php creation will manually connect when ready.
if ( defined( 'WP_SETUP_CONFIG' ) ) {
return;
}
$this->db_connect();
}
/**
* PHP5 style destructor and will run when database object is destroyed.
*
* @see wpdb::__construct()
* @since 2.0.8
* @return true
*/
public function __destruct() {
return true;
}
/**
* Makes private properties readable for backward compatibility.
*
* @since 3.5.0
*
* @param string $name The private member to get, and optionally process
* @return mixed The private member
*/
public function __get( $name ) {
if ( 'col_info' === $name ) {
$this->load_col_info();
}
return $this->$name;
}
/**
* Makes private properties settable for backward compatibility.
*
* @since 3.5.0
*
* @param string $name The private member to set
* @param mixed $value The value to set
*/
public function __set( $name, $value ) {
$protected_members = array(
'col_meta',
'table_charset',
'check_current_query',
);
if ( in_array( $name, $protected_members, true ) ) {
return;
}
$this->$name = $value;
}
/**
* Makes private properties check-able for backward compatibility.
*
* @since 3.5.0
*
* @param string $name The private member to check
*
* @return bool If the member is set or not
*/
public function __isset( $name ) {
return isset( $this->$name );
}
/**
* Makes private properties un-settable for backward compatibility.
*
* @since 3.5.0
*
* @param string $name The private member to unset
*/
public function __unset( $name ) {
unset( $this->$name );
}
/**
* Set $this->charset and $this->collate
*
* @since 3.1.0
*/
public function init_charset() {
$charset = '';
$collate = '';
if ( function_exists( 'is_multisite' ) && is_multisite() ) {
$charset = 'utf8';
if ( defined( 'DB_COLLATE' ) && DB_COLLATE ) {
$collate = DB_COLLATE;
} else {
$collate = 'utf8_general_ci';
}
} elseif ( defined( 'DB_COLLATE' ) ) {
$collate = DB_COLLATE;
}
if ( defined( 'DB_CHARSET' ) ) {
$charset = DB_CHARSET;
}
$charset_collate = $this->determine_charset( $charset, $collate );
$this->charset = $charset_collate['charset'];
$this->collate = $charset_collate['collate'];
}
/**
* Determines the best charset and collation to use given a charset and collation.
*
* For example, when able, utf8mb4 should be used instead of utf8.
*
* @since 4.6.0
*
* @param string $charset The character set to check.
* @param string $collate The collation to check.
* @return array The most appropriate character set and collation to use.
*/
public function determine_charset( $charset, $collate ) {
if ( ( $this->use_mysqli && ! ( $this->dbh instanceof mysqli ) ) || empty( $this->dbh ) ) {
return compact( 'charset', 'collate' );
}
if ( 'utf8' === $charset && $this->has_cap( 'utf8mb4' ) ) {
$charset = 'utf8mb4';
}
if ( 'utf8mb4' === $charset && ! $this->has_cap( 'utf8mb4' ) ) {
$charset = 'utf8';
$collate = str_replace( 'utf8mb4_', 'utf8_', $collate );
}
if ( 'utf8mb4' === $charset ) {
// _general_ is outdated, so we can upgrade it to _unicode_, instead.
if ( ! $collate || 'utf8_general_ci' === $collate ) {
$collate = 'utf8mb4_unicode_ci';
} else {
$collate = str_replace( 'utf8_', 'utf8mb4_', $collate );
}
}
// _unicode_520_ is a better collation, we should use that when it's available.
if ( $this->has_cap( 'utf8mb4_520' ) && 'utf8mb4_unicode_ci' === $collate ) {
$collate = 'utf8mb4_unicode_520_ci';
}
return compact( 'charset', 'collate' );
}
/**
* Sets the connection's character set.
*
* @since 3.1.0
*
* @param resource $dbh The resource given by mysql_connect
* @param string $charset Optional. The character set. Default null.
* @param string $collate Optional. The collation. Default null.
*/
public function set_charset( $dbh, $charset = null, $collate = null ) {
if ( ! isset( $charset ) ) {
$charset = $this->charset;
}
if ( ! isset( $collate ) ) {
$collate = $this->collate;
}
if ( $this->has_cap( 'collation' ) && ! empty( $charset ) ) {
$set_charset_succeeded = true;
if ( $this->use_mysqli ) {
if ( function_exists( 'mysqli_set_charset' ) && $this->has_cap( 'set_charset' ) ) {
$set_charset_succeeded = mysqli_set_charset( $dbh, $charset );
}
if ( $set_charset_succeeded ) {
$query = $this->prepare( 'SET NAMES %s', $charset );
if ( ! empty( $collate ) ) {
$query .= $this->prepare( ' COLLATE %s', $collate );
}
mysqli_query( $dbh, $query );
}
} else {
if ( function_exists( 'mysql_set_charset' ) && $this->has_cap( 'set_charset' ) ) {
$set_charset_succeeded = mysql_set_charset( $charset, $dbh );
}
if ( $set_charset_succeeded ) {
$query = $this->prepare( 'SET NAMES %s', $charset );
if ( ! empty( $collate ) ) {
$query .= $this->prepare( ' COLLATE %s', $collate );
}
mysql_query( $query, $dbh );
}
}
}
}
/**
* Change the current SQL mode, and ensure its WordPress compatibility.
*
* If no modes are passed, it will ensure the current MySQL server
* modes are compatible.
*
* @since 3.9.0
*
* @param array $modes Optional. A list of SQL modes to set.
*/
public function set_sql_mode( $modes = array() ) {
if ( empty( $modes ) ) {
if ( $this->use_mysqli ) {
$res = mysqli_query( $this->dbh, 'SELECT @@SESSION.sql_mode' );
} else {
$res = mysql_query( 'SELECT @@SESSION.sql_mode', $this->dbh );
}
if ( empty( $res ) ) {
return;
}
if ( $this->use_mysqli ) {
$modes_array = mysqli_fetch_array( $res );
if ( empty( $modes_array[0] ) ) {
return;
}
$modes_str = $modes_array[0];
} else {
$modes_str = mysql_result( $res, 0 );
}
if ( empty( $modes_str ) ) {
return;
}
$modes = explode( ',', $modes_str );
}
$modes = array_change_key_case( $modes, CASE_UPPER );
/**
* Filters the list of incompatible SQL modes to exclude.
*
* @since 3.9.0
*
* @param array $incompatible_modes An array of incompatible modes.
*/
$incompatible_modes = (array) apply_filters( 'incompatible_sql_modes', $this->incompatible_modes );
foreach ( $modes as $i => $mode ) {
if ( in_array( $mode, $incompatible_modes ) ) {
unset( $modes[ $i ] );
}
}
$modes_str = implode( ',', $modes );
if ( $this->use_mysqli ) {
mysqli_query( $this->dbh, "SET SESSION sql_mode='$modes_str'" );
} else {
mysql_query( "SET SESSION sql_mode='$modes_str'", $this->dbh );
}
}
/**
* Sets the table prefix for the WordPress tables.
*
* @since 2.5.0
*
* @param string $prefix Alphanumeric name for the new prefix.
* @param bool $set_table_names Optional. Whether the table names, e.g. wpdb::$posts, should be updated or not.
* @return string|WP_Error Old prefix or WP_Error on error
*/
public function set_prefix( $prefix, $set_table_names = true ) {
if ( preg_match( '|[^a-z0-9_]|i', $prefix ) ) {
return new WP_Error( 'invalid_db_prefix', 'Invalid database prefix' );
}
$old_prefix = is_multisite() ? '' : $prefix;
if ( isset( $this->base_prefix ) ) {
$old_prefix = $this->base_prefix;
}
$this->base_prefix = $prefix;
if ( $set_table_names ) {
foreach ( $this->tables( 'global' ) as $table => $prefixed_table ) {
$this->$table = $prefixed_table;
}
if ( is_multisite() && empty( $this->blogid ) ) {
return $old_prefix;
}
$this->prefix = $this->get_blog_prefix();
foreach ( $this->tables( 'blog' ) as $table => $prefixed_table ) {
$this->$table = $prefixed_table;
}
foreach ( $this->tables( 'old' ) as $table => $prefixed_table ) {
$this->$table = $prefixed_table;
}
}
return $old_prefix;
}
/**
* Sets blog id.
*
* @since 3.0.0
*
* @param int $blog_id
* @param int $network_id Optional.
* @return int previous blog id
*/
public function set_blog_id( $blog_id, $network_id = 0 ) {
if ( ! empty( $network_id ) ) {
$this->siteid = $network_id;
}
$old_blog_id = $this->blogid;
$this->blogid = $blog_id;
$this->prefix = $this->get_blog_prefix();
foreach ( $this->tables( 'blog' ) as $table => $prefixed_table ) {
$this->$table = $prefixed_table;
}
foreach ( $this->tables( 'old' ) as $table => $prefixed_table ) {
$this->$table = $prefixed_table;
}
return $old_blog_id;
}
/**
* Gets blog prefix.
*
* @since 3.0.0
* @param int $blog_id Optional.
* @return string Blog prefix.
*/
public function get_blog_prefix( $blog_id = null ) {
if ( is_multisite() ) {
if ( null === $blog_id ) {
$blog_id = $this->blogid;
}
$blog_id = (int) $blog_id;
if ( defined( 'MULTISITE' ) && ( 0 == $blog_id || 1 == $blog_id ) ) {
return $this->base_prefix;
} else {
return $this->base_prefix . $blog_id . '_';
}
} else {
return $this->base_prefix;
}
}
/**
* Returns an array of WordPress tables.
*
* Also allows for the CUSTOM_USER_TABLE and CUSTOM_USER_META_TABLE to
* override the WordPress users and usermeta tables that would otherwise
* be determined by the prefix.
*
* The scope argument can take one of the following:
*
* 'all' - returns 'all' and 'global' tables. No old tables are returned.
* 'blog' - returns the blog-level tables for the queried blog.
* 'global' - returns the global tables for the installation, returning multisite tables only if running multisite.
* 'ms_global' - returns the multisite global tables, regardless if current installation is multisite.
* 'old' - returns tables which are deprecated.
*
* @since 3.0.0
* @uses wpdb::$tables
* @uses wpdb::$old_tables
* @uses wpdb::$global_tables
* @uses wpdb::$ms_global_tables
*
* @param string $scope Optional. Can be all, global, ms_global, blog, or old tables. Defaults to all.
* @param bool $prefix Optional. Whether to include table prefixes. Default true. If blog
* prefix is requested, then the custom users and usermeta tables will be mapped.
* @param int $blog_id Optional. The blog_id to prefix. Defaults to wpdb::$blogid. Used only when prefix is requested.
* @return array Table names. When a prefix is requested, the key is the unprefixed table name.
