web/wp-includes/meta.php
changeset 194 32102edaa81b
parent 136 bde1974c263b
child 204 09a1c134465b
--- a/web/wp-includes/meta.php	Thu Sep 16 15:45:36 2010 +0000
+++ b/web/wp-includes/meta.php	Mon Nov 19 18:26:13 2012 +0100
@@ -1,18 +1,40 @@
 <?php
 /**
- * Meta API
+ * Metadata API
  *
- * Functions for retrieving and manipulating metadata
+ * Functions for retrieving and manipulating metadata of various WordPress object types. Metadata
+ * for an object is a represented by a simple key-value pair. Objects may contain multiple
+ * metadata entries that share the same key and differ only in their value.
  *
  * @package WordPress
  * @subpackage Meta
  * @since 2.9.0
  */
 
+/**
+ * Add metadata for the specified object.
+ *
+ * @since 2.9.0
+ * @uses $wpdb WordPress database object for queries.
+ * @uses do_action() Calls 'added_{$meta_type}_meta' with meta_id of added metadata entry,
+ * 		object ID, meta key, and meta value
+ *
+ * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
+ * @param int $object_id ID of the object metadata is for
+ * @param string $meta_key Metadata key
+ * @param string $meta_value Metadata value
+ * @param bool $unique Optional, default is false. Whether the specified metadata key should be
+ * 		unique for the object. If true, and the object already has a value for the specified
+ * 		metadata key, no change will be made
+ * @return bool The meta ID on successful update, false on failure.
+ */
 function add_metadata($meta_type, $object_id, $meta_key, $meta_value, $unique = false) {
 	if ( !$meta_type || !$meta_key )
 		return false;
 
+	if ( !$object_id = absint($object_id) )
+		return false;
+
 	if ( ! $table = _get_meta_table($meta_type) )
 		return false;
 
@@ -22,31 +44,67 @@
 
 	// expected_slashed ($meta_key)
 	$meta_key = stripslashes($meta_key);
+	$meta_value = stripslashes_deep($meta_value);
+	$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type );
+
+	$check = apply_filters( "add_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $unique );
+	if ( null !== $check )
+		return $check;
 
 	if ( $unique && $wpdb->get_var( $wpdb->prepare(
 		"SELECT COUNT(*) FROM $table WHERE meta_key = %s AND $column = %d",
 		$meta_key, $object_id ) ) )
 		return false;
 
-	$meta_value = maybe_serialize( stripslashes_deep($meta_value) );
+	$_meta_value = $meta_value;
+	$meta_value = maybe_serialize( $meta_value );
 
-	$wpdb->insert( $table, array(
+	do_action( "add_{$meta_type}_meta", $object_id, $meta_key, $_meta_value );
+
+	$result = $wpdb->insert( $table, array(
 		$column => $object_id,
 		'meta_key' => $meta_key,
 		'meta_value' => $meta_value
 	) );
 
+	if ( ! $result )
+		return false;
+
+	$mid = (int) $wpdb->insert_id;
+
 	wp_cache_delete($object_id, $meta_type . '_meta');
 
-	do_action( "added_{$meta_type}_meta", $wpdb->insert_id, $object_id, $meta_key, $meta_value );
+	do_action( "added_{$meta_type}_meta", $mid, $object_id, $meta_key, $_meta_value );
 
-	return true;
+	return $mid;
 }
 
+/**
+ * Update metadata for the specified object. If no value already exists for the specified object
+ * ID and metadata key, the metadata will be added.
+ *
+ * @since 2.9.0
+ * @uses $wpdb WordPress database object for queries.
+ * @uses do_action() Calls 'update_{$meta_type}_meta' before updating metadata with meta_id of
+ * 		metadata entry to update, object ID, meta key, and meta value
+ * @uses do_action() Calls 'updated_{$meta_type}_meta' after updating metadata with meta_id of
+ * 		updated metadata entry, object ID, meta key, and meta value
+ *
+ * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
+ * @param int $object_id ID of the object metadata is for
+ * @param string $meta_key Metadata key
+ * @param string $meta_value Metadata value
+ * @param string $prev_value Optional. If specified, only update existing metadata entries with
+ * 		the specified value. Otherwise, update all entries.
+ * @return bool True on successful update, false on failure.
+ */
 function update_metadata($meta_type, $object_id, $meta_key, $meta_value, $prev_value = '') {
 	if ( !$meta_type || !$meta_key )
 		return false;
 
