get_meta_sql() │ WP 3.2.0

Creates the JOIN and WHERE parts of the SQL query for metadata based on the provided parameters, which can be used in the main query.

This is a wrapper for the class WP_Meta_Query.

No Hooks.

Returns

String[]|false. An associative array with JOIN and WHERE keys:

array(
	'join'  => 'JOIN SQL string',
	'where' => 'WHERE SQL string'
)

Usage

get_meta_sql( $meta_query, $type, $primary_table, $primary_id_column, $context );

$meta_query(array) (required)

Query parameters. See the description of WP_Meta_Query.

$type(string) (required)

Type of metadata. For example: 'user', 'post', 'comment'.
A table with the name $type .'meta' must be registered in the $wpdb object, for example, if we specify 'foo' here, then the table $wpdb->foometa must exist. If such a table does not exist, this class will not work!

$primary_table(string) (required)

Name of the primary table to which the metadata table relates. For example wp_posts, wp_comments, wp_users.

$primary_id_column(string) (required)

Name of the key column of the primary table specified in $primary_table. For wp_posts - ID, for wp_users - ID, for wp_comments - comment_ID.

$context(object)

Object of the main query. This parameter is not used anywhere and is passed to the filter get_meta_sql.
Default: null

Examples

$meta_query = array(
	array(
		'key'     => 'key_name',
		'value' => 'field value',
		'compare' => '=' // optional, default is '=' or 'IN' (if value is an array)
	)
);

$mq_sql = get_meta_sql( $meta_query, 'post', 'wp_posts', 'ID' );

Array
(
	[join] =>  INNER JOIN wp_postmeta ON ( wp_posts.ID = wp_postmeta.post_id )
	[where] =>  AND (
		( wp_postmeta.meta_key = 'key_name' AND CAST(wp_postmeta.meta_value AS CHAR) = 'field value' )
	)
)

Add Your Own Example