*/
public function tables( $scope = 'all', $prefix = true, $blog_id = 0 ) {
switch ( $scope ) {
case 'all':
$tables = array_merge( $this->global_tables, $this->tables );
if ( is_multisite() ) {
$tables = array_merge( $tables, $this->ms_global_tables );
}
break;
case 'blog':
$tables = $this->tables;
break;
case 'global':
$tables = $this->global_tables;
if ( is_multisite() ) {
$tables = array_merge( $tables, $this->ms_global_tables );
}
break;
case 'ms_global':
$tables = $this->ms_global_tables;
break;
case 'old':
$tables = $this->old_tables;
break;
default:
return array();
}
if ( $prefix ) {
if ( ! $blog_id ) {
$blog_id = $this->blogid;
}
$blog_prefix = $this->get_blog_prefix( $blog_id );
$base_prefix = $this->base_prefix;
$global_tables = array_merge( $this->global_tables, $this->ms_global_tables );
foreach ( $tables as $k => $table ) {
if ( in_array( $table, $global_tables ) ) {
$tables[ $table ] = $base_prefix . $table;
} else {
$tables[ $table ] = $blog_prefix . $table;
}
unset( $tables[ $k ] );
}
if ( isset( $tables['users'] ) && defined( 'CUSTOM_USER_TABLE' ) ) {
$tables['users'] = CUSTOM_USER_TABLE;
}
if ( isset( $tables['usermeta'] ) && defined( 'CUSTOM_USER_META_TABLE' ) ) {
$tables['usermeta'] = CUSTOM_USER_META_TABLE;
}
}
return $tables;
}
/**
* Selects a database using the current database connection.
*
* The database name will be changed based on the current database
* connection. On failure, the execution will bail and display an DB error.
*
* @since 0.71
*
* @param string $db MySQL database name
* @param resource|null $dbh Optional link identifier.
*/
public function select( $db, $dbh = null ) {
if ( is_null( $dbh ) ) {
$dbh = $this->dbh;
}
if ( $this->use_mysqli ) {
$success = mysqli_select_db( $dbh, $db );
} else {
$success = mysql_select_db( $db, $dbh );
}
if ( ! $success ) {
$this->ready = false;
if ( ! did_action( 'template_redirect' ) ) {
wp_load_translations_early();
$message = '<h1>' . __( 'Can’t select database' ) . "</h1>\n";
$message .= '<p>' . sprintf(
/* translators: %s: database name */
__( 'We were able to connect to the database server (which means your username and password is okay) but not able to select the %s database.' ),
'<code>' . htmlspecialchars( $db, ENT_QUOTES ) . '</code>'
) . "</p>\n";
$message .= "<ul>\n";
$message .= '<li>' . __( 'Are you sure it exists?' ) . "</li>\n";
$message .= '<li>' . sprintf(
/* translators: 1: database user, 2: database name */
__( 'Does the user %1$s have permission to use the %2$s database?' ),
'<code>' . htmlspecialchars( $this->dbuser, ENT_QUOTES ) . '</code>',
'<code>' . htmlspecialchars( $db, ENT_QUOTES ) . '</code>'
) . "</li>\n";
$message .= '<li>' . sprintf(
/* translators: %s: database name */
__( 'On some systems the name of your database is prefixed with your username, so it would be like <code>username_%1$s</code>. Could that be the problem?' ),
htmlspecialchars( $db, ENT_QUOTES )
) . "</li>\n";
$message .= "</ul>\n";
$message .= '<p>' . sprintf(
/* translators: %s: support forums URL */
__( 'If you don’t know how to set up a database you should <strong>contact your host</strong>. If all else fails you may find help at the <a href="%s">WordPress Support Forums</a>.' ),
__( 'https://wordpress.org/support/' )
) . "</p>\n";
$this->bail( $message, 'db_select_fail' );
}
}
}
/**
* Do not use, deprecated.
*
* Use esc_sql() or wpdb::prepare() instead.
*
* @since 2.8.0
* @deprecated 3.6.0 Use wpdb::prepare()
* @see wpdb::prepare
* @see esc_sql()
*
* @param string $string
* @return string
*/
function _weak_escape( $string ) {
if ( func_num_args() === 1 && function_exists( '_deprecated_function' ) ) {
_deprecated_function( __METHOD__, '3.6.0', 'wpdb::prepare() or esc_sql()' );
}
return addslashes( $string );
}
/**
* Real escape, using mysqli_real_escape_string() or mysql_real_escape_string()
*
* @see mysqli_real_escape_string()
* @see mysql_real_escape_string()
* @since 2.8.0
*
* @param string $string to escape
* @return string escaped
*/
function _real_escape( $string ) {
if ( $this->dbh ) {
if ( $this->use_mysqli ) {
$escaped = mysqli_real_escape_string( $this->dbh, $string );
} else {
$escaped = mysql_real_escape_string( $string, $this->dbh );
}
} else {
$class = get_class( $this );
if ( function_exists( '__' ) ) {
/* translators: %s: database access abstraction class, usually wpdb or a class extending wpdb */
_doing_it_wrong( $class, sprintf( __( '%s must set a database connection for use with escaping.' ), $class ), '3.6.0' );
} else {
_doing_it_wrong( $class, sprintf( '%s must set a database connection for use with escaping.', $class ), '3.6.0' );
}
$escaped = addslashes( $string );
}
return $this->add_placeholder_escape( $escaped );
}
/**
* Escape data. Works on arrays.
*
* @uses wpdb::_real_escape()
* @since 2.8.0
*
* @param string|array $data
* @return string|array escaped
*/
public function _escape( $data ) {
if ( is_array( $data ) ) {
foreach ( $data as $k => $v ) {
if ( is_array( $v ) ) {
$data[ $k ] = $this->_escape( $v );
} else {
$data[ $k ] = $this->_real_escape( $v );
}
}
} else {
$data = $this->_real_escape( $data );
}
return $data;
}
/**
* Do not use, deprecated.
*
* Use esc_sql() or wpdb::prepare() instead.
*
* @since 0.71
* @deprecated 3.6.0 Use wpdb::prepare()
* @see wpdb::prepare()
* @see esc_sql()
*
* @param mixed $data
* @return mixed
*/
public function escape( $data ) {
if ( func_num_args() === 1 && function_exists( '_deprecated_function' ) ) {
_deprecated_function( __METHOD__, '3.6.0', 'wpdb::prepare() or esc_sql()' );
}
if ( is_array( $data ) ) {
foreach ( $data as $k => $v ) {
if ( is_array( $v ) ) {
$data[ $k ] = $this->escape( $v, 'recursive' );
} else {
$data[ $k ] = $this->_weak_escape( $v, 'internal' );
}
}
} else {
$data = $this->_weak_escape( $data, 'internal' );
}
return $data;
}
/**
* Escapes content by reference for insertion into the database, for security
*
* @uses wpdb::_real_escape()
*
* @since 2.3.0
*
* @param string $string to escape
*/
public function escape_by_ref( &$string ) {
if ( ! is_float( $string ) ) {
$string = $this->_real_escape( $string );
}
}
/**
* Prepares a SQL query for safe execution. Uses sprintf()-like syntax.
*
* The following placeholders can be used in the query string:
* %d (integer)
* %f (float)
* %s (string)
*
* All placeholders MUST be left unquoted in the query string. A corresponding argument MUST be passed for each placeholder.
*
* For compatibility with old behavior, numbered or formatted string placeholders (eg, %1$s, %5s) will not have quotes
* added by this function, so should be passed with appropriate quotes around them for your usage.
*
* Literal percentage signs (%) in the query string must be written as %%. Percentage wildcards (for example,
* to use in LIKE syntax) must be passed via a substitution argument containing the complete LIKE string, these
* cannot be inserted directly in the query string. Also see {@see wpdb::esc_like()}.
*
* Arguments may be passed as individual arguments to the method, or as a single array containing all arguments. A combination
* of the two is not supported.
*
* Examples:
* $wpdb->prepare( "SELECT * FROM `table` WHERE `column` = %s AND `field` = %d OR `other_field` LIKE %s", array( 'foo', 1337, '%bar' ) );
* $wpdb->prepare( "SELECT DATE_FORMAT(`field`, '%%c') FROM `table` WHERE `column` = %s", 'foo' );
*
* @link https://secure.php.net/sprintf Description of syntax.
* @since 2.3.0
*
* @param string $query Query statement with sprintf()-like placeholders
* @param array|mixed $args The array of variables to substitute into the query's placeholders if being called with an array of arguments,
* or the first variable to substitute into the query's placeholders if being called with individual arguments.
* @param mixed $args,... further variables to substitute into the query's placeholders if being called wih individual arguments.
* @return string|void Sanitized query string, if there is a query to prepare.
*/
public function prepare( $query, $args ) {
if ( is_null( $query ) ) {
return;
}
// This is not meant to be foolproof -- but it will catch obviously incorrect usage.
if ( strpos( $query, '%' ) === false ) {
wp_load_translations_early();
_doing_it_wrong( 'wpdb::prepare', sprintf( __( 'The query argument of %s must have a placeholder.' ), 'wpdb::prepare()' ), '3.9.0' );
}
$args = func_get_args();
array_shift( $args );
// If args were passed as an array (as in vsprintf), move them up.
$passed_as_array = false;
if ( is_array( $args[0] ) && count( $args ) == 1 ) {
$passed_as_array = true;
$args = $args[0];
}
foreach ( $args as $arg ) {
if ( ! is_scalar( $arg ) && ! is_null( $arg ) ) {
wp_load_translations_early();
_doing_it_wrong( 'wpdb::prepare', sprintf( __( 'Unsupported value type (%s).' ), gettype( $arg ) ), '4.8.2' );
}
}
/*
* Specify the formatting allowed in a placeholder. The following are allowed:
*
* - Sign specifier. eg, $+d
* - Numbered placeholders. eg, %1$s
* - Padding specifier, including custom padding characters. eg, %05s, %'#5s
* - Alignment specifier. eg, %05-s
* - Precision specifier. eg, %.2f
*/
$allowed_format = '(?:[1-9][0-9]*[$])?[-+0-9]*(?: |0|\'.)?[-+0-9]*(?:\.[0-9]+)?';
/*
* If a %s placeholder already has quotes around it, removing the existing quotes and re-inserting them
* ensures the quotes are consistent.
*
* For backwards compatibility, this is only applied to %s, and not to placeholders like %1$s, which are frequently
* used in the middle of longer strings, or as table name placeholders.
*/
$query = str_replace( "'%s'", '%s', $query ); // Strip any existing single quotes.
$query = str_replace( '"%s"', '%s', $query ); // Strip any existing double quotes.
$query = preg_replace( '/(?<!%)%s/', "'%s'", $query ); // Quote the strings, avoiding escaped strings like %%s.
$query = preg_replace( "/(?<!%)(%($allowed_format)?f)/", '%\\2F', $query ); // Force floats to be locale unaware.
$query = preg_replace( "/%(?:%|$|(?!($allowed_format)?[sdF]))/", '%%\\1', $query ); // Escape any unescaped percents.
// Count the number of valid placeholders in the query.
$placeholders = preg_match_all( "/(^|[^%]|(%%)+)%($allowed_format)?[sdF]/", $query, $matches );
if ( count( $args ) !== $placeholders ) {
if ( 1 === $placeholders && $passed_as_array ) {
// If the passed query only expected one argument, but the wrong number of arguments were sent as an array, bail.
wp_load_translations_early();
_doing_it_wrong( 'wpdb::prepare', __( 'The query only expected one placeholder, but an array of multiple placeholders was sent.' ), '4.9.0' );
return;
} else {
/*
* If we don't have the right number of placeholders, but they were passed as individual arguments,
* or we were expecting multiple arguments in an array, throw a warning.
