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/htdocs/wp-includes/meta.php

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PHP | 906 lines | 459 code | 179 blank | 268 comment | 143 complexity | 44a8f6f570f15681b6dd968f16fee83f MD5 | raw file
  1<?php
  2/**
  3 * Metadata API
  4 *
  5 * Functions for retrieving and manipulating metadata of various WordPress object types. Metadata
  6 * for an object is a represented by a simple key-value pair. Objects may contain multiple
  7 * metadata entries that share the same key and differ only in their value.
  8 *
  9 * @package WordPress
 10 * @subpackage Meta
 11 * @since 2.9.0
 12 */
 13
 14/**
 15 * Add metadata for the specified object.
 16 *
 17 * @since 2.9.0
 18 * @uses $wpdb WordPress database object for queries.
 19 * @uses do_action() Calls 'added_{$meta_type}_meta' with meta_id of added metadata entry,
 20 * 		object ID, meta key, and meta value
 21 *
 22 * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
 23 * @param int $object_id ID of the object metadata is for
 24 * @param string $meta_key Metadata key
 25 * @param string $meta_value Metadata value
 26 * @param bool $unique Optional, default is false. Whether the specified metadata key should be
 27 * 		unique for the object. If true, and the object already has a value for the specified
 28 * 		metadata key, no change will be made
 29 * @return bool The meta ID on successful update, false on failure.
 30 */
 31function add_metadata($meta_type, $object_id, $meta_key, $meta_value, $unique = false) {
 32	if ( !$meta_type || !$meta_key )
 33		return false;
 34
 35	if ( !$object_id = absint($object_id) )
 36		return false;
 37
 38	if ( ! $table = _get_meta_table($meta_type) )
 39		return false;
 40
 41	global $wpdb;
 42
 43	$column = esc_sql($meta_type . '_id');
 44
 45	// expected_slashed ($meta_key)
 46	$meta_key = stripslashes($meta_key);
 47	$meta_value = stripslashes_deep($meta_value);
 48	$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type );
 49
 50	$check = apply_filters( "add_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $unique );
 51	if ( null !== $check )
 52		return $check;
 53
 54	if ( $unique && $wpdb->get_var( $wpdb->prepare(
 55		"SELECT COUNT(*) FROM $table WHERE meta_key = %s AND $column = %d",
 56		$meta_key, $object_id ) ) )
 57		return false;
 58
 59	$_meta_value = $meta_value;
 60	$meta_value = maybe_serialize( $meta_value );
 61
 62	do_action( "add_{$meta_type}_meta", $object_id, $meta_key, $_meta_value );
 63
 64	$result = $wpdb->insert( $table, array(
 65		$column => $object_id,
 66		'meta_key' => $meta_key,
 67		'meta_value' => $meta_value
 68	) );
 69
 70	if ( ! $result )
 71		return false;
 72
 73	$mid = (int) $wpdb->insert_id;
 74
 75	wp_cache_delete($object_id, $meta_type . '_meta');
 76
 77	do_action( "added_{$meta_type}_meta", $mid, $object_id, $meta_key, $_meta_value );
 78
 79	return $mid;
 80}
 81
 82/**
 83 * Update metadata for the specified object. If no value already exists for the specified object
 84 * ID and metadata key, the metadata will be added.
 85 *
 86 * @since 2.9.0
 87 * @uses $wpdb WordPress database object for queries.
 88 * @uses do_action() Calls 'update_{$meta_type}_meta' before updating metadata with meta_id of
 89 * 		metadata entry to update, object ID, meta key, and meta value
 90 * @uses do_action() Calls 'updated_{$meta_type}_meta' after updating metadata with meta_id of
 91 * 		updated metadata entry, object ID, meta key, and meta value
 92 *
 93 * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
 94 * @param int $object_id ID of the object metadata is for
 95 * @param string $meta_key Metadata key
 96 * @param string $meta_value Metadata value
 97 * @param string $prev_value Optional. If specified, only update existing metadata entries with
 98 * 		the specified value. Otherwise, update all entries.
 99 * @return bool True on successful update, false on failure.
100 */
101function update_metadata($meta_type, $object_id, $meta_key, $meta_value, $prev_value = '') {
102	if ( !$meta_type || !$meta_key )
103		return false;
104
105	if ( !$object_id = absint($object_id) )
106		return false;
107
108	if ( ! $table = _get_meta_table($meta_type) )
109		return false;
110
111	global $wpdb;
112
113	$column = esc_sql($meta_type . '_id');
114	$id_column = 'user' == $meta_type ? 'umeta_id' : 'meta_id';
115
116	// expected_slashed ($meta_key)
117	$meta_key = stripslashes($meta_key);
118	$passed_value = $meta_value;
119	$meta_value = stripslashes_deep($meta_value);
120	$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type );
121
122	$check = apply_filters( "update_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $prev_value );
123	if ( null !== $check )
124		return (bool) $check;
125
126	// Compare existing value to new value if no prev value given and the key exists only once.
