Below is the database class for using in your PHP project
'%d'
*
*/
var $field_types = array();
/**
* Database table columns charset
*/
var $charset;
/**
* Database table columns collate
*/
var $collate;
/**
* Database Username
*/
protected $dbuser;
/**
* Database Password
*/
protected $dbpassword;
/**
* Database Name
*/
protected $dbname;
/**
* Database Host
*/
protected $dbhost;
/**
* Database Handle
*/
protected $dbh;
/**
* A textual description of the last query/get_row/get_var call
*/
var $func_call;
/**
* Whether MySQL is used as the database engine.
*
* Set in WPDB::db_connect() to true, by default.
*/
public $is_mysql = null;
/**
* A list of incompatible SQL modes.
*/
protected $incompatible_modes = array( 'NO_ZERO_DATE', 'ONLY_FULL_GROUP_BY',
'STRICT_TRANS_TABLES', 'STRICT_ALL_TABLES', 'TRADITIONAL' );
/**
* Whether to use mysqli over mysql.
*/
private $use_mysqli = false;
/**
* Whether we've managed to successfully connect at some point
*/
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.
*
* @param string $dbuser MySQL database user
* @param string $dbpassword MySQL database password
* @param string $dbname MySQL database name
* @param string $dbhost MySQL database host
*/
function __construct( $dbuser = DB_USER, $dbpassword = DB_PASSWORD, $dbname = DB_NAME, $dbhost = DB_HOST ) {
if( empty($dbuser) || empty($dbname) || empty($dbhost) )
$this->bail( "Please set the database details in wp-db.php" );
register_shutdown_function( array( $this, '__destruct' ) );
if ( WP_DEBUG && WP_DEBUG_DISPLAY )
$this->show_errors();
/* Use ext/mysqli if it exists and:
* - WP_USE_EXT_MYSQL is defined as false, or
* - We are a development version of WordPress, or
* - We are running PHP 5.5 or greater, or
* - ext/mysql is not loaded.
*/
if ( function_exists( 'mysqli_connect' ) ) {
if ( defined( 'WP_USE_EXT_MYSQL' ) ) {
$this->use_mysqli = ! WP_USE_EXT_MYSQL;
} elseif ( version_compare( phpversion(), '5.5', '>=' ) || ! function_exists( 'mysql_connect' ) ) {
$this->use_mysqli = true;
}
}
$this->init_charset();
$this->dbuser = $dbuser;
$this->dbpassword = $dbpassword;
$this->dbname = $dbname;
$this->dbhost = $dbhost;
$this->db_connect();
}
/**
* PHP5 style destructor and will run when database object is destroyed.
* @return bool true
*/
function __destruct() {
return true;
}
/**
* PHP5 style magic getter, used to lazy-load expensive data.
* @param string $name The private member to get, and optionally process
* @return mixed The private member
*/
function __get( $name ) {
if ( 'col_info' == $name )
$this->load_col_info();
return $this->$name;
}
/**
* Magic function, for backwards compatibility
* @param string $name The private member to set
* @param mixed $value The value to set
*/
function __set( $name, $value ) {
$this->$name = $value;
}
/**
* Magic function, for backwards compatibility
* @param string $name The private member to check
*
* @return bool If the member is set or not
*/
function __isset( $name ) {
return isset( $this->$name );
}
/**
* Magic function, for backwards compatibility
* @param string $name The private member to unset
*/
function __unset( $name ) {
unset( $this->$name );
}
/**
* Set $this->charset and $this->collate
*/
function init_charset() {
if ( defined( 'DB_COLLATE' ) )
$this->collate = DB_COLLATE;
if ( defined( 'DB_CHARSET' ) )
$this->charset = DB_CHARSET;
}
/**
* Sets the connection's character set.
* @param resource $dbh The resource given by mysql_connect
* @param string $charset The character set (optional)
* @param string $collate The collation (optional)
*/
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 ) ) {
if ( $this->use_mysqli ) {
if ( function_exists( 'mysqli_set_charset' ) && $this->has_cap( 'set_charset' ) ) {
mysqli_set_charset( $dbh, $charset );
} else {
$query = $this->prepare( 'SET NAMES %s', $charset );
if ( ! empty( $collate ) )
$query .= $this->prepare( ' COLLATE %s', $collate );
mysqli_query( $query, $dbh );
}
} else {
if ( function_exists( 'mysql_set_charset' ) && $this->has_cap( 'set_charset' ) ) {
mysql_set_charset( $charset, $dbh );
} else {
$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.