*/
wp_load_translations_early();
_doing_it_wrong(
'wpdb::prepare',
/* translators: 1: number of placeholders, 2: number of arguments passed */
sprintf(
__( 'The query does not contain the correct number of placeholders (%1$d) for the number of arguments passed (%2$d).' ),
$placeholders,
count( $args )
),
'4.8.3'
);
}
}
array_walk( $args, array( $this, 'escape_by_ref' ) );
$query = @vsprintf( $query, $args );
return $this->add_placeholder_escape( $query );
}
/**
* First half of escaping for LIKE special characters % and _ before preparing for MySQL.
*
* Use this only before wpdb::prepare() or esc_sql(). Reversing the order is very bad for security.
*
* Example Prepared Statement:
*
* $wild = '%';
* $find = 'only 43% of planets';
* $like = $wild . $wpdb->esc_like( $find ) . $wild;
* $sql = $wpdb->prepare( "SELECT * FROM $wpdb->posts WHERE post_content LIKE %s", $like );
*
* Example Escape Chain:
*
* $sql = esc_sql( $wpdb->esc_like( $input ) );
*
* @since 4.0.0
*
* @param string $text The raw text to be escaped. The input typed by the user should have no
* extra or deleted slashes.
* @return string Text in the form of a LIKE phrase. The output is not SQL safe. Call $wpdb::prepare()
* or real_escape next.
*/
public function esc_like( $text ) {
return addcslashes( $text, '_%\\' );
}
/**
* Print SQL/DB error.
*
* @since 0.71
* @global array $EZSQL_ERROR Stores error information of query and error string
*
* @param string $str The error to display
* @return false|void False if the showing of errors is disabled.
*/
public function print_error( $str = '' ) {
global $EZSQL_ERROR;
if ( ! $str ) {
if ( $this->use_mysqli ) {
$str = mysqli_error( $this->dbh );
} else {
$str = mysql_error( $this->dbh );
}
}
$EZSQL_ERROR[] = array(
'query' => $this->last_query,
'error_str' => $str,
);
if ( $this->suppress_errors ) {
return false;
}
wp_load_translations_early();
if ( $caller = $this->get_caller() ) {
/* translators: 1: Database error message, 2: SQL query, 3: Name of the calling function */
$error_str = sprintf( __( 'WordPress database error %1$s for query %2$s made by %3$s' ), $str, $this->last_query, $caller );
} else {
/* translators: 1: Database error message, 2: SQL query */
$error_str = sprintf( __( 'WordPress database error %1$s for query %2$s' ), $str, $this->last_query );
}
error_log( $error_str );
// Are we showing errors?
if ( ! $this->show_errors ) {
return false;
}
// If there is an error then take note of it
if ( is_multisite() ) {
$msg = sprintf(
"%s [%s]\n%s\n",
__( 'WordPress database error:' ),
$str,
$this->last_query
);
if ( defined( 'ERRORLOGFILE' ) ) {
error_log( $msg, 3, ERRORLOGFILE );
}
if ( defined( 'DIEONDBERROR' ) ) {
wp_die( $msg );
}
} else {
$str = htmlspecialchars( $str, ENT_QUOTES );
$query = htmlspecialchars( $this->last_query, ENT_QUOTES );
printf(
'<div id="error"><p class="wpdberror"><strong>%s</strong> [%s]<br /><code>%s</code></p></div>',
__( 'WordPress database error:' ),
$str,
$query
);
}
}
/**
* Enables showing of database errors.
*
* This function should be used only to enable showing of errors.
* wpdb::hide_errors() should be used instead for hiding of errors. However,
* this function can be used to enable and disable showing of database
* errors.
*
* @since 0.71
* @see wpdb::hide_errors()
*
* @param bool $show Whether to show or hide errors
* @return bool Old value for showing errors.
*/
public function show_errors( $show = true ) {
$errors = $this->show_errors;
$this->show_errors = $show;
return $errors;
}
/**
* Disables showing of database errors.
*
* By default database errors are not shown.
*
* @since 0.71
* @see wpdb::show_errors()
*
* @return bool Whether showing of errors was active
*/
public function hide_errors() {
$show = $this->show_errors;
$this->show_errors = false;
return $show;
}
/**
* Whether to suppress database errors.
*
* By default database errors are suppressed, with a simple
* call to this function they can be enabled.
*
* @since 2.5.0
* @see wpdb::hide_errors()
* @param bool $suppress Optional. New value. Defaults to true.
* @return bool Old value
*/
public function suppress_errors( $suppress = true ) {
$errors = $this->suppress_errors;
$this->suppress_errors = (bool) $suppress;
return $errors;
}
/**
* Kill cached query results.
*
* @since 0.71
*/
public function flush() {
$this->last_result = array();
$this->col_info = null;
$this->last_query = null;
$this->rows_affected = $this->num_rows = 0;
$this->last_error = '';
if ( $this->use_mysqli && $this->result instanceof mysqli_result ) {
mysqli_free_result( $this->result );
$this->result = null;
// Sanity check before using the handle
if ( empty( $this->dbh ) || ! ( $this->dbh instanceof mysqli ) ) {
return;
}
// Clear out any results from a multi-query
while ( mysqli_more_results( $this->dbh ) ) {
mysqli_next_result( $this->dbh );
}
} elseif ( is_resource( $this->result ) ) {
mysql_free_result( $this->result );
}
}
/**
* Connect to and select database.
*
* If $allow_bail is false, the lack of database connection will need
* to be handled manually.
*
* @since 3.0.0
* @since 3.9.0 $allow_bail parameter added.
*
* @param bool $allow_bail Optional. Allows the function to bail. Default true.
* @return bool True with a successful connection, false on failure.
*/
public function db_connect( $allow_bail = true ) {
$this->is_mysql = true;
/*
* Deprecated in 3.9+ when using MySQLi. No equivalent
* $new_link parameter exists for mysqli_* functions.
*/
$new_link = defined( 'MYSQL_NEW_LINK' ) ? MYSQL_NEW_LINK : true;
$client_flags = defined( 'MYSQL_CLIENT_FLAGS' ) ? MYSQL_CLIENT_FLAGS : 0;
if ( $this->use_mysqli ) {
$this->dbh = mysqli_init();
$host = $this->dbhost;
$port = null;
$socket = null;
$is_ipv6 = false;
if ( $host_data = $this->parse_db_host( $this->dbhost ) ) {
list( $host, $port, $socket, $is_ipv6 ) = $host_data;
}
/*
* If using the `mysqlnd` library, the IPv6 address needs to be
* enclosed in square brackets, whereas it doesn't while using the
* `libmysqlclient` library.
* @see https://bugs.php.net/bug.php?id=67563
*/
if ( $is_ipv6 && extension_loaded( 'mysqlnd' ) ) {
$host = "[$host]";
}
if ( WP_DEBUG ) {
mysqli_real_connect( $this->dbh, $host, $this->dbuser, $this->dbpassword, null, $port, $socket, $client_flags );
} else {
@mysqli_real_connect( $this->dbh, $host, $this->dbuser, $this->dbpassword, null, $port, $socket, $client_flags );
}
if ( $this->dbh->connect_errno ) {
$this->dbh = null;
/*
* It's possible ext/mysqli is misconfigured. Fall back to ext/mysql if:
* - We haven't previously connected, and
* - WP_USE_EXT_MYSQL isn't set to false, and
* - ext/mysql is loaded.
*/
$attempt_fallback = true;
if ( $this->has_connected ) {
$attempt_fallback = false;
} elseif ( defined( 'WP_USE_EXT_MYSQL' ) && ! WP_USE_EXT_MYSQL ) {
$attempt_fallback = false;
} elseif ( ! function_exists( 'mysql_connect' ) ) {
$attempt_fallback = false;
}
if ( $attempt_fallback ) {
$this->use_mysqli = false;
return $this->db_connect( $allow_bail );
}
}
} else {
if ( WP_DEBUG ) {
$this->dbh = mysql_connect( $this->dbhost, $this->dbuser, $this->dbpassword, $new_link, $client_flags );
} else {
$this->dbh = @mysql_connect( $this->dbhost, $this->dbuser, $this->dbpassword, $new_link, $client_flags );
}
}
if ( ! $this->dbh && $allow_bail ) {
wp_load_translations_early();
// Load custom DB error template, if present.
if ( file_exists( WP_CONTENT_DIR . '/db-error.php' ) ) {
require_once( WP_CONTENT_DIR . '/db-error.php' );
die();
}
$message = '<h1>' . __( 'Error establishing a database connection' ) . "</h1>\n";
$message .= '<p>' . sprintf(
/* translators: 1: wp-config.php, 2: database host */
__( 'This either means that the username and password information in your %1$s file is incorrect or we can’t contact the database server at %2$s. This could mean your host’s database server is down.' ),
'<code>wp-config.php</code>',
'<code>' . htmlspecialchars( $this->dbhost, ENT_QUOTES ) . '</code>'
) . "</p>\n";
$message .= "<ul>\n";
$message .= '<li>' . __( 'Are you sure you have the correct username and password?' ) . "</li>\n";
$message .= '<li>' . __( 'Are you sure that you have typed the correct hostname?' ) . "</li>\n";
$message .= '<li>' . __( 'Are you sure that the database server is running?' ) . "</li>\n";
$message .= "</ul>\n";
$message .= '<p>' . sprintf(
/* translators: %s: support forums URL */
__( 'If you’re unsure what these terms mean you should probably contact your host. If you still need help you can always visit the <a href="%s">WordPress Support Forums</a>.' ),
__( 'https://wordpress.org/support/' )
) . "</p>\n";
$this->bail( $message, 'db_connect_fail' );
return false;
} elseif ( $this->dbh ) {
if ( ! $this->has_connected ) {
$this->init_charset();
}
$this->has_connected = true;
$this->set_charset( $this->dbh );
$this->ready = true;
$this->set_sql_mode();
$this->select( $this->dbname, $this->dbh );
return true;
}
return false;
}
/**
* Parse the DB_HOST setting to interpret it for mysqli_real_connect.
*
* mysqli_real_connect doesn't support the host param including a port or
* socket like mysql_connect does. This duplicates how mysql_connect detects
* a port and/or socket file.
*
* @since 4.9.0
*
* @param string $host The DB_HOST setting to parse.
* @return array|bool Array containing the host, the port, the socket and whether
* it is an IPv6 address, in that order. If $host couldn't be parsed,
* returns false.
*/
public function parse_db_host( $host ) {
$port = null;
$socket = null;
$is_ipv6 = false;
// First peel off the socket parameter from the right, if it exists.
$socket_pos = strpos( $host, ':/' );
if ( $socket_pos !== false ) {
$socket = substr( $host, $socket_pos + 1 );
$host = substr( $host, 0, $socket_pos );
}
// We need to check for an IPv6 address first.
// An IPv6 address will always contain at least two colons.
if ( substr_count( $host, ':' ) > 1 ) {
$pattern = '#^(?:\[)?(?P<host>[0-9a-fA-F:]+)(?:\]:(?P<port>[\d]+))?#';
$is_ipv6 = true;
} else {
// We seem to be dealing with an IPv4 address.