127	if ( empty($prev_value) ) {
128		$old_value = get_metadata($meta_type, $object_id, $meta_key);
129		if ( count($old_value) == 1 ) {
130			if ( $old_value[0] === $meta_value )
131				return false;
132		}
133	}
134
135	if ( ! $meta_id = $wpdb->get_var( $wpdb->prepare( "SELECT $id_column FROM $table WHERE meta_key = %s AND $column = %d", $meta_key, $object_id ) ) )
136		return add_metadata($meta_type, $object_id, $meta_key, $passed_value);
137
138	$_meta_value = $meta_value;
139	$meta_value = maybe_serialize( $meta_value );
140
141	$data  = compact( 'meta_value' );
142	$where = array( $column => $object_id, 'meta_key' => $meta_key );
143
144	if ( !empty( $prev_value ) ) {
145		$prev_value = maybe_serialize($prev_value);
146		$where['meta_value'] = $prev_value;
147	}
148
149	do_action( "update_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
150
151	if ( 'post' == $meta_type )
152		do_action( 'update_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
153
154	$wpdb->update( $table, $data, $where );
155
156	wp_cache_delete($object_id, $meta_type . '_meta');
157
158	do_action( "updated_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
159
160	if ( 'post' == $meta_type )
161		do_action( 'updated_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
162
163	return true;
164}
165
166/**
167 * Delete metadata for the specified object.
168 *
169 * @since 2.9.0
170 * @uses $wpdb WordPress database object for queries.
171 * @uses do_action() Calls 'deleted_{$meta_type}_meta' after deleting with meta_id of
172 * 		deleted metadata entries, object ID, meta key, and meta value
173 *
174 * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
175 * @param int $object_id ID of the object metadata is for
176 * @param string $meta_key Metadata key
177 * @param string $meta_value Optional. Metadata value. If specified, only delete metadata entries
178 * 		with this value. Otherwise, delete all entries with the specified meta_key.
179 * @param bool $delete_all Optional, default is false. If true, delete matching metadata entries
180 * 		for all objects, ignoring the specified object_id. Otherwise, only delete matching
181 * 		metadata entries for the specified object_id.
182 * @return bool True on successful delete, false on failure.
183 */
184function delete_metadata($meta_type, $object_id, $meta_key, $meta_value = '', $delete_all = false) {
185	if ( !$meta_type || !$meta_key )
186		return false;
187
188	if ( (!$object_id = absint($object_id)) && !$delete_all )
189		return false;
190
191	if ( ! $table = _get_meta_table($meta_type) )
192		return false;
193
194	global $wpdb;
195
196	$type_column = esc_sql($meta_type . '_id');
197	$id_column = 'user' == $meta_type ? 'umeta_id' : 'meta_id';
198	// expected_slashed ($meta_key)
199	$meta_key = stripslashes($meta_key);
200	$meta_value = stripslashes_deep($meta_value);
201
202	$check = apply_filters( "delete_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $delete_all );
203	if ( null !== $check )
204		return (bool) $check;
205
206	$_meta_value = $meta_value;
207	$meta_value = maybe_serialize( $meta_value );
208
209	$query = $wpdb->prepare( "SELECT $id_column FROM $table WHERE meta_key = %s", $meta_key );
210
211	if ( !$delete_all )
212		$query .= $wpdb->prepare(" AND $type_column = %d", $object_id );
213
214	if ( $meta_value )
215		$query .= $wpdb->prepare(" AND meta_value = %s", $meta_value );
216
217	$meta_ids = $wpdb->get_col( $query );
218	if ( !count( $meta_ids ) )
219		return false;
220
221	if ( $delete_all )
222		$object_ids = $wpdb->get_col( $wpdb->prepare( "SELECT $type_column FROM $table WHERE meta_key = %s", $meta_key ) );
223
224	do_action( "delete_{$meta_type}_meta", $meta_ids, $object_id, $meta_key, $_meta_value );
225
226	// Old-style action.