+	if ( !$object_id = absint($object_id) )
+		return false;
+
 	if ( ! $table = _get_meta_table($meta_type) )
 		return false;
 
@@ -57,11 +115,28 @@
 
 	// expected_slashed ($meta_key)
 	$meta_key = stripslashes($meta_key);
+	$passed_value = $meta_value;
+	$meta_value = stripslashes_deep($meta_value);
+	$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type );
+
+	$check = apply_filters( "update_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $prev_value );
+	if ( null !== $check )
+		return (bool) $check;
 
 	if ( ! $meta_id = $wpdb->get_var( $wpdb->prepare( "SELECT $id_column FROM $table WHERE meta_key = %s AND $column = %d", $meta_key, $object_id ) ) )
-		return add_metadata($meta_type, $object_id, $meta_key, $meta_value);
+		return add_metadata($meta_type, $object_id, $meta_key, $passed_value);
 
-	$meta_value = maybe_serialize( stripslashes_deep($meta_value) );
+	// Compare existing value to new value if no prev value given and the key exists only once.
+	if ( empty($prev_value) ) {
+		$old_value = get_metadata($meta_type, $object_id, $meta_key);
+		if ( count($old_value) == 1 ) {
+			if ( $old_value[0] === $meta_value )
+				return false;
+		}
+	}
+
+	$_meta_value = $meta_value;
+	$meta_value = maybe_serialize( $meta_value );
 
 	$data  = compact( 'meta_value' );
 	$where = array( $column => $object_id, 'meta_key' => $meta_key );
@@ -71,18 +146,46 @@
 		$where['meta_value'] = $prev_value;
 	}
 
-	do_action( "update_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $meta_value );
+	do_action( "update_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
+
+	if ( 'post' == $meta_type )
+		do_action( 'update_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
 
 	$wpdb->update( $table, $data, $where );
+
 	wp_cache_delete($object_id, $meta_type . '_meta');
 
-	do_action( "updated_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $meta_value );
+	do_action( "updated_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
+
+	if ( 'post' == $meta_type )
+		do_action( 'updated_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
 
 	return true;
 }
 
+/**
+ * Delete metadata for the specified object.
+ *
+ * @since 2.9.0
+ * @uses $wpdb WordPress database object for queries.
+ * @uses do_action() Calls 'deleted_{$meta_type}_meta' after deleting with meta_id of
+ * 		deleted metadata entries, object ID, meta key, and meta value
+ *
+ * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
+ * @param int $object_id ID of the object metadata is for
+ * @param string $meta_key Metadata key
+ * @param string $meta_value Optional. Metadata value. If specified, only delete metadata entries
+ * 		with this value. Otherwise, delete all entries with the specified meta_key.
+ * @param bool $delete_all Optional, default is false. If true, delete matching metadata entries
+ * 		for all objects, ignoring the specified object_id. Otherwise, only delete matching
+ * 		metadata entries for the specified object_id.
+ * @return bool True on successful delete, false on failure.
+ */
 function delete_metadata($meta_type, $object_id, $meta_key, $meta_value = '', $delete_all = false) {
-	if ( !$meta_type || !$meta_key || (!$delete_all && ! (int)$object_id) )
+	if ( !$meta_type || !$meta_key )
+		return false;
+
+	if ( (!$object_id = absint($object_id)) && !$delete_all )
 		return false;
 
 	if ( ! $table = _get_meta_table($meta_type) )
@@ -94,7 +197,14 @@
 	$id_column = 'user' == $meta_type ? 'umeta_id' : 'meta_id';
 	// expected_slashed ($meta_key)
 	$meta_key = stripslashes($meta_key);
-	$meta_value = maybe_serialize( stripslashes_deep($meta_value) );
+	$meta_value = stripslashes_deep($meta_value);
+
+	$check = apply_filters( "delete_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $delete_all );
+	if ( null !== $check )
+		return (bool) $check;
+
+	$_meta_value = $meta_value;
+	$meta_value = maybe_serialize( $meta_value );
 
 	$query = $wpdb->prepare( "SELECT $id_column FROM $table WHERE meta_key = %s", $meta_key );
 
@@ -108,6 +218,15 @@
 	if ( !count( $meta_ids ) )
 		return false;
 