$pattern = '#^(?P<host>[^:/]*)(?::(?P<port>[\d]+))?#';
}
$matches = array();
$result = preg_match( $pattern, $host, $matches );
if ( 1 !== $result ) {
// Couldn't parse the address, bail.
return false;
}
$host = '';
foreach ( array( 'host', 'port' ) as $component ) {
if ( ! empty( $matches[ $component ] ) ) {
$$component = $matches[ $component ];
}
}
return array( $host, $port, $socket, $is_ipv6 );
}
/**
* Checks that the connection to the database is still up. If not, try to reconnect.
*
* If this function is unable to reconnect, it will forcibly die, or if after the
* the {@see 'template_redirect'} hook has been fired, return false instead.
*
* If $allow_bail is false, the lack of database connection will need
* to be handled manually.
*
* @since 3.9.0
*
* @param bool $allow_bail Optional. Allows the function to bail. Default true.
* @return bool|void True if the connection is up.
*/
public function check_connection( $allow_bail = true ) {
if ( $this->use_mysqli ) {
if ( ! empty( $this->dbh ) && mysqli_ping( $this->dbh ) ) {
return true;
}
} else {
if ( ! empty( $this->dbh ) && mysql_ping( $this->dbh ) ) {
return true;
}
}
$error_reporting = false;
// Disable warnings, as we don't want to see a multitude of "unable to connect" messages
if ( WP_DEBUG ) {
$error_reporting = error_reporting();
error_reporting( $error_reporting & ~E_WARNING );
}
for ( $tries = 1; $tries <= $this->reconnect_retries; $tries++ ) {
// On the last try, re-enable warnings. We want to see a single instance of the
// "unable to connect" message on the bail() screen, if it appears.
if ( $this->reconnect_retries === $tries && WP_DEBUG ) {
error_reporting( $error_reporting );
}
if ( $this->db_connect( false ) ) {
if ( $error_reporting ) {
error_reporting( $error_reporting );
}
return true;
}
sleep( 1 );
}
// If template_redirect has already happened, it's too late for wp_die()/dead_db().
// Let's just return and hope for the best.
if ( did_action( 'template_redirect' ) ) {
return false;
}
if ( ! $allow_bail ) {
return false;
}
wp_load_translations_early();
$message = '<h1>' . __( 'Error reconnecting to the database' ) . "</h1>\n";
$message .= '<p>' . sprintf(
/* translators: %s: database host */
__( 'This means that we lost contact with the database server at %s. This could mean your host’s database server is down.' ),
'<code>' . htmlspecialchars( $this->dbhost, ENT_QUOTES ) . '</code>'
) . "</p>\n";
$message .= "<ul>\n";
$message .= '<li>' . __( 'Are you sure that the database server is running?' ) . "</li>\n";
$message .= '<li>' . __( 'Are you sure that the database server is not under particularly heavy load?' ) . "</li>\n";
$message .= "</ul>\n";
$message .= '<p>' . sprintf(
/* translators: %s: support forums URL */
__( 'If you’re unsure what these terms mean you should probably contact your host. If you still need help you can always visit the <a href="%s">WordPress Support Forums</a>.' ),
__( 'https://wordpress.org/support/' )
) . "</p>\n";
// We weren't able to reconnect, so we better bail.
$this->bail( $message, 'db_connect_fail' );
// Call dead_db() if bail didn't die, because this database is no more. It has ceased to be (at least temporarily).
dead_db();
}
/**
* Perform a MySQL database query, using current database connection.
*
* More information can be found on the codex page.
*
* @since 0.71
*
* @param string $query Database query
* @return int|bool Boolean true for CREATE, ALTER, TRUNCATE and DROP queries. Number of rows
* affected/selected for all other queries. Boolean false on error.
*/
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 );
$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 number of rows the query returned
// and return number of rows selected
$this->num_rows = $num_rows;
$return_val = $num_rows;
}
return $return_val;
}
/**
* Internal function to perform the mysql_query() call.
*
* @since 3.9.0
*
* @see wpdb::query()
*
* @param string $query The query to run.
*/
private function _do_query( $query ) {
if ( defined( 'SAVEQUERIES' ) && SAVEQUERIES ) {
$this->timer_start();
}
if ( ! empty( $this->dbh ) && $this->use_mysqli ) {
$this->result = mysqli_query( $this->dbh, $query );
} elseif ( ! empty( $this->dbh ) ) {
$this->result = mysql_query( $query, $this->dbh );
}
$this->num_queries++;
if ( defined( 'SAVEQUERIES' ) && SAVEQUERIES ) {
$this->queries[] = array(
$query,
$this->timer_stop(),
$this->get_caller(),
$this->time_start,
);
}
}
/**
* Generates and returns a placeholder escape string for use in queries returned by ::prepare().
*
* @since 4.8.3
*
* @return string String to escape placeholders.
*/
public function placeholder_escape() {
static $placeholder;
if ( ! $placeholder ) {
// If ext/hash is not present, compat.php's hash_hmac() does not support sha256.
$algo = function_exists( 'hash' ) ? 'sha256' : 'sha1';
// Old WP installs may not have AUTH_SALT defined.
$salt = defined( 'AUTH_SALT' ) && AUTH_SALT ? AUTH_SALT : (string) rand();
$placeholder = '{' . hash_hmac( $algo, uniqid( $salt, true ), $salt ) . '}';
}
/*
* Add the filter to remove the placeholder escaper. Uses priority 0, so that anything
* else attached to this filter will recieve the query with the placeholder string removed.
*/
if ( ! has_filter( 'query', array( $this, 'remove_placeholder_escape' ) ) ) {
add_filter( 'query', array( $this, 'remove_placeholder_escape' ), 0 );
}
return $placeholder;
}
/**
* Adds a placeholder escape string, to escape anything that resembles a printf() placeholder.
*
* @since 4.8.3
*
* @param string $query The query to escape.
* @return string The query with the placeholder escape string inserted where necessary.
*/
public function add_placeholder_escape( $query ) {
/*
* To prevent returning anything that even vaguely resembles a placeholder,
* we clobber every % we can find.
*/
return str_replace( '%', $this->placeholder_escape(), $query );
}
/**
* Removes the placeholder escape strings from a query.
*
* @since 4.8.3
*
* @param string $query The query from which the placeholder will be removed.
* @return string The query with the placeholder removed.
*/
public function remove_placeholder_escape( $query ) {
return str_replace( $this->placeholder_escape(), '%', $query );
}
/**
* Insert a row into a table.
*
* wpdb::insert( 'table', array( 'column' => 'foo', 'field' => 'bar' ) )
* wpdb::insert( 'table', array( 'column' => 'foo', 'field' => 1337 ), array( '%s', '%d' ) )
*
* @since 2.5.0
* @see wpdb::prepare()
* @see wpdb::$field_types
* @see wp_set_wpdb_vars()
*
* @param string $table Table name
* @param array $data Data to insert (in column => value pairs).
* Both $data columns and $data values should be "raw" (neither should be SQL escaped).
* Sending a null value will cause the column to be set to NULL - the corresponding format is ignored in this case.
* @param array|string $format Optional. An array of formats to be mapped to each of the value in $data.
* If string, that format will be used for all of the values in $data.
* A format is one of '%d', '%f', '%s' (integer, float, string).
* If omitted, all values in $data will be treated as strings unless otherwise specified in wpdb::$field_types.
* @return int|false The number of rows inserted, or false on error.
*/
public function insert( $table, $data, $format = null ) {
return $this->_insert_replace_helper( $table, $data, $format, 'INSERT' );
}
/**
* Replace a row into a table.
*
* wpdb::replace( 'table', array( 'column' => 'foo', 'field' => 'bar' ) )
* wpdb::replace( 'table', array( 'column' => 'foo', 'field' => 1337 ), array( '%s', '%d' ) )
*
* @since 3.0.0
* @see wpdb::prepare()
* @see wpdb::$field_types
* @see wp_set_wpdb_vars()
*
* @param string $table Table name
* @param array $data Data to insert (in column => value pairs).
* Both $data columns and $data values should be "raw" (neither should be SQL escaped).
* Sending a null value will cause the column to be set to NULL - the corresponding format is ignored in this case.
* @param array|string $format Optional. An array of formats to be mapped to each of the value in $data.
* If string, that format will be used for all of the values in $data.
* A format is one of '%d', '%f', '%s' (integer, float, string).
* If omitted, all values in $data will be treated as strings unless otherwise specified in wpdb::$field_types.
* @return int|false The number of rows affected, or false on error.
*/
public function replace( $table, $data, $format = null ) {
return $this->_insert_replace_helper( $table, $data, $format, 'REPLACE' );
}
/**
* Helper function for insert and replace.
*
* Runs an insert or replace query based on $type argument.
*
* @since 3.0.0
* @see wpdb::prepare()
* @see wpdb::$field_types
* @see wp_set_wpdb_vars()
*
* @param string $table Table name
* @param array $data Data to insert (in column => value pairs).
* Both $data columns and $data values should be "raw" (neither should be SQL escaped).
* Sending a null value will cause the column to be set to NULL - the corresponding format is ignored in this case.
* @param array|string $format Optional. An array of formats to be mapped to each of the value in $data.
* If string, that format will be used for all of the values in $data.
* A format is one of '%d', '%f', '%s' (integer, float, string).
* If omitted, all values in $data will be treated as strings unless otherwise specified in wpdb::$field_types.
* @param string $type Optional. What type of operation is this? INSERT or REPLACE. Defaults to INSERT.
* @return int|false The number of rows affected, or false on error.
*/
function _insert_replace_helper( $table, $data, $format = null, $type = 'INSERT' ) {
$this->insert_id = 0;
if ( ! in_array( strtoupper( $type ), array( 'REPLACE', 'INSERT' ) ) ) {
return false;
}
$data = $this->process_fields( $table, $data, $format );
if ( false === $data ) {
return false;
}
$formats = $values = array();
foreach ( $data as $value ) {
if ( is_null( $value['value'] ) ) {
$formats[] = 'NULL';
continue;
}
$formats[] = $value['format'];
$values[] = $value['value'];
}
$fields = '`' . implode( '`, `', array_keys( $data ) ) . '`';
$formats = implode( ', ', $formats );
$sql = "$type INTO `$table` ($fields) VALUES ($formats)";
$this->check_current_query = false;
return $this->query( $this->prepare( $sql, $values ) );
}
/**
* Update a row in the table
*
* wpdb::update( 'table', array( 'column' => 'foo', 'field' => 'bar' ), array( 'ID' => 1 ) )
* wpdb::update( 'table', array( 'column' => 'foo', 'field' => 1337 ), array( 'ID' => 1 ), array( '%s', '%d' ), array( '%d' ) )
*
* @since 2.5.0
* @see wpdb::prepare()
* @see wpdb::$field_types
* @see wp_set_wpdb_vars()
*
* @param string $table Table name
* @param array $data Data to update (in column => value pairs).
* Both $data columns and $data values should be "raw" (neither should be SQL escaped).
* Sending a null value will cause the column to be set to NULL - the corresponding
* format is ignored in this case.
* @param array $where A named array of WHERE clauses (in column => value pairs).
* Multiple clauses will be joined with ANDs.
* Both $where columns and $where values should be "raw".
* Sending a null value will create an IS NULL comparison - the corresponding format will be ignored in this case.