227	if ( 'post' == $meta_type )
228		do_action( 'delete_postmeta', $meta_ids );
229
230	$query = "DELETE FROM $table WHERE $id_column IN( " . implode( ',', $meta_ids ) . " )";
231
232	$count = $wpdb->query($query);
233
234	if ( !$count )
235		return false;
236
237	if ( $delete_all ) {
238		foreach ( (array) $object_ids as $o_id ) {
239			wp_cache_delete($o_id, $meta_type . '_meta');
240		}
241	} else {
242		wp_cache_delete($object_id, $meta_type . '_meta');
243	}
244
245	do_action( "deleted_{$meta_type}_meta", $meta_ids, $object_id, $meta_key, $_meta_value );
246
247	// Old-style action.
248	if ( 'post' == $meta_type )
249		do_action( 'deleted_postmeta', $meta_ids );
250
251	return true;
252}
253
254/**
255 * Retrieve metadata for the specified object.
256 *
257 * @since 2.9.0
258 *
259 * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
260 * @param int $object_id ID of the object metadata is for
261 * @param string $meta_key Optional. Metadata key. If not specified, retrieve all metadata for
262 * 		the specified object.
263 * @param bool $single Optional, default is false. If true, return only the first value of the
264 * 		specified meta_key. This parameter has no effect if meta_key is not specified.
265 * @return string|array Single metadata value, or array of values
266 */
267function get_metadata($meta_type, $object_id, $meta_key = '', $single = false) {
268	if ( !$meta_type )
269		return false;
270
271	if ( !$object_id = absint($object_id) )
272		return false;
273
274	$check = apply_filters( "get_{$meta_type}_metadata", null, $object_id, $meta_key, $single );
275	if ( null !== $check ) {
276		if ( $single && is_array( $check ) )
277			return $check[0];
278		else
279			return $check;
280	}
281
282	$meta_cache = wp_cache_get($object_id, $meta_type . '_meta');
283
284	if ( !$meta_cache ) {
285		$meta_cache = update_meta_cache( $meta_type, array( $object_id ) );
286		$meta_cache = $meta_cache[$object_id];
287	}
288
289	if ( !$meta_key )
290		return $meta_cache;
291
292	if ( isset($meta_cache[$meta_key]) ) {
293		if ( $single )
294			return maybe_unserialize( $meta_cache[$meta_key][0] );
295		else
296			return array_map('maybe_unserialize', $meta_cache[$meta_key]);
297	}
298
299	if ($single)
300		return '';
301	else
302		return array();
303}
304
305/**
306 * Determine if a meta key is set for a given object
307 *
308 * @since 3.3.0
309 *
310 * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
311 * @param int $object_id ID of the object metadata is for
312 * @param string $meta_key Metadata key.
313 * @return boolean true of the key is set, false if not.
314 */
315function metadata_exists( $meta_type, $object_id, $meta_key ) {
316	if ( ! $meta_type )
317		return false;
318
319	if ( ! $object_id = absint( $object_id ) )
320		return false;
321
322	$check = apply_filters( "get_{$meta_type}_metadata", null, $object_id, $meta_key, true );
323	if ( null !== $check )
324		return true;
325
326	$meta_cache = wp_cache_get( $object_id, $meta_type . '_meta' );
327
328	if ( !$meta_cache ) {
329		$meta_cache = update_meta_cache( $meta_type, array( $object_id ) );
330		$meta_cache = $meta_cache[$object_id];
331	}
332
333	if ( isset( $meta_cache[ $meta_key ] ) )
334		return true;
335
336	return false;
337}
338
339/**
340 * Get meta data by meta ID
341 *
342 * @since 3.3.0
343 *
344 * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
345 * @param int $meta_id ID for a specific meta row
346 * @return object Meta object or false.
347 */
348function get_metadata_by_mid( $meta_type, $meta_id ) {
349	global $wpdb;
350
351	if ( ! $meta_type )
352		return false;
353
354	if ( !$meta_id = absint( $meta_id ) )
355		return false;
356
357	if ( ! $table = _get_meta_table($meta_type) )
358		return false;
359
360	$id_column = ( 'user' == $meta_type ) ? 'umeta_id' : 'meta_id';
361
362	$meta = $wpdb->get_row( $wpdb->prepare( "SELECT * FROM $table WHERE $id_column = %d", $meta_id ) );
363
364	if ( empty( $meta ) )
365		return false;
366
367	if ( isset( $meta->meta_value ) )
368		$meta->meta_value = maybe_unserialize( $meta->meta_value );
369
370	return $meta;
371}
372
373/**
374 * Update meta data by meta ID
375 *
376 * @since 3.3.0
377 *
378 * @uses get_metadata_by_mid() Calls get_metadata_by_mid() to fetch the meta key, value
379 *		and object_id of the given meta_id.