+	if ( $delete_all )
+		$object_ids = $wpdb->get_col( $wpdb->prepare( "SELECT $type_column FROM $table WHERE meta_key = %s", $meta_key ) );
+
+	do_action( "delete_{$meta_type}_meta", $meta_ids, $object_id, $meta_key, $_meta_value );
+
+	// Old-style action.
+	if ( 'post' == $meta_type )
+		do_action( 'delete_postmeta', $meta_ids );
+
 	$query = "DELETE FROM $table WHERE $id_column IN( " . implode( ',', $meta_ids ) . " )";
 
 	$count = $wpdb->query($query);
@@ -115,33 +234,66 @@
 	if ( !$count )
 		return false;
 
-	wp_cache_delete($object_id, $meta_type . '_meta');
+	if ( $delete_all ) {
+		foreach ( (array) $object_ids as $o_id ) {
+			wp_cache_delete($o_id, $meta_type . '_meta');
+		}
+	} else {
+		wp_cache_delete($object_id, $meta_type . '_meta');
+	}
 
-	do_action( "deleted_{$meta_type}_meta", $meta_ids, $object_id, $meta_key, $meta_value );
+	do_action( "deleted_{$meta_type}_meta", $meta_ids, $object_id, $meta_key, $_meta_value );
+
+	// Old-style action.
+	if ( 'post' == $meta_type )
+		do_action( 'deleted_postmeta', $meta_ids );
 
 	return true;
 }
 
+/**
+ * Retrieve metadata for the specified object.
+ *
+ * @since 2.9.0
+ *
+ * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
+ * @param int $object_id ID of the object metadata is for
+ * @param string $meta_key Optional. Metadata key. If not specified, retrieve all metadata for
+ * 		the specified object.
+ * @param bool $single Optional, default is false. If true, return only the first value of the
+ * 		specified meta_key. This parameter has no effect if meta_key is not specified.
+ * @return string|array Single metadata value, or array of values
+ */
 function get_metadata($meta_type, $object_id, $meta_key = '', $single = false) {
 	if ( !$meta_type )
 		return false;
 
+	if ( !$object_id = absint($object_id) )
+		return false;
+
+	$check = apply_filters( "get_{$meta_type}_metadata", null, $object_id, $meta_key, $single );
+	if ( null !== $check ) {
+		if ( $single && is_array( $check ) )
+			return $check[0];
+		else
+			return $check;
+	}
+
 	$meta_cache = wp_cache_get($object_id, $meta_type . '_meta');
 
 	if ( !$meta_cache ) {
-		update_meta_cache($meta_type, $object_id);
-		$meta_cache = wp_cache_get($object_id, $meta_type . '_meta');
+		$meta_cache = update_meta_cache( $meta_type, array( $object_id ) );
+		$meta_cache = $meta_cache[$object_id];
 	}
 
-	if ( ! $meta_key )
+	if ( !$meta_key )
 		return $meta_cache;
 
 	if ( isset($meta_cache[$meta_key]) ) {
-		if ( $single ) {
+		if ( $single )
 			return maybe_unserialize( $meta_cache[$meta_key][0] );
-		} else {
+		else
 			return array_map('maybe_unserialize', $meta_cache[$meta_key]);
-		}
 	}
 