* @param array|string $format Optional. An array of formats to be mapped to each of the values in $data.
* If string, that format will be used for all of the values in $data.
* A format is one of '%d', '%f', '%s' (integer, float, string).
* If omitted, all values in $data will be treated as strings unless otherwise specified in wpdb::$field_types.
* @param array|string $where_format Optional. An array of formats to be mapped to each of the values in $where.
* If string, that format will be used for all of the items in $where.
* A format is one of '%d', '%f', '%s' (integer, float, string).
* If omitted, all values in $where will be treated as strings.
* @return int|false The number of rows updated, or false on error.
*/
public function update( $table, $data, $where, $format = null, $where_format = null ) {
if ( ! is_array( $data ) || ! is_array( $where ) ) {
return false;
}
$data = $this->process_fields( $table, $data, $format );
if ( false === $data ) {
return false;
}
$where = $this->process_fields( $table, $where, $where_format );
if ( false === $where ) {
return false;
}
$fields = $conditions = $values = array();
foreach ( $data as $field => $value ) {
if ( is_null( $value['value'] ) ) {
$fields[] = "`$field` = NULL";
continue;
}
$fields[] = "`$field` = " . $value['format'];
$values[] = $value['value'];
}
foreach ( $where as $field => $value ) {
if ( is_null( $value['value'] ) ) {
$conditions[] = "`$field` IS NULL";
continue;
}
$conditions[] = "`$field` = " . $value['format'];
$values[] = $value['value'];
}
$fields = implode( ', ', $fields );
$conditions = implode( ' AND ', $conditions );
$sql = "UPDATE `$table` SET $fields WHERE $conditions";
$this->check_current_query = false;
return $this->query( $this->prepare( $sql, $values ) );
}
/**
* Delete a row in the table
*
* wpdb::delete( 'table', array( 'ID' => 1 ) )
* wpdb::delete( 'table', array( 'ID' => 1 ), array( '%d' ) )
*
* @since 3.4.0
* @see wpdb::prepare()
* @see wpdb::$field_types
* @see wp_set_wpdb_vars()
*
* @param string $table Table name
* @param array $where A named array of WHERE clauses (in column => value pairs).
* Multiple clauses will be joined with ANDs.
* Both $where columns and $where values should be "raw".
* Sending a null value will create an IS NULL comparison - the corresponding format will be ignored in this case.
* @param array|string $where_format Optional. An array of formats to be mapped to each of the values in $where.
* If string, that format will be used for all of the items in $where.
* A format is one of '%d', '%f', '%s' (integer, float, string).
* If omitted, all values in $where will be treated as strings unless otherwise specified in wpdb::$field_types.
* @return int|false The number of rows updated, or false on error.
*/
public function delete( $table, $where, $where_format = null ) {
if ( ! is_array( $where ) ) {
return false;
}
$where = $this->process_fields( $table, $where, $where_format );
if ( false === $where ) {
return false;
}
$conditions = $values = array();
foreach ( $where as $field => $value ) {
if ( is_null( $value['value'] ) ) {
$conditions[] = "`$field` IS NULL";
continue;
}
$conditions[] = "`$field` = " . $value['format'];
$values[] = $value['value'];
}
$conditions = implode( ' AND ', $conditions );
$sql = "DELETE FROM `$table` WHERE $conditions";
$this->check_current_query = false;
return $this->query( $this->prepare( $sql, $values ) );
}
/**
* Processes arrays of field/value pairs and field formats.
*
* This is a helper method for wpdb's CRUD methods, which take field/value
* pairs for inserts, updates, and where clauses. This method first pairs
* each value with a format. Then it determines the charset of that field,
* using that to determine if any invalid text would be stripped. If text is
* stripped, then field processing is rejected and the query fails.
*
* @since 4.2.0
*
* @param string $table Table name.
* @param array $data Field/value pair.
* @param mixed $format Format for each field.
* @return array|false Returns an array of fields that contain paired values
* and formats. Returns false for invalid values.
*/
protected function process_fields( $table, $data, $format ) {
$data = $this->process_field_formats( $data, $format );
if ( false === $data ) {
return false;
}
$data = $this->process_field_charsets( $data, $table );
if ( false === $data ) {
return false;
}
$data = $this->process_field_lengths( $data, $table );
if ( false === $data ) {
return false;
}
$converted_data = $this->strip_invalid_text( $data );
if ( $data !== $converted_data ) {
return false;
}
return $data;
}
/**
* Prepares arrays of value/format pairs as passed to wpdb CRUD methods.
*
* @since 4.2.0
*
* @param array $data Array of fields to values.
* @param mixed $format Formats to be mapped to the values in $data.
* @return array Array, keyed by field names with values being an array
* of 'value' and 'format' keys.
*/
protected function process_field_formats( $data, $format ) {
$formats = $original_formats = (array) $format;
foreach ( $data as $field => $value ) {
$value = array(
'value' => $value,
'format' => '%s',
);
if ( ! empty( $format ) ) {
$value['format'] = array_shift( $formats );
if ( ! $value['format'] ) {
$value['format'] = reset( $original_formats );
}
} elseif ( isset( $this->field_types[ $field ] ) ) {
$value['format'] = $this->field_types[ $field ];
}
$data[ $field ] = $value;
}
return $data;
}
/**
* Adds field charsets to field/value/format arrays generated by
* the wpdb::process_field_formats() method.
*
* @since 4.2.0
*
* @param array $data As it comes from the wpdb::process_field_formats() method.
* @param string $table Table name.
* @return array|false The same array as $data with additional 'charset' keys.
*/
protected function process_field_charsets( $data, $table ) {
foreach ( $data as $field => $value ) {
if ( '%d' === $value['format'] || '%f' === $value['format'] ) {
/*
* We can skip this field if we know it isn't a string.
* This checks %d/%f versus ! %s because its sprintf() could take more.
*/
$value['charset'] = false;
} else {
$value['charset'] = $this->get_col_charset( $table, $field );
if ( is_wp_error( $value['charset'] ) ) {
return false;
}
}
$data[ $field ] = $value;
}
return $data;
}
/**
* For string fields, record the maximum string length that field can safely save.
*
* @since 4.2.1
*
* @param array $data As it comes from the wpdb::process_field_charsets() method.
* @param string $table Table name.
* @return array|false The same array as $data with additional 'length' keys, or false if
* any of the values were too long for their corresponding field.
*/
protected function process_field_lengths( $data, $table ) {
foreach ( $data as $field => $value ) {
if ( '%d' === $value['format'] || '%f' === $value['format'] ) {
/*
* We can skip this field if we know it isn't a string.
* This checks %d/%f versus ! %s because its sprintf() could take more.
*/
$value['length'] = false;
} else {
$value['length'] = $this->get_col_length( $table, $field );
if ( is_wp_error( $value['length'] ) ) {
return false;
}
}
$data[ $field ] = $value;
}
return $data;
}
/**
* Retrieve one variable from the database.
*
* Executes a SQL query and returns the value from the SQL result.
* If the SQL result contains more than one column and/or more than one row, this function returns the value in the column and row specified.
* If $query is null, this function returns the value in the specified column and row from the previous SQL result.
*
* @since 0.71
*
* @param string|null $query Optional. SQL query. Defaults to null, use the result from the previous query.
* @param int $x Optional. Column of value to return. Indexed from 0.
* @param int $y Optional. Row of value to return. Indexed from 0.
* @return string|null Database query result (as string), or null on failure
*/
public function get_var( $query = null, $x = 0, $y = 0 ) {
$this->func_call = "\$db->get_var(\"$query\", $x, $y)";
if ( $this->check_current_query && $this->check_safe_collation( $query ) ) {
$this->check_current_query = false;
}
if ( $query ) {
$this->query( $query );
}
// Extract var out of cached results based x,y vals
if ( ! empty( $this->last_result[ $y ] ) ) {
$values = array_values( get_object_vars( $this->last_result[ $y ] ) );
}
// If there is a value return it else return null
return ( isset( $values[ $x ] ) && $values[ $x ] !== '' ) ? $values[ $x ] : null;
}
/**
* Retrieve one row from the database.
*
* Executes a SQL query and returns the row from the SQL result.
*
* @since 0.71
*
* @param string|null $query SQL query.
* @param string $output Optional. The required return type. One of OBJECT, ARRAY_A, or ARRAY_N, which correspond to
* an stdClass object, an associative array, or a numeric array, respectively. Default OBJECT.
* @param int $y Optional. Row to return. Indexed from 0.
* @return array|object|null|void Database query result in format specified by $output or null on failure
*/
public function get_row( $query = null, $output = OBJECT, $y = 0 ) {
$this->func_call = "\$db->get_row(\"$query\",$output,$y)";
if ( $this->check_current_query && $this->check_safe_collation( $query ) ) {
$this->check_current_query = false;
}
if ( $query ) {
$this->query( $query );
} else {
return null;
}
if ( ! isset( $this->last_result[ $y ] ) ) {
return null;
}
if ( $output == OBJECT ) {
return $this->last_result[ $y ] ? $this->last_result[ $y ] : null;
} elseif ( $output == ARRAY_A ) {
return $this->last_result[ $y ] ? get_object_vars( $this->last_result[ $y ] ) : null;
} elseif ( $output == ARRAY_N ) {
return $this->last_result[ $y ] ? array_values( get_object_vars( $this->last_result[ $y ] ) ) : null;
} elseif ( strtoupper( $output ) === OBJECT ) {
// Back compat for OBJECT being previously case insensitive.
return $this->last_result[ $y ] ? $this->last_result[ $y ] : null;
} else {
$this->print_error( ' $db->get_row(string query, output type, int offset) -- Output type must be one of: OBJECT, ARRAY_A, ARRAY_N' );
}
}
/**
* Retrieve one column from the database.
*
* Executes a SQL query and returns the column from the SQL result.
* If the SQL result contains more than one column, this function returns the column specified.
* If $query is null, this function returns the specified column from the previous SQL result.
*
* @since 0.71
*
* @param string|null $query Optional. SQL query. Defaults to previous query.
* @param int $x Optional. Column to return. Indexed from 0.
* @return array Database query result. Array indexed from 0 by SQL result row number.
*/
public function get_col( $query = null, $x = 0 ) {
if ( $this->check_current_query && $this->check_safe_collation( $query ) ) {
$this->check_current_query = false;
}
if ( $query ) {
$this->query( $query );
}
$new_array = array();
// Extract the column values
if ( $this->last_result ) {
for ( $i = 0, $j = count( $this->last_result ); $i < $j; $i++ ) {
$new_array[ $i ] = $this->get_var( null, $x, $i );
}
}
return $new_array;
}
/**
* Retrieve an entire SQL result set from the database (i.e., many rows)
*
* Executes a SQL query and returns the entire SQL result.
*
* @since 0.71
*
* @param string $query SQL query.
* @param string $output Optional. Any of ARRAY_A | ARRAY_N | OBJECT | OBJECT_K constants.
* With one of the first three, return an array of rows indexed from 0 by SQL result row number.
* Each row is an associative array (column => value, ...), a numerically indexed array (0 => value, ...), or an object. ( ->column = value ), respectively.
* With OBJECT_K, return an associative array of row objects keyed by the value of each row's first column's value.
* Duplicate keys are discarded.