380 *
381 * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
382 * @param int $meta_id ID for a specific meta row
383 * @param string $meta_value Metadata value
384 * @param string $meta_key Optional, you can provide a meta key to update it
385 * @return bool True on successful update, false on failure.
386 */
387function update_metadata_by_mid( $meta_type, $meta_id, $meta_value, $meta_key = false ) {
388	global $wpdb;
389
390	// Make sure everything is valid.
391	if ( ! $meta_type )
392		return false;
393
394	if ( ! $meta_id = absint( $meta_id ) )
395		return false;
396
397	if ( ! $table = _get_meta_table( $meta_type ) )
398		return false;
399
400	$column = esc_sql($meta_type . '_id');
401	$id_column = 'user' == $meta_type ? 'umeta_id' : 'meta_id';
402
403	// Fetch the meta and go on if it's found.
404	if ( $meta = get_metadata_by_mid( $meta_type, $meta_id ) ) {
405		$original_key = $meta->meta_key;
406		$original_value = $meta->meta_value;
407		$object_id = $meta->{$column};
408
409		// If a new meta_key (last parameter) was specified, change the meta key,
410		// otherwise use the original key in the update statement.
411		if ( false === $meta_key ) {
412			$meta_key = $original_key;
413		} elseif ( ! is_string( $meta_key ) ) {
414			return false;
415		}
416
417		// Sanitize the meta
418		$_meta_value = $meta_value;
419		$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type );
420		$meta_value = maybe_serialize( $meta_value );
421
422		// Format the data query arguments.
423		$data = array(
424			'meta_key' => $meta_key,
425			'meta_value' => $meta_value
426		);
427
428		// Format the where query arguments.
429		$where = array();
430		$where[$id_column] = $meta_id;
431
432		do_action( "update_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
433
434		if ( 'post' == $meta_type )
435			do_action( 'update_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
436
437		// Run the update query, all fields in $data are %s, $where is a %d.
438		$result = (bool) $wpdb->update( $table, $data, $where, '%s', '%d' );
439
440		// Clear the caches.
441		wp_cache_delete($object_id, $meta_type . '_meta');
442
443		do_action( "updated_{$meta_type}_meta", $meta_id, $object_id, $meta_key, $_meta_value );
444
445		if ( 'post' == $meta_type )
446			do_action( 'updated_postmeta', $meta_id, $object_id, $meta_key, $meta_value );
447
448		return $result;
449	}
450
451	// And if the meta was not found.
452	return false;
453}
454
455/**
456 * Delete meta data by meta ID
457 *
458 * @since 3.3.0
459 *
460 * @uses get_metadata_by_mid() Calls get_metadata_by_mid() to fetch the meta key, value
461 *		and object_id of the given meta_id.
462 *
463 * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
464 * @param int $meta_id ID for a specific meta row
465 * @return bool True on successful delete, false on failure.
466 */
467function delete_metadata_by_mid( $meta_type, $meta_id ) {
468	global $wpdb;
469
470	// Make sure everything is valid.
471	if ( ! $meta_type )
472		return false;
473
474	if ( ! $meta_id = absint( $meta_id ) )
475		return false;
476
477	if ( ! $table = _get_meta_table( $meta_type ) )
478		return false;
479
480	// object and id columns
481	$column = esc_sql($meta_type . '_id');
482	$id_column = 'user' == $meta_type ? 'umeta_id' : 'meta_id';
483
484	// Fetch the meta and go on if it's found.
485	if ( $meta = get_metadata_by_mid( $meta_type, $meta_id ) ) {
486		$object_id = $meta->{$column};
487
488		do_action( "delete_{$meta_type}_meta", (array) $meta_id, $object_id, $meta->meta_key, $meta->meta_value );
489
490		// Old-style action.
491		if ( 'post' == $meta_type || 'comment' == $meta_type )
492			do_action( "delete_{$meta_type}meta", $meta_id );
493
494		// Run the query, will return true if deleted, false otherwise
495		$result = (bool) $wpdb->delete( $table, array( $id_column => $meta_id ) );
496
497		// Clear the caches.
498		wp_cache_delete($object_id, $meta_type . '_meta');
499
500		do_action( "deleted_{$meta_type}_meta", (array) $meta_id, $object_id, $meta->meta_key, $meta->meta_value );
501
502		// Old-style action.
503		if ( 'post' == $meta_type || 'comment' == $meta_type )
504			do_action( "deleted_{$meta_type}meta", $meta_id );
505
506		return $result;
507
508	}
509
510	// Meta id was not found.