 	if ($single)
@@ -150,6 +302,225 @@
 		return array();
 }
 
+/**
+ * Determine if a meta key is set for a given object
+ *
+ * @since 3.3.0
+ *
+ * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
+ * @param int $object_id ID of the object metadata is for
+ * @param string $meta_key Metadata key.
+ * @return boolean true of the key is set, false if not.
+ */
+function metadata_exists( $meta_type, $object_id, $meta_key ) {
+	if ( ! $meta_type )
+		return false;
+
+	if ( ! $object_id = absint( $object_id ) )
+		return false;
+
+	$check = apply_filters( "get_{$meta_type}_metadata", null, $object_id, $meta_key, true );
+	if ( null !== $check )
+		return true;
+
+	$meta_cache = wp_cache_get( $object_id, $meta_type . '_meta' );
+
+	if ( !$meta_cache ) {
+		$meta_cache = update_meta_cache( $meta_type, array( $object_id ) );
+		$meta_cache = $meta_cache[$object_id];
+	}
+
+	if ( isset( $meta_cache[ $meta_key ] ) )
+		return true;
+
+	return false;
+}
+
+/**
+ * Get meta data by meta ID
+ *
+ * @since 3.3.0
+ *
+ * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
+ * @param int $meta_id ID for a specific meta row
+ * @return object Meta object or false.
+ */
+function get_metadata_by_mid( $meta_type, $meta_id ) {
+	global $wpdb;
+
+	if ( ! $meta_type )
+		return false;
+
+	if ( !$meta_id = absint( $meta_id ) )
+		return false;
+
+	if ( ! $table = _get_meta_table($meta_type) )
+		return false;
+
+	$id_column = ( 'user' == $meta_type ) ? 'umeta_id' : 'meta_id';
+
+	$meta = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $table WHERE $id_column = %d", $meta_id ) );
+
+	if ( empty( $meta ) )
+		return false;
+
+	if ( isset( $meta->meta_value ) )
+		$meta->meta_value = maybe_unserialize( $meta->meta_value );
+
+	return $meta;
+}
+
+/**
+ * Update meta data by meta ID
+ *
+ * @since 3.3.0
+ *
+ * @uses get_metadata_by_mid() Calls get_metadata_by_mid() to fetch the meta key, value
+ *		and object_id of the given meta_id.
+ *
+ * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
+ * @param int $meta_id ID for a specific meta row
+ * @param string $meta_value Metadata value
+ * @param string $meta_key Optional, you can provide a meta key to update it
+ * @return bool True on successful update, false on failure.
+ */
+function update_metadata_by_mid( $meta_type, $meta_id, $meta_value, $meta_key = false ) {
+	global $wpdb;
+
+	// Make sure everything is valid.
+	if ( ! $meta_type )
+		return false;
+
+	if ( ! $meta_id = absint( $meta_id ) )
+		return false;
+
+	if ( ! $table = _get_meta_table( $meta_type ) )
+		return false;
+
+	$column = esc_sql($meta_type . '_id');
+	$id_column = 'user' == $meta_type ? 'umeta_id' : 'meta_id';
+
+	// Fetch the meta and go on if it's found.
+	if ( $meta = get_metadata_by_mid( $meta_type, $meta_id ) ) {
+		$original_key = $meta->meta_key;
+		$original_value = $meta->meta_value;
+		$object_id = $meta->{$column};
+
+		// If a new meta_key (last parameter) was specified, change the meta key,
+		// otherwise use the original key in the update statement.
+		if ( false === $meta_key ) {
+			$meta_key = $original_key;
+		} elseif ( ! is_string( $meta_key ) ) {
+			return false;
+		}
+
+		// Sanitize the meta
+		$_meta_value = $meta_value;
+		$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type );
+		$meta_value = maybe_serialize( $meta_value );
+
+		// Format the data query arguments.
+		$data = array(
+			'meta_key' => $meta_key,
+			'meta_value' => $meta_value
+		);
+
+		// Format the where query arguments.
+		$where = array();
+		$where[$id_column] = $meta_id;
+
+		do_action( "update_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
+
+		if ( 'post' == $meta_type )
+			do_action( 'update_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
+
+		// Run the update query, all fields in $data are %s, $where is a %d.
+		$result = (bool) $wpdb->update( $table, $data, $where, '%s', '%d' );
+
+		// Clear the caches.
+		wp_cache_delete($object_id, $meta_type . '_meta');
+
+		do_action( "updated_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
+
+		if ( 'post' == $meta_type )
+			do_action( 'updated_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
+
+		return $result;
+	}
+
+	// And if the meta was not found.
+	return false;
+}
+
+/**
+ * Delete meta data by meta ID
+ *
+ * @since 3.3.0
+ *
+ * @uses get_metadata_by_mid() Calls get_metadata_by_mid() to fetch the meta key, value
+ *		and object_id of the given meta_id.
+ *
+ * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
+ * @param int $meta_id ID for a specific meta row
+ * @return bool True on successful delete, false on failure.
+ */
+function delete_metadata_by_mid( $meta_type, $meta_id ) {
+	global $wpdb;
+
+	// Make sure everything is valid.
+	if ( ! $meta_type )
+		return false;
+
+	if ( ! $meta_id = absint( $meta_id ) )
+		return false;
+
+	if ( ! $table = _get_meta_table( $meta_type ) )
+		return false;
+
+	// object and id columns
+	$column = esc_sql($meta_type . '_id');
+	$id_column = 'user' == $meta_type ? 'umeta_id' : 'meta_id';
+
+	// Fetch the meta and go on if it's found.
+	if ( $meta = get_metadata_by_mid( $meta_type, $meta_id ) ) {
+		$object_id = $meta->{$column};
+
+		do_action( "delete_{$meta_type}_meta", (array) $meta_id, $object_id, $meta->meta_key, $meta->meta_value );
+
+		// Old-style action.
+		if ( 'post' == $meta_type || 'comment' == $meta_type )
+			do_action( "delete_{$meta_type}meta", $meta_id );
+
+		// Run the query, will return true if deleted, false otherwise
+		$result = (bool) $wpdb->delete( $table, array( $id_column => $meta_id ) );
+
+		// Clear the caches.
+		wp_cache_delete($object_id, $meta_type . '_meta');
+
+		do_action( "deleted_{$meta_type}_meta", (array) $meta_id, $object_id, $meta->meta_key, $meta->meta_value );
+
+		// Old-style action.
+		if ( 'post' == $meta_type || 'comment' == $meta_type )
+			do_action( "deleted_{$meta_type}meta", $meta_id );
+
+		return $result;
+
+	}
+
+	// Meta id was not found.
+	return false;
+}
+
+/**
+ * Update the metadata cache for the specified objects.
+ *
+ * @since 2.9.0
+ * @uses $wpdb WordPress database object for queries.
+ *
+ * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
+ * @param int|array $object_ids array or comma delimited list of object IDs to update cache for
+ * @return mixed Metadata cache for the specified objects, or false on failure.
+ */
 function update_meta_cache($meta_type, $object_ids) {
 	if ( empty( $meta_type ) || empty( $object_ids ) )
 		return false;
@@ -170,17 +541,20 @@
 