* @return array|object|null Database query results
*/
public function get_results( $query = null, $output = OBJECT ) {
$this->func_call = "\$db->get_results(\"$query\", $output)";
if ( $this->check_current_query && $this->check_safe_collation( $query ) ) {
$this->check_current_query = false;
}
if ( $query ) {
$this->query( $query );
} else {
return null;
}
$new_array = array();
if ( $output == OBJECT ) {
// Return an integer-keyed array of row objects
return $this->last_result;
} elseif ( $output == OBJECT_K ) {
// Return an array of row objects with keys from column 1
// (Duplicates are discarded)
if ( $this->last_result ) {
foreach ( $this->last_result as $row ) {
$var_by_ref = get_object_vars( $row );
$key = array_shift( $var_by_ref );
if ( ! isset( $new_array[ $key ] ) ) {
$new_array[ $key ] = $row;
}
}
}
return $new_array;
} elseif ( $output == ARRAY_A || $output == ARRAY_N ) {
// Return an integer-keyed array of...
if ( $this->last_result ) {
foreach ( (array) $this->last_result as $row ) {
if ( $output == ARRAY_N ) {
// ...integer-keyed row arrays
$new_array[] = array_values( get_object_vars( $row ) );
} else {
// ...column name-keyed row arrays
$new_array[] = get_object_vars( $row );
}
}
}
return $new_array;
} elseif ( strtoupper( $output ) === OBJECT ) {
// Back compat for OBJECT being previously case insensitive.
return $this->last_result;
}
return null;
}
/**
* Retrieves the character set for the given table.
*
* @since 4.2.0
*
* @param string $table Table name.
* @return string|WP_Error Table character set, WP_Error object if it couldn't be found.
*/
protected function get_table_charset( $table ) {
$tablekey = strtolower( $table );
/**
* Filters the table charset value before the DB is checked.
*
* Passing a non-null value to the filter will effectively short-circuit
* checking the DB for the charset, returning that value instead.
*
* @since 4.2.0
*
* @param string $charset The character set to use. Default null.
* @param string $table The name of the table being checked.
*/
$charset = apply_filters( 'pre_get_table_charset', null, $table );
if ( null !== $charset ) {
return $charset;
}
if ( isset( $this->table_charset[ $tablekey ] ) ) {
return $this->table_charset[ $tablekey ];
}
$charsets = $columns = array();
$table_parts = explode( '.', $table );
$table = '`' . implode( '`.`', $table_parts ) . '`';
$results = $this->get_results( "SHOW FULL COLUMNS FROM $table" );
if ( ! $results ) {
return new WP_Error( 'wpdb_get_table_charset_failure' );
}
foreach ( $results as $column ) {
$columns[ strtolower( $column->Field ) ] = $column;
}
$this->col_meta[ $tablekey ] = $columns;
foreach ( $columns as $column ) {
if ( ! empty( $column->Collation ) ) {
list( $charset ) = explode( '_', $column->Collation );
// If the current connection can't support utf8mb4 characters, let's only send 3-byte utf8 characters.
if ( 'utf8mb4' === $charset && ! $this->has_cap( 'utf8mb4' ) ) {
$charset = 'utf8';
}
$charsets[ strtolower( $charset ) ] = true;
}
list( $type ) = explode( '(', $column->Type );
// A binary/blob means the whole query gets treated like this.
if ( in_array( strtoupper( $type ), array( 'BINARY', 'VARBINARY', 'TINYBLOB', 'MEDIUMBLOB', 'BLOB', 'LONGBLOB' ) ) ) {
$this->table_charset[ $tablekey ] = 'binary';
return 'binary';
}
}
// utf8mb3 is an alias for utf8.
if ( isset( $charsets['utf8mb3'] ) ) {
$charsets['utf8'] = true;
unset( $charsets['utf8mb3'] );
}
// Check if we have more than one charset in play.
$count = count( $charsets );
if ( 1 === $count ) {
$charset = key( $charsets );
} elseif ( 0 === $count ) {
// No charsets, assume this table can store whatever.
$charset = false;
} else {
// More than one charset. Remove latin1 if present and recalculate.
unset( $charsets['latin1'] );
$count = count( $charsets );
if ( 1 === $count ) {
// Only one charset (besides latin1).
$charset = key( $charsets );
} elseif ( 2 === $count && isset( $charsets['utf8'], $charsets['utf8mb4'] ) ) {
// Two charsets, but they're utf8 and utf8mb4, use utf8.
$charset = 'utf8';
} else {
// Two mixed character sets. ascii.
$charset = 'ascii';
}
}
$this->table_charset[ $tablekey ] = $charset;
return $charset;
}
/**
* Retrieves the character set for the given column.
*
* @since 4.2.0
*
* @param string $table Table name.
* @param string $column Column name.
* @return string|false|WP_Error Column character set as a string. False if the column has no
* character set. WP_Error object if there was an error.
*/
public function get_col_charset( $table, $column ) {
$tablekey = strtolower( $table );
$columnkey = strtolower( $column );
/**
* Filters the column charset value before the DB is checked.
*
* Passing a non-null value to the filter will short-circuit
* checking the DB for the charset, returning that value instead.
*
* @since 4.2.0
*
* @param string $charset The character set to use. Default null.
* @param string $table The name of the table being checked.
* @param string $column The name of the column being checked.
*/
$charset = apply_filters( 'pre_get_col_charset', null, $table, $column );
if ( null !== $charset ) {
return $charset;
}
// Skip this entirely if this isn't a MySQL database.
if ( empty( $this->is_mysql ) ) {
return false;
}
if ( empty( $this->table_charset[ $tablekey ] ) ) {
// This primes column information for us.
$table_charset = $this->get_table_charset( $table );
if ( is_wp_error( $table_charset ) ) {
return $table_charset;
}
}
// If still no column information, return the table charset.
if ( empty( $this->col_meta[ $tablekey ] ) ) {
return $this->table_charset[ $tablekey ];
}
// If this column doesn't exist, return the table charset.
if ( empty( $this->col_meta[ $tablekey ][ $columnkey ] ) ) {
return $this->table_charset[ $tablekey ];
}
// Return false when it's not a string column.
if ( empty( $this->col_meta[ $tablekey ][ $columnkey ]->Collation ) ) {
return false;
}
list( $charset ) = explode( '_', $this->col_meta[ $tablekey ][ $columnkey ]->Collation );
return $charset;
}
/**
* Retrieve the maximum string length allowed in a given column.
* The length may either be specified as a byte length or a character length.
*
* @since 4.2.1
*
* @param string $table Table name.
* @param string $column Column name.
* @return array|false|WP_Error array( 'length' => (int), 'type' => 'byte' | 'char' )
* false if the column has no length (for example, numeric column)
* WP_Error object if there was an error.
*/
public function get_col_length( $table, $column ) {
$tablekey = strtolower( $table );
$columnkey = strtolower( $column );
// Skip this entirely if this isn't a MySQL database.
if ( empty( $this->is_mysql ) ) {
return false;
}
if ( empty( $this->col_meta[ $tablekey ] ) ) {
// This primes column information for us.
$table_charset = $this->get_table_charset( $table );
if ( is_wp_error( $table_charset ) ) {
return $table_charset;
}
}
if ( empty( $this->col_meta[ $tablekey ][ $columnkey ] ) ) {
return false;
}
$typeinfo = explode( '(', $this->col_meta[ $tablekey ][ $columnkey ]->Type );
$type = strtolower( $typeinfo[0] );
if ( ! empty( $typeinfo[1] ) ) {
$length = trim( $typeinfo[1], ')' );
} else {
$length = false;
}
switch ( $type ) {
case 'char':
case 'varchar':
return array(
'type' => 'char',
'length' => (int) $length,
);
case 'binary':
case 'varbinary':
return array(
'type' => 'byte',
'length' => (int) $length,
);
case 'tinyblob':
case 'tinytext':
return array(
'type' => 'byte',
'length' => 255, // 2^8 - 1
);
case 'blob':
case 'text':
return array(
'type' => 'byte',
'length' => 65535, // 2^16 - 1
);
case 'mediumblob':
case 'mediumtext':
return array(
'type' => 'byte',
'length' => 16777215, // 2^24 - 1
);
case 'longblob':
case 'longtext':
return array(
'type' => 'byte',
'length' => 4294967295, // 2^32 - 1
);
default:
return false;
}
}
/**
* Check if a string is ASCII.
*
* The negative regex is faster for non-ASCII strings, as it allows
* the search to finish as soon as it encounters a non-ASCII character.
*
* @since 4.2.0
*
* @param string $string String to check.
* @return bool True if ASCII, false if not.
*/
protected function check_ascii( $string ) {
if ( function_exists( 'mb_check_encoding' ) ) {
if ( mb_check_encoding( $string, 'ASCII' ) ) {
return true;
}
} elseif ( ! preg_match( '/[^\x00-\x7F]/', $string ) ) {
return true;
}
return false;
}
/**
* Check if the query is accessing a collation considered safe on the current version of MySQL.
*
* @since 4.2.0
*
* @param string $query The query to check.
* @return bool True if the collation is safe, false if it isn't.
*/
protected function check_safe_collation( $query ) {
if ( $this->checking_collation ) {
return true;
}
// We don't need to check the collation for queries that don't read data.
$query = ltrim( $query, "\r\n\t (" );
if ( preg_match( '/^(?:SHOW|DESCRIBE|DESC|EXPLAIN|CREATE)\s/i', $query ) ) {
return true;
}
// All-ASCII queries don't need extra checking.
if ( $this->check_ascii( $query ) ) {
return true;
}
$table = $this->get_table_from_query( $query );
if ( ! $table ) {
return false;
}
$this->checking_collation = true;
$collation = $this->get_table_charset( $table );
$this->checking_collation = false;
// Tables with no collation, or latin1 only, don't need extra checking.
if ( false === $collation || 'latin1' === $collation ) {
return true;
}
$table = strtolower( $table );
if ( empty( $this->col_meta[ $table ] ) ) {
return false;
}
// If any of the columns don't have one of these collations, it needs more sanity checking.
foreach ( $this->col_meta[ $table ] as $col ) {
if ( empty( $col->Collation ) ) {
continue;
}
if ( ! in_array( $col->Collation, array( 'utf8_general_ci', 'utf8_bin', 'utf8mb4_general_ci', 'utf8mb4_bin' ), true ) ) {
return false;
}
}
return true;
}
/**
* Strips any invalid characters based on value/charset pairs.
*
* @since 4.2.0
*
* @param array $data Array of value arrays. Each value array has the keys
* 'value' and 'charset'. An optional 'ascii' key can be
* set to false to avoid redundant ASCII checks.
* @return array|WP_Error The $data parameter, with invalid characters removed from
* each value. This works as a passthrough: any additional keys
* such as 'field' are retained in each value array. If we cannot
* remove invalid characters, a WP_Error object is returned.
*/
protected function strip_invalid_text( $data ) {
$db_check_string = false;
foreach ( $data as &$value ) {
$charset = $value['charset'];
if ( is_array( $value['length'] ) ) {
$length = $value['length']['length'];
$truncate_by_byte_length = 'byte' === $value['length']['type'];
} else {
$length = false;
// Since we have no length, we'll never truncate.