*/
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 );
/**
* Filter the list of incompatible SQL modes to exclude.
*/
$incompatible_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 );
}
}
/**
* 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.
* @param string $db MySQL database name
* @param resource $dbh Optional link identifier.
* @return null Always null.
*/
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;
$this->bail( "Unable to connect to database" );
return;
}
}
/**
* Real escape, using mysql_real_escape_string()
* @param string $string to escape
* @return string escaped
*/
function _real_escape( $string ) {
if ( $this->dbh ) {
if ( $this->use_mysqli ) {
return mysqli_real_escape_string( $this->dbh, $string );
} else {
return mysql_real_escape_string( $string, $this->dbh );
}
}
$class = get_class( $this );
$this->bail("$class must set a database connection for use with escaping.");
return;
}
/**
* Escape data. Works on arrays.
* @param string|array $data
* @return string|array escaped
*/
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;
}
/**
* Escapes content by reference for insertion into the database, for security
* @param string $string to escape
* @return void
*/
function escape_by_ref( &$string ) {
if ( ! is_float( $string ) )
$string = $this->_real_escape( $string );
}
/**
* Prepares a SQL query for safe execution. Uses sprintf()-like syntax.
*
* The following directives can be used in the query format string:
* %d (integer)
* %f (float)
* %s (string)
* %% (literal percentage sign - no argument needed)
*
* All of %d, %f, and %s are to be left unquoted in the query string and they need an argument passed for them.
* Literals (%) as parts of the query must be properly written as %%.
*
* This function only supports a small subset of the sprintf syntax; it only supports %d (integer), %f (float), and %s (string).
* Does not support sign, padding, alignment, width or precision specifiers.
* Does not support argument numbering/swapping.
*
* May be called like {@link http://php.net/sprintf sprintf()} or like {@link http://php.net/vsprintf vsprintf()}.
*
* Both %d and %s should be left unquoted in the query string.
*
*
* wpdb::prepare( "SELECT * FROM `table` WHERE `column` = %s AND `field` = %d", 'foo', 1337 )
* wpdb::prepare( "SELECT DATE_FORMAT(`field`, '%%c') FROM `table` WHERE `column` = %s", 'foo' );
*
*
* @link http://php.net/sprintf Description of syntax.
*
* @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 like
* {@link http://php.net/vsprintf vsprintf()}, or the first variable to substitute into the query's placeholders if
* being called like {@link http://php.net/sprintf sprintf()}.
* @param mixed $args,... further variables to substitute into the query's placeholders if being called like
* {@link http://php.net/sprintf sprintf()}.
* @return null|false|string Sanitized query string, null if there is no query, false if there is an error and string
* if there was something to prepare
*/
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 ) {
$this->bail( 'The query argument of prepare must have a placeholder.' );
}
$args = func_get_args();
array_shift( $args );
// If args were passed as an array (as in vsprintf), move them up
if ( isset( $args[0] ) && is_array($args[0]) )
$args = $args[0];
$query = str_replace( "'%s'", '%s', $query ); // in case someone mistakenly already singlequoted it
$query = str_replace( '"%s"', '%s', $query ); // doublequote unquoting
$query = preg_replace( '|(?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;
if ( $caller = $this->get_caller() )
$error_str = sprintf( 'WordPress database error %1$s for query %2$s made by %3$s', $str, $this->last_query, $caller );
else
$error_str = sprintf( 'WordPress database error %1$s for query %2$s', $str, $this->last_query );
error_log( $error_str );
// Are we showing errors?
if ( ! $this->show_errors )
return false;
$str = htmlspecialchars( $str, ENT_QUOTES );
$query = htmlspecialchars( $this->last_query, ENT_QUOTES );
print "
WordPress database error: [$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.
*
* @param bool $show Whether to show or hide errors
* @return bool Old value for showing errors.
*/
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.
* @return bool Whether showing of errors was active
*/
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.
* @param bool $suppress Optional. New value. Defaults to true.
* @return bool Old value
*/
function suppress_errors( $suppress = true ) {
$errors = $this->suppress_errors;
$this->suppress_errors = (bool) $suppress;
return $errors;
}
/**
* Kill cached query results.