 	$cache_key = $meta_type . '_meta';
 	$ids = array();
+	$cache = array();
 	foreach ( $object_ids as $id ) {
-		if ( false === wp_cache_get($id, $cache_key) )
+		$cached_object = wp_cache_get( $id, $cache_key );
+		if ( false === $cached_object )
 			$ids[] = $id;
+		else
+			$cache[$id] = $cached_object;
 	}
 
 	if ( empty( $ids ) )
-		return false;
+		return $cache;
 
 	// Get meta info
 	$id_list = join(',', $ids);
-	$cache = array();
 	$meta_list = $wpdb->get_results( $wpdb->prepare("SELECT $column, meta_key, meta_value FROM $table WHERE $column IN ($id_list)",
 		$meta_type), ARRAY_A );
 
@@ -204,14 +578,229 @@
 	foreach ( $ids as $id ) {
 		if ( ! isset($cache[$id]) )
 			$cache[$id] = array();
+		wp_cache_add( $id, $cache[$id], $cache_key );
 	}
 
-	foreach ( array_keys($cache) as $object)
-		wp_cache_set($object, $cache[$object], $cache_key);
-
 	return $cache;
 }
 
+/**
+ * Given a meta query, generates SQL clauses to be appended to a main query
+ *
+ * @since 3.2.0
+ *
+ * @see WP_Meta_Query
+ *
+ * @param array $meta_query A meta query
+ * @param string $type Type of meta
+ * @param string $primary_table
+ * @param string $primary_id_column
+ * @param object $context (optional) The main query object
+ * @return array( 'join' => $join_sql, 'where' => $where_sql )
+ */
+function get_meta_sql( $meta_query, $type, $primary_table, $primary_id_column, $context = null ) {
+	$meta_query_obj = new WP_Meta_Query( $meta_query );
+	return $meta_query_obj->get_sql( $type, $primary_table, $primary_id_column, $context );
+}
+
+/**
+ * Container class for a multiple metadata query
+ *
+ * @since 3.2.0
+ */
+class WP_Meta_Query {
+	/**
+	* List of metadata queries. A single query is an associative array:
+	* - 'key' string The meta key
+	* - 'value' string|array The meta value
+	* - 'compare' (optional) string How to compare the key to the value.
+	*              Possible values: '=', '!=', '>', '>=', '<', '<=', 'LIKE', 'NOT LIKE', 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN'.
+	*              Default: '='
+	* - 'type' string (optional) The type of the value.
+	*              Possible values: 'NUMERIC', 'BINARY', 'CHAR', 'DATE', 'DATETIME', 'DECIMAL', 'SIGNED', 'TIME', 'UNSIGNED'.
+	*              Default: 'CHAR'
+	*
+	* @since 3.2.0
+	* @access public
+	* @var array
+	*/
+	public $queries = array();
+
+	/**
+	 * The relation between the queries. Can be one of 'AND' or 'OR'.
+	 *
+	 * @since 3.2.0
+	 * @access public
+	 * @var string
+	 */
+	public $relation;
+
+	/**
+	 * Constructor
+	 *
+	 * @param array $meta_query (optional) A meta query
+	 */
+	function __construct( $meta_query = false ) {
+		if ( !$meta_query )
+			return;
+
+		if ( isset( $meta_query['relation'] ) && strtoupper( $meta_query['relation'] ) == 'OR' ) {
+			$this->relation = 'OR';
+		} else {
+			$this->relation = 'AND';
+		}
+
+		$this->queries = array();
+
+		foreach ( $meta_query as $key => $query ) {
+			if ( ! is_array( $query ) )
+				continue;
+
+			$this->queries[] = $query;
+		}
+	}
+
+	/**
+	 * Constructs a meta query based on 'meta_*' query vars
+	 *
+	 * @since 3.2.0
+	 * @access public
+	 *
+	 * @param array $qv The query variables
+	 */
+	function parse_query_vars( $qv ) {
+		$meta_query = array();
+
+		// Simple query needs to be first for orderby=meta_value to work correctly
+		foreach ( array( 'key', 'compare', 'type' ) as $key ) {
+			if ( !empty( $qv[ "meta_$key" ] ) )
+				$meta_query[0][ $key ] = $qv[ "meta_$key" ];
+		}
+
+		// WP_Query sets 'meta_value' = '' by default
+		if ( isset( $qv[ 'meta_value' ] ) && '' !== $qv[ 'meta_value' ] )
+			$meta_query[0]['value'] = $qv[ 'meta_value' ];
+
+		if ( !empty( $qv['meta_query'] ) && is_array( $qv['meta_query'] ) ) {
+			$meta_query = array_merge( $meta_query, $qv['meta_query'] );
+		}
+