// Initialize the variable to false. true would take us
// through an unnecessary (for this case) codepath below.
$truncate_by_byte_length = false;
}
// There's no charset to work with.
if ( false === $charset ) {
continue;
}
// Column isn't a string.
if ( ! is_string( $value['value'] ) ) {
continue;
}
$needs_validation = true;
if (
// latin1 can store any byte sequence
'latin1' === $charset
||
// ASCII is always OK.
( ! isset( $value['ascii'] ) && $this->check_ascii( $value['value'] ) )
) {
$truncate_by_byte_length = true;
$needs_validation = false;
}
if ( $truncate_by_byte_length ) {
mbstring_binary_safe_encoding();
if ( false !== $length && strlen( $value['value'] ) > $length ) {
$value['value'] = substr( $value['value'], 0, $length );
}
reset_mbstring_encoding();
if ( ! $needs_validation ) {
continue;
}
}
// utf8 can be handled by regex, which is a bunch faster than a DB lookup.
if ( ( 'utf8' === $charset || 'utf8mb3' === $charset || 'utf8mb4' === $charset ) && function_exists( 'mb_strlen' ) ) {
$regex = '/
(
(?: [\x00-\x7F] # single-byte sequences 0xxxxxxx
| [\xC2-\xDF][\x80-\xBF] # double-byte sequences 110xxxxx 10xxxxxx
| \xE0[\xA0-\xBF][\x80-\xBF] # triple-byte sequences 1110xxxx 10xxxxxx * 2
| [\xE1-\xEC][\x80-\xBF]{2}
| \xED[\x80-\x9F][\x80-\xBF]
| [\xEE-\xEF][\x80-\xBF]{2}';
if ( 'utf8mb4' === $charset ) {
$regex .= '
| \xF0[\x90-\xBF][\x80-\xBF]{2} # four-byte sequences 11110xxx 10xxxxxx * 3
| [\xF1-\xF3][\x80-\xBF]{3}
| \xF4[\x80-\x8F][\x80-\xBF]{2}
';
}
$regex .= '){1,40} # ...one or more times
)
| . # anything else
/x';
$value['value'] = preg_replace( $regex, '$1', $value['value'] );
if ( false !== $length && mb_strlen( $value['value'], 'UTF-8' ) > $length ) {
$value['value'] = mb_substr( $value['value'], 0, $length, 'UTF-8' );
}
continue;
}
// We couldn't use any local conversions, send it to the DB.
$value['db'] = $db_check_string = true;
}
unset( $value ); // Remove by reference.
if ( $db_check_string ) {
$queries = array();
foreach ( $data as $col => $value ) {
if ( ! empty( $value['db'] ) ) {
// We're going to need to truncate by characters or bytes, depending on the length value we have.
if ( 'byte' === $value['length']['type'] ) {
// Using binary causes LEFT() to truncate by bytes.
$charset = 'binary';
} else {
$charset = $value['charset'];
}
if ( $this->charset ) {
$connection_charset = $this->charset;
} else {
if ( $this->use_mysqli ) {
$connection_charset = mysqli_character_set_name( $this->dbh );
} else {
$connection_charset = mysql_client_encoding();
}
}
if ( is_array( $value['length'] ) ) {
$length = sprintf( '%.0f', $value['length']['length'] );
$queries[ $col ] = $this->prepare( "CONVERT( LEFT( CONVERT( %s USING $charset ), $length ) USING $connection_charset )", $value['value'] );
} elseif ( 'binary' !== $charset ) {
// If we don't have a length, there's no need to convert binary - it will always return the same result.
$queries[ $col ] = $this->prepare( "CONVERT( CONVERT( %s USING $charset ) USING $connection_charset )", $value['value'] );
}
unset( $data[ $col ]['db'] );
}
}
$sql = array();
foreach ( $queries as $column => $query ) {
if ( ! $query ) {
continue;
}
$sql[] = $query . " AS x_$column";
}
$this->check_current_query = false;
$row = $this->get_row( 'SELECT ' . implode( ', ', $sql ), ARRAY_A );
if ( ! $row ) {
return new WP_Error( 'wpdb_strip_invalid_text_failure' );
}
foreach ( array_keys( $data ) as $column ) {
if ( isset( $row[ "x_$column" ] ) ) {
$data[ $column ]['value'] = $row[ "x_$column" ];
}
}
}
return $data;
}
/**
* Strips any invalid characters from the query.
*
* @since 4.2.0
*
* @param string $query Query to convert.
* @return string|WP_Error The converted query, or a WP_Error object if the conversion fails.
*/
protected function strip_invalid_text_from_query( $query ) {
// We don't need to check the collation for queries that don't read data.
$trimmed_query = ltrim( $query, "\r\n\t (" );
if ( preg_match( '/^(?:SHOW|DESCRIBE|DESC|EXPLAIN|CREATE)\s/i', $trimmed_query ) ) {
return $query;
}
$table = $this->get_table_from_query( $query );
if ( $table ) {
$charset = $this->get_table_charset( $table );
if ( is_wp_error( $charset ) ) {
return $charset;
}
// We can't reliably strip text from tables containing binary/blob columns
if ( 'binary' === $charset ) {
return $query;
}
} else {
$charset = $this->charset;
}
$data = array(
'value' => $query,
'charset' => $charset,
'ascii' => false,
'length' => false,
);
$data = $this->strip_invalid_text( array( $data ) );
if ( is_wp_error( $data ) ) {
return $data;
}
return $data[0]['value'];
}
/**
* Strips any invalid characters from the string for a given table and column.
*
* @since 4.2.0
*
* @param string $table Table name.
* @param string $column Column name.
* @param string $value The text to check.
* @return string|WP_Error The converted string, or a WP_Error object if the conversion fails.
*/
public function strip_invalid_text_for_column( $table, $column, $value ) {
if ( ! is_string( $value ) ) {
return $value;
}
$charset = $this->get_col_charset( $table, $column );
if ( ! $charset ) {
// Not a string column.
return $value;
} elseif ( is_wp_error( $charset ) ) {
// Bail on real errors.
return $charset;
}
$data = array(
$column => array(
'value' => $value,
'charset' => $charset,
'length' => $this->get_col_length( $table, $column ),
),
);
$data = $this->strip_invalid_text( $data );
if ( is_wp_error( $data ) ) {
return $data;
}
return $data[ $column ]['value'];
}
/**
* Find the first table name referenced in a query.
*
* @since 4.2.0
*
* @param string $query The query to search.
* @return string|false $table The table name found, or false if a table couldn't be found.
*/
protected function get_table_from_query( $query ) {
// Remove characters that can legally trail the table name.
$query = rtrim( $query, ';/-#' );
// Allow (select...) union [...] style queries. Use the first query's table name.
$query = ltrim( $query, "\r\n\t (" );
// Strip everything between parentheses except nested selects.
$query = preg_replace( '/\((?!\s*select)[^(]*?\)/is', '()', $query );
// Quickly match most common queries.
if ( preg_match(
'/^\s*(?:'
. 'SELECT.*?\s+FROM'
. '|INSERT(?:\s+LOW_PRIORITY|\s+DELAYED|\s+HIGH_PRIORITY)?(?:\s+IGNORE)?(?:\s+INTO)?'
. '|REPLACE(?:\s+LOW_PRIORITY|\s+DELAYED)?(?:\s+INTO)?'
. '|UPDATE(?:\s+LOW_PRIORITY)?(?:\s+IGNORE)?'
. '|DELETE(?:\s+LOW_PRIORITY|\s+QUICK|\s+IGNORE)*(?:.+?FROM)?'
. ')\s+((?:[0-9a-zA-Z$_.`-]|[\xC2-\xDF][\x80-\xBF])+)/is',
$query,
$maybe
) ) {
return str_replace( '`', '', $maybe[1] );
}
// SHOW TABLE STATUS and SHOW TABLES WHERE Name = 'wp_posts'
if ( preg_match( '/^\s*SHOW\s+(?:TABLE\s+STATUS|(?:FULL\s+)?TABLES).+WHERE\s+Name\s*=\s*("|\')((?:[0-9a-zA-Z$_.-]|[\xC2-\xDF][\x80-\xBF])+)\\1/is', $query, $maybe ) ) {
return $maybe[2];
}
// SHOW TABLE STATUS LIKE and SHOW TABLES LIKE 'wp\_123\_%'
// This quoted LIKE operand seldom holds a full table name.
// It is usually a pattern for matching a prefix so we just
// strip the trailing % and unescape the _ to get 'wp_123_'
// which drop-ins can use for routing these SQL statements.
if ( preg_match( '/^\s*SHOW\s+(?:TABLE\s+STATUS|(?:FULL\s+)?TABLES)\s+(?:WHERE\s+Name\s+)?LIKE\s*("|\')((?:[\\\\0-9a-zA-Z$_.-]|[\xC2-\xDF][\x80-\xBF])+)%?\\1/is', $query, $maybe ) ) {
return str_replace( '\\_', '_', $maybe[2] );
}
// Big pattern for the rest of the table-related queries.
if ( preg_match(
'/^\s*(?:'
. '(?:EXPLAIN\s+(?:EXTENDED\s+)?)?SELECT.*?\s+FROM'
. '|DESCRIBE|DESC|EXPLAIN|HANDLER'
. '|(?:LOCK|UNLOCK)\s+TABLE(?:S)?'
. '|(?:RENAME|OPTIMIZE|BACKUP|RESTORE|CHECK|CHECKSUM|ANALYZE|REPAIR).*\s+TABLE'
. '|TRUNCATE(?:\s+TABLE)?'
. '|CREATE(?:\s+TEMPORARY)?\s+TABLE(?:\s+IF\s+NOT\s+EXISTS)?'
. '|ALTER(?:\s+IGNORE)?\s+TABLE'
. '|DROP\s+TABLE(?:\s+IF\s+EXISTS)?'
. '|CREATE(?:\s+\w+)?\s+INDEX.*\s+ON'
. '|DROP\s+INDEX.*\s+ON'
. '|LOAD\s+DATA.*INFILE.*INTO\s+TABLE'
. '|(?:GRANT|REVOKE).*ON\s+TABLE'
. '|SHOW\s+(?:.*FROM|.*TABLE)'
. ')\s+\(*\s*((?:[0-9a-zA-Z$_.`-]|[\xC2-\xDF][\x80-\xBF])+)\s*\)*/is',
$query,
$maybe
) ) {
return str_replace( '`', '', $maybe[1] );
}
return false;
}
/**
* Load the column metadata from the last query.
*
* @since 3.5.0
*/
protected function load_col_info() {
if ( $this->col_info ) {
return;
}
if ( $this->use_mysqli ) {
$num_fields = mysqli_num_fields( $this->result );
for ( $i = 0; $i < $num_fields; $i++ ) {
$this->col_info[ $i ] = mysqli_fetch_field( $this->result );
}
} else {
$num_fields = mysql_num_fields( $this->result );
for ( $i = 0; $i < $num_fields; $i++ ) {
$this->col_info[ $i ] = mysql_fetch_field( $this->result, $i );
}
}
}
/**
* Retrieve column metadata from the last query.