* @return void
*/
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 ( is_resource( $this->result ) ) {
if ( $this->use_mysqli ) {
mysqli_free_result( $this->result );
} else {
mysql_free_result( $this->result );
}
}
}
/**
* Connect to and select database
*/
function db_connect( $allow_bail = true ) {
$this->is_mysql = true;
$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();
// 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.
$port = null;
$socket = null;
$host = $this->dbhost;
$port_or_socket = strstr( $host, ':' );
if ( ! empty( $port_or_socket ) ) {
$host = substr( $host, 0, strpos( $host, ':' ) );
$port_or_socket = substr( $port_or_socket, 1 );
if ( 0 !== strpos( $port_or_socket, '/' ) ) {
$port = intval( $port_or_socket );
$maybe_socket = strstr( $port_or_socket, ':' );
if ( ! empty( $maybe_socket ) ) {
$socket = substr( $maybe_socket, 1 );
}
} else {
$socket = $port_or_socket;
}
}
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;
} else if ( defined( 'WP_USE_EXT_MYSQL' ) && ! WP_USE_EXT_MYSQL ) {
$attempt_fallback = false;
} else if ( ! function_exists( 'mysql_connect' ) ) {
$attempt_fallback = false;
}
if ( $attempt_fallback ) {
$this->use_mysqli = false;
$this->db_connect();
}
}
} 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 ) {
$this->bail( "
Error establishing a database connection
This either means that the username and password information is incorrect or we can't contact the database server. This could mean your host's database server is down.
This means that we lost contact with the database server. This could mean your host's database server is down.
* wpdb::insert( 'table', array( 'column' => 'foo', 'field' => 'bar' ) )
* wpdb::insert( 'table', array( 'column' => 'foo', 'field' => 1337 ), array( '%s', '%d' ) )
*
*
* @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).
* @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.
*/
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' ) )
*
*
* @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).
* @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.
*/
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.
*
* @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).
* @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' ) {
if ( ! in_array( strtoupper( $type ), array( 'REPLACE', 'INSERT' ) ) )
return false;
$this->insert_id = 0;
$formats = $format = (array) $format;
$fields = array_keys( $data );
$formatted_fields = array();
foreach ( $fields as $field ) {
if ( !empty( $format ) )
$form = ( $form = array_shift( $formats ) ) ? $form : $format[0];
elseif ( isset( $this->field_types[$field] ) )
$form = $this->field_types[$field];
else
$form = '%s';
$formatted_fields[] = $form;
}
$sql = "{$type} INTO `$table` (`" . implode( '`,`', $fields ) . "`) VALUES (" . implode( ",", $formatted_fields ) . ")";
return $this->query( $this->prepare( $sql, $data ) );
}
/**
* 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' ) )
*
*
* @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).
* @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".
* @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.
*/
function update( $table, $data, $where, $format = null, $where_format = null ) {
if ( ! is_array( $data ) || ! is_array( $where ) )
return false;
$formats = $format = (array) $format;
$bits = $wheres = array();
foreach ( (array) array_keys( $data ) as $field ) {
if ( !empty( $format ) )
$form = ( $form = array_shift( $formats ) ) ? $form : $format[0];
elseif ( isset($this->field_types[$field]) )
$form = $this->field_types[$field];
else
$form = '%s';
$bits[] = "`$field` = {$form}";
}
$where_formats = $where_format = (array) $where_format;
foreach ( (array) array_keys( $where ) as $field ) {
if ( !empty( $where_format ) )
$form = ( $form = array_shift( $where_formats ) ) ? $form : $where_format[0];
elseif ( isset( $this->field_types[$field] ) )
$form = $this->field_types[$field];
else
$form = '%s';
$wheres[] = "`$field` = {$form}";
}
$sql = "UPDATE `$table` SET " . implode( ', ', $bits ) . ' WHERE ' . implode( ' AND ', $wheres );
return $this->query( $this->prepare( $sql, array_merge( array_values( $data ), array_values( $where ) ) ) );
}
/**
* Delete a row in the table
*
*
* wpdb::delete( 'table', array( 'ID' => 1 ) )
* wpdb::delete( 'table', array( 'ID' => 1 ), array( '%d' ) )
*
*
* @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".
* @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.