+		$this->__construct( $meta_query );
+	}
+
+	/**
+	 * Generates SQL clauses to be appended to a main query.
+	 *
+	 * @since 3.2.0
+	 * @access public
+	 *
+	 * @param string $type Type of meta
+	 * @param string $primary_table
+	 * @param string $primary_id_column
+	 * @param object $context (optional) The main query object
+	 * @return array( 'join' => $join_sql, 'where' => $where_sql )
+	 */
+	function get_sql( $type, $primary_table, $primary_id_column, $context = null ) {
+		global $wpdb;
+
+		if ( ! $meta_table = _get_meta_table( $type ) )
+			return false;
+
+		$meta_id_column = esc_sql( $type . '_id' );
+
+		$join = array();
+		$where = array();
+
+		foreach ( $this->queries as $k => $q ) {
+			$meta_key = isset( $q['key'] ) ? trim( $q['key'] ) : '';
+			$meta_type = isset( $q['type'] ) ? strtoupper( $q['type'] ) : 'CHAR';
+
+			if ( 'NUMERIC' == $meta_type )
+				$meta_type = 'SIGNED';
+			elseif ( ! in_array( $meta_type, array( 'BINARY', 'CHAR', 'DATE', 'DATETIME', 'DECIMAL', 'SIGNED', 'TIME', 'UNSIGNED' ) ) )
+				$meta_type = 'CHAR';
+
+			$i = count( $join );
+			$alias = $i ? 'mt' . $i : $meta_table;
+
+			// Set JOIN
+			$join[$i]  = "INNER JOIN $meta_table";
+			$join[$i] .= $i ? " AS $alias" : '';
+			$join[$i] .= " ON ($primary_table.$primary_id_column = $alias.$meta_id_column)";
+
+			$where[$k] = '';
+			if ( !empty( $meta_key ) )
+				$where[$k] = $wpdb->prepare( "$alias.meta_key = %s", $meta_key );
+
+			if ( !isset( $q['value'] ) ) {
+				if ( empty( $where[$k] ) )
+					unset( $join[$i] );
+				continue;
+			}
+
+			$meta_value = $q['value'];
+
+			$meta_compare = is_array( $meta_value ) ? 'IN' : '=';
+			if ( isset( $q['compare'] ) )
+				$meta_compare = strtoupper( $q['compare'] );
+
+			if ( ! in_array( $meta_compare, array( '=', '!=', '>', '>=', '<', '<=', 'LIKE', 'NOT LIKE', 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN' ) ) )
+				$meta_compare = '=';
+
+			if ( in_array( $meta_compare, array( 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN' ) ) ) {
+				if ( ! is_array( $meta_value ) )
+					$meta_value = preg_split( '/[,\s]+/', $meta_value );
+
+				if ( empty( $meta_value ) ) {
+					unset( $join[$i] );
+					continue;
+				}
+			} else {
+				$meta_value = trim( $meta_value );
+			}
+
+			if ( 'IN' == substr( $meta_compare, -2) ) {
+				$meta_compare_string = '(' . substr( str_repeat( ',%s', count( $meta_value ) ), 1 ) . ')';
+			} elseif ( 'BETWEEN' == substr( $meta_compare, -7) ) {
+				$meta_value = array_slice( $meta_value, 0, 2 );
+				$meta_compare_string = '%s AND %s';
+			} elseif ( 'LIKE' == substr( $meta_compare, -4 ) ) {
+				$meta_value = '%' . like_escape( $meta_value ) . '%';
+				$meta_compare_string = '%s';
+			} else {
+				$meta_compare_string = '%s';
+			}
+
+			if ( ! empty( $where[$k] ) )
+				$where[$k] .= ' AND ';
+
+			$where[$k] = ' (' . $where[$k] . $wpdb->prepare( "CAST($alias.meta_value AS {$meta_type}) {$meta_compare} {$meta_compare_string})", $meta_value );
+		}
+
+		$where = array_filter( $where );
+
+		if ( empty( $where ) )
+			$where = '';
+		else
+			$where = ' AND (' . implode( "\n{$this->relation} ", $where ) . ' )';
+
+		$join = implode( "\n", $join );
+		if ( ! empty( $join ) )
+			$join = ' ' . $join;
+
+		return apply_filters_ref_array( 'get_meta_sql', array( compact( 'join', 'where' ), $this->queries, $type, $primary_table, $primary_id_column, $context ) );
+	}
+}
+
+/**
+ * Retrieve the name of the metadata table for the specified object type.
+ *
+ * @since 2.9.0
+ * @uses $wpdb WordPress database object for queries.
+ *
+ * @param string $type Type of object to get metadata table for (e.g., comment, post, or user)
+ * @return mixed Metadata table name, or false if no metadata table exists
+ */
 function _get_meta_table($type) {
 	global $wpdb;
 