*
* @since 0.71
*
* @param string $info_type Optional. Type one of name, table, def, max_length, not_null, primary_key, multiple_key, unique_key, numeric, blob, type, unsigned, zerofill
* @param int $col_offset Optional. 0: col name. 1: which table the col's in. 2: col's max length. 3: if the col is numeric. 4: col's type
* @return mixed Column Results
*/
public function get_col_info( $info_type = 'name', $col_offset = -1 ) {
$this->load_col_info();
if ( $this->col_info ) {
if ( $col_offset == -1 ) {
$i = 0;
$new_array = array();
foreach ( (array) $this->col_info as $col ) {
$new_array[ $i ] = $col->{$info_type};
$i++;
}
return $new_array;
} else {
return $this->col_info[ $col_offset ]->{$info_type};
}
}
}
/**
* Starts the timer, for debugging purposes.
*
* @since 1.5.0
*
* @return true
*/
public function timer_start() {
$this->time_start = microtime( true );
return true;
}
/**
* Stops the debugging timer.
*
* @since 1.5.0
*
* @return float Total time spent on the query, in seconds
*/
public function timer_stop() {
return ( microtime( true ) - $this->time_start );
}
/**
* Wraps errors in a nice header and footer and dies.
*
* Will not die if wpdb::$show_errors is false.
*
* @since 1.5.0
*
* @param string $message The Error message
* @param string $error_code Optional. A Computer readable string to identify the error.
* @return false|void
*/
public function bail( $message, $error_code = '500' ) {
if ( $this->show_errors ) {
$error = '';
if ( $this->use_mysqli ) {
if ( $this->dbh instanceof mysqli ) {
$error = mysqli_error( $this->dbh );
} elseif ( mysqli_connect_errno() ) {
$error = mysqli_connect_error();
}
} else {
if ( is_resource( $this->dbh ) ) {
$error = mysql_error( $this->dbh );
} else {
$error = mysql_error();
}
}
if ( $error ) {
$message = '<p><code>' . $error . "</code></p>\n" . $message;
}
wp_die( $message );
} else {
if ( class_exists( 'WP_Error', false ) ) {
$this->error = new WP_Error( $error_code, $message );
} else {
$this->error = $message;
}
return false;
}
}
/**
* Closes the current database connection.
*
* @since 4.5.0
*
* @return bool True if the connection was successfully closed, false if it wasn't,
* or the connection doesn't exist.
*/
public function close() {
if ( ! $this->dbh ) {
return false;
}
if ( $this->use_mysqli ) {
$closed = mysqli_close( $this->dbh );
} else {
$closed = mysql_close( $this->dbh );
}
if ( $closed ) {
$this->dbh = null;
$this->ready = false;
$this->has_connected = false;
}
return $closed;
}
/**
* Whether MySQL database is at least the required minimum version.
*
* @since 2.5.0
*
* @global string $wp_version
* @global string $required_mysql_version
*
* @return WP_Error|void
*/
public function check_database_version() {
global $wp_version, $required_mysql_version;
// Make sure the server has the required MySQL version
if ( version_compare( $this->db_version(), $required_mysql_version, '<' ) ) {
/* translators: 1: WordPress version number, 2: Minimum required MySQL version number */
return new WP_Error( 'database_version', sprintf( __( '<strong>ERROR</strong>: WordPress %1$s requires MySQL %2$s or higher' ), $wp_version, $required_mysql_version ) );
}
}
/**
* Whether the database supports collation.
*
* Called when WordPress is generating the table scheme.
*
* Use `wpdb::has_cap( 'collation' )`.
*
* @since 2.5.0
* @deprecated 3.5.0 Use wpdb::has_cap()
*
* @return bool True if collation is supported, false if version does not
*/
public function supports_collation() {
_deprecated_function( __FUNCTION__, '3.5.0', 'wpdb::has_cap( \'collation\' )' );
return $this->has_cap( 'collation' );
}
/**
* The database character collate.
*
* @since 3.5.0
*
* @return string The database character collate.
*/
public function get_charset_collate() {
$charset_collate = '';
if ( ! empty( $this->charset ) ) {
$charset_collate = "DEFAULT CHARACTER SET $this->charset";
}
if ( ! empty( $this->collate ) ) {
$charset_collate .= " COLLATE $this->collate";
}
return $charset_collate;
}
/**
* Determine if a database supports a particular feature.
*
* @since 2.7.0
* @since 4.1.0 Added support for the 'utf8mb4' feature.
* @since 4.6.0 Added support for the 'utf8mb4_520' feature.
*
* @see wpdb::db_version()
*
* @param string $db_cap The feature to check for. Accepts 'collation',
* 'group_concat', 'subqueries', 'set_charset',
* 'utf8mb4', or 'utf8mb4_520'.
* @return int|false Whether the database feature is supported, false otherwise.
*/
public function has_cap( $db_cap ) {
$version = $this->db_version();
switch ( strtolower( $db_cap ) ) {
case 'collation': // @since 2.5.0
case 'group_concat': // @since 2.7.0
case 'subqueries': // @since 2.7.0
return version_compare( $version, '4.1', '>=' );
case 'set_charset':
return version_compare( $version, '5.0.7', '>=' );
case 'utf8mb4': // @since 4.1.0
if ( version_compare( $version, '5.5.3', '<' ) ) {
return false;
}
if ( $this->use_mysqli ) {
$client_version = mysqli_get_client_info();
} else {
$client_version = mysql_get_client_info();
}
/*
* libmysql has supported utf8mb4 since 5.5.3, same as the MySQL server.
* mysqlnd has supported utf8mb4 since 5.0.9.
*/
if ( false !== strpos( $client_version, 'mysqlnd' ) ) {
$client_version = preg_replace( '/^\D+([\d.]+).*/', '$1', $client_version );
return version_compare( $client_version, '5.0.9', '>=' );
} else {
return version_compare( $client_version, '5.5.3', '>=' );
}
case 'utf8mb4_520': // @since 4.6.0
return version_compare( $version, '5.6', '>=' );
}
return false;
}
/**
* Retrieve the name of the function that called wpdb.
*
* Searches up the list of functions until it reaches
* the one that would most logically had called this method.
*
* @since 2.5.0
*
* @return string Comma separated list of the calling functions.
*/
public function get_caller() {
return wp_debug_backtrace_summary( __CLASS__ );
}
/**
* Retrieves the MySQL server version.
*
* @since 2.7.0
*
* @return null|string Null on failure, version number on success.
*/
public function db_version() {
if ( $this->use_mysqli ) {
$server_info = mysqli_get_server_info( $this->dbh );
} else {
$server_info = mysql_get_server_info( $this->dbh );
}
return preg_replace( '/[^0-9.].*/', '', $server_info );
}
}
Expand full source code Collapse full source code View on Trac
Changelog Changelog
| Version | Description |
|---|---|
| 0.71 | Introduced. |
Methods Methods
- __construct — Connects to the database server and selects a database
- __destruct — PHP5 style destructor and will run when database object is destroyed.
- __get — Makes private properties readable for backward compatibility.
- __isset — Makes private properties check-able for backward compatibility.
- __set — Makes private properties settable for backward compatibility.
- __unset — Makes private properties un-settable for backward compatibility.
- _do_query — Internal function to perform the mysql_query() call.
- _escape — Escape data. Works on arrays.
- _insert_replace_helper — Helper function for insert and replace.
- _real_escape — Real escape, using mysqli_real_escape_string() or mysql_real_escape_string()
- _weak_escape — Do not use, deprecated. — deprecated
- add_placeholder_escape — Adds a placeholder escape string, to escape anything that resembles a printf() placeholder.
- bail — Wraps errors in a nice header and footer and dies.
- check_ascii — Check if a string is ASCII.
- check_connection — Checks that the connection to the database is still up. If not, try to reconnect.
- check_database_version — Whether MySQL database is at least the required minimum version.
- check_safe_collation — Check if the query is accessing a collation considered safe on the current version of MySQL.
- close — Closes the current database connection.
- db_connect — Connect to and select database.
- db_version — Retrieves the MySQL server version.
- delete — Delete a row in the table
- determine_charset — Determines the best charset and collation to use given a charset and collation.
- esc_like — First half of escaping for LIKE special characters % and _ before preparing for MySQL.
- escape — Do not use, deprecated. — deprecated
- escape_by_ref — Escapes content by reference for insertion into the database, for security
- flush — Kill cached query results.
- get_blog_prefix — Gets blog prefix.
- get_caller — Retrieve the name of the function that called wpdb.
- get_charset_collate — The database character collate.
- get_col — Retrieve one column from the database.
- get_col_charset — Retrieves the character set for the given column.
- get_col_info — Retrieve column metadata from the last query.
- get_col_length — Retrieve the maximum string length allowed in a given column.
- get_results — Retrieve an entire SQL result set from the database (i.e., many rows)
- get_row — Retrieve one row from the database.
- get_table_charset — Retrieves the character set for the given table.
- get_table_from_query — Find the first table name referenced in a query.
- get_var — Retrieve one variable from the database.
- has_cap — Determine if a database supports a particular feature.
- hide_errors — Disables showing of database errors.
- init_charset — Set $this->charset and $this->collate
- insert — Insert a row into a table.
- load_col_info — Load the column metadata from the last query.
- parse_db_host — Parse the DB_HOST setting to interpret it for mysqli_real_connect.
- placeholder_escape — Generates and returns a placeholder escape string for use in queries returned by ::prepare().
- prepare — Prepares a SQL query for safe execution. Uses sprintf()-like syntax.
- print_error — Print SQL/DB error.
- process_field_charsets — Adds field charsets to field/value/format arrays generated by the wpdb::process_field_formats() method.
- process_field_formats — Prepares arrays of value/format pairs as passed to wpdb CRUD methods.
- process_field_lengths — For string fields, record the maximum string length that field can safely save.
- process_fields — Processes arrays of field/value pairs and field formats.
- query — Perform a MySQL database query, using current database connection.
- remove_placeholder_escape — Removes the placeholder escape strings from a query.
- replace — Replace a row into a table.
- select — Selects a database using the current database connection.
- set_blog_id — Sets blog id.
- set_charset — Sets the connection's character set.
- set_prefix — Sets the table prefix for the WordPress tables.
- set_sql_mode — Change the current SQL mode, and ensure its WordPress compatibility.
- show_errors — Enables showing of database errors.
- strip_invalid_text — Strips any invalid characters based on value/charset pairs.
- strip_invalid_text_for_column — Strips any invalid characters from the string for a given table and column.
- strip_invalid_text_from_query — Strips any invalid characters from the query.
- supports_collation — Whether the database supports collation. — deprecated
- suppress_errors — Whether to suppress database errors.
- tables — Returns an array of WordPress tables.
- timer_start — Starts the timer, for debugging purposes.
- timer_stop — Stops the debugging timer.
- update — Update a row in the table
User Contributed Notes User Contributed Notes
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Retrieve and display the sum of a Custom Field value.
// set the meta_key to the appropriate custom field meta key $meta_key = 'miles'; $allmiles = $wpdb->get_var( $wpdb->prepare( " SELECT sum(meta_value) FROM $wpdb->postmeta WHERE meta_key = %s ", $meta_key ) ); echo "<p>Total miles is {$allmiles}</p>";Sync Server timezone with MYSQL timezone
date_default_timezone_set('Europe/London'); $wpdb->time_zone = 'Europe/London';