*/
function delete( $table, $where, $where_format = null ) {
if ( ! is_array( $where ) )
return false;
$bits = $wheres = array();
$where_formats = $where_format = (array) $where_format;
foreach ( array_keys( $where ) as $field ) {
if ( !empty( $where_format ) ) {
$form = ( $form = array_shift( $where_formats ) ) ? $form : $where_format[0];
} elseif ( isset( $this->field_types[ $field ] ) ) {
$form = $this->field_types[ $field ];
} else {
$form = '%s';
}
$wheres[] = "$field = $form";
}
$sql = "DELETE FROM $table WHERE " . implode( ' AND ', $wheres );
return $this->query( $this->prepare( $sql, $where ) );
}
/**
* 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.
*
* @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
*/
function get_var( $query = null, $x = 0, $y = 0 ) {
$this->func_call = "\$db->get_var(\"$query\", $x, $y)";
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.
*
* @param string|null $query SQL query.
* @param string $output Optional. one of ARRAY_A | ARRAY_N | OBJECT constants. Return an associative array (column => value, ...),
* a numerically indexed array (0 => value, ...) or an object ( ->column = value ), respectively.
* @param int $y Optional. Row to return. Indexed from 0.
* @return mixed Database query result in format specified by $output or null on failure
*/
function get_row( $query = null, $output = OBJECT, $y = 0 ) {
$this->func_call = "\$db->get_row(\"$query\",$output,$y)";
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.
*
* @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.
*/
function get_col( $query = null , $x = 0 ) {
if ( $query )
$this->query( $query );
$new_array = array();
// Extract the column values
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.
*
* @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 mixed Database query results
*/
function get_results( $query = null, $output = OBJECT ) {
$this->func_call = "\$db->get_results(\"$query\", $output)";
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)
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;
}
/**
* Load the column metadata from the last query.
*
* @access protected
*/
protected function load_col_info() {
if ( $this->col_info )
return;
if ( $this->use_mysqli ) {
for ( $i = 0; $i < @mysqli_num_fields( $this->result ); $i++ ) {
$this->col_info[ $i ] = @mysqli_fetch_field( $this->result );
}
} else {
for ( $i = 0; $i < @mysql_num_fields( $this->result ); $i++ ) {
$this->col_info[ $i ] = @mysql_fetch_field( $this->result, $i );
}
}
}
/**
* Retrieve column metadata from the last query.
*
* @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
*/
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.
*
* @return true
*/
function timer_start() {
$this->time_start = microtime( true );
return true;
}
/**
* Stops the debugging timer.
*
* @return float Total time spent on the query, in seconds
*/
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.
*
* @param string $message The Error message
* @return false|void
*/
function bail( $message) {
if ( !$this->show_errors ) {
$this->error = $message;
return false;
}
die($message);
}
/**
* Whether MySQL database is at least the required minimum version.
*
* @return WP_Error
*/
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(), $required_mysql_version, '<') )
return new WP_Error('database_version', sprintf( __( 'ERROR: WordPress %1$s requires MySQL %2$s or higher' ), $wp_version, $required_mysql_version ));
}
/**
* Whether the database supports collation.
*
* @since 2.5.0
* @deprecated 3.5.0
* @deprecated Use wpdb::has_cap( 'collation' )
*
* @return bool True if collation is supported, false if version does not
*/
function supports_collation() {
_deprecated_function( __FUNCTION__, '3.5', 'wpdb::has_cap( \'collation\' )' );
return $this->has_cap( 'collation' );
}
/**
* The database character collate.
*
* @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.
*
* @param string $db_cap The feature to check for.
* @return bool
*/
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', '>=' );
};
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.
*
* @return string The name of the calling function
*/
function get_caller() {
return $this->debug_backtrace_summary( __CLASS__ );
}
function debug_backtrace_summary( $ignore_class = null, $skip_frames = 0, $pretty = true ) {
if ( version_compare( PHP_VERSION, '5.2.5', '>=' ) )
$trace = debug_backtrace( false );
else
$trace = debug_backtrace();
$caller = array();
$check_class = ! is_null( $ignore_class );
$skip_frames++; // skip this function
foreach ( $trace as $call ) {
if ( $skip_frames > 0 ) {
$skip_frames--;
}
elseif ( isset( $call['class'] ) ) {
if ( $check_class && $ignore_class == $call['class'] )
continue; // Filter out calls
$caller[] = "{$call['class']}{$call['type']}{$call['function']}";
}
else {
$caller[] = $call['function'];
}
}
if ( $pretty )
return join( ', ', array_reverse( $caller ) );
else
return $caller;
}
/**
* The database version number.
*
* @return false|string false on failure, version number on success
*/
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 );
}
}
//Create an object of the wpdb class
$wpdb = new wpdb();