@@ -222,4 +811,57 @@
 
 	return $wpdb->$table_name;
 }
-?>
+
+/**
+ * Determine whether a meta key is protected
+ *
+ * @since 3.1.3
+ *
+ * @param string $meta_key Meta key
+ * @return bool True if the key is protected, false otherwise.
+ */
+function is_protected_meta( $meta_key, $meta_type = null ) {
+	$protected = ( '_' == $meta_key[0] );
+
+	return apply_filters( 'is_protected_meta', $protected, $meta_key, $meta_type );
+}
+
+/**
+ * Sanitize meta value
+ *
+ * @since 3.1.3
+ *
+ * @param string $meta_key Meta key
+ * @param mixed $meta_value Meta value to sanitize
+ * @param string $meta_type Type of meta
+ * @return mixed Sanitized $meta_value
+ */
+function sanitize_meta( $meta_key, $meta_value, $meta_type ) {
+	return apply_filters( "sanitize_{$meta_type}_meta_{$meta_key}", $meta_value, $meta_key, $meta_type );
+}
+
+/**
+ * Register meta key
+ *
+ * @since 3.3.0
+ *
+ * @param string $meta_type Type of meta
+ * @param string $meta_key Meta key
+ * @param string|array $sanitize_callback A function or method to call when sanitizing the value of $meta_key.
+ * @param string|array $auth_callback Optional. A function or method to call when performing edit_post_meta, add_post_meta, and delete_post_meta capability checks.
+ * @param array $args Arguments
+ */
+function register_meta( $meta_type, $meta_key, $sanitize_callback, $auth_callback = null ) {
+	if ( is_callable( $sanitize_callback ) )
+		add_filter( "sanitize_{$meta_type}_meta_{$meta_key}", $sanitize_callback, 10, 3 );
+
+	if ( empty( $auth_callback ) ) {
+		if ( is_protected_meta( $meta_key, $meta_type ) )
+			$auth_callback = '__return_false';
+		else
+			$auth_callback = '__return_true';
+	}
+
+	if ( is_callable( $auth_callback ) )
+		add_filter( "auth_{$meta_type}_meta_{$meta_key}", $auth_callback, 10, 6 );
+}