511	return false;
512}
513
514/**
515 * Update the metadata cache for the specified objects.
516 *
517 * @since 2.9.0
518 * @uses $wpdb WordPress database object for queries.
519 *
520 * @param string $meta_type Type of object metadata is for (e.g., comment, post, or user)
521 * @param int|array $object_ids array or comma delimited list of object IDs to update cache for
522 * @return mixed Metadata cache for the specified objects, or false on failure.
523 */
524function update_meta_cache($meta_type, $object_ids) {
525	if ( empty( $meta_type ) || empty( $object_ids ) )
526		return false;
527
528	if ( ! $table = _get_meta_table($meta_type) )
529		return false;
530
531	$column = esc_sql($meta_type . '_id');
532
533	global $wpdb;
534
535	if ( !is_array($object_ids) ) {
536		$object_ids = preg_replace('|[^0-9,]|', '', $object_ids);
537		$object_ids = explode(',', $object_ids);
538	}
539
540	$object_ids = array_map('intval', $object_ids);
541
542	$cache_key = $meta_type . '_meta';
543	$ids = array();
544	$cache = array();
545	foreach ( $object_ids as $id ) {
546		$cached_object = wp_cache_get( $id, $cache_key );
547		if ( false === $cached_object )
548			$ids[] = $id;
549		else
550			$cache[$id] = $cached_object;
551	}
552
553	if ( empty( $ids ) )
554		return $cache;
555
556	// Get meta info
557	$id_list = join(',', $ids);
558	$meta_list = $wpdb->get_results( $wpdb->prepare("SELECT $column, meta_key, meta_value FROM $table WHERE $column IN ($id_list)",
559		$meta_type), ARRAY_A );
560
561	if ( !empty($meta_list) ) {
562		foreach ( $meta_list as $metarow) {
563			$mpid = intval($metarow[$column]);
564			$mkey = $metarow['meta_key'];
565			$mval = $metarow['meta_value'];
566
567			// Force subkeys to be array type:
568			if ( !isset($cache[$mpid]) || !is_array($cache[$mpid]) )
569				$cache[$mpid] = array();
570			if ( !isset($cache[$mpid][$mkey]) || !is_array($cache[$mpid][$mkey]) )
571				$cache[$mpid][$mkey] = array();
572
573			// Add a value to the current pid/key:
574			$cache[$mpid][$mkey][] = $mval;
575		}
576	}
577
578	foreach ( $ids as $id ) {
579		if ( ! isset($cache[$id]) )
580			$cache[$id] = array();
581		wp_cache_add( $id, $cache[$id], $cache_key );
582	}
583
584	return $cache;
585}
586
587/**
588 * Given a meta query, generates SQL clauses to be appended to a main query
589 *
590 * @since 3.2.0
591 *
592 * @see WP_Meta_Query
593 *
594 * @param array $meta_query A meta query
595 * @param string $type Type of meta
596 * @param string $primary_table
597 * @param string $primary_id_column
598 * @param object $context (optional) The main query object
599 * @return array( 'join' => $join_sql, 'where' => $where_sql )
600 */
601function get_meta_sql( $meta_query, $type, $primary_table, $primary_id_column, $context = null ) {
602	$meta_query_obj = new WP_Meta_Query( $meta_query );
603	return $meta_query_obj->get_sql( $type, $primary_table, $primary_id_column, $context );
604}
605
606/**
607 * Container class for a multiple metadata query
608 *
609 * @since 3.2.0
610 */
611class WP_Meta_Query {
612	/**
613	* List of metadata queries. A single query is an associative array:
614	* - 'key' string The meta key
615	* - 'value' string|array The meta value
616	* - 'compare' (optional) string How to compare the key to the value.
617	*              Possible values: '=', '!=', '>', '>=', '<', '<=', 'LIKE', 'NOT LIKE', 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN'.
618	*              Default: '='
619	* - 'type' string (optional) The type of the value.
620	*              Possible values: 'NUMERIC', 'BINARY', 'CHAR', 'DATE', 'DATETIME', 'DECIMAL', 'SIGNED', 'TIME', 'UNSIGNED'.
621	*              Default: 'CHAR'
622	*
623	* @since 3.2.0
624	* @access public
625	* @var array
626	*/
627	public $queries = array();
628
629	/**
630	 * The relation between the queries. Can be one of 'AND' or 'OR'.
631	 *
632	 * @since 3.2.0
633	 * @access public
634	 * @var string
635	 */
636	public $relation;
637
638	/**
639	 * Constructor
640	 *
641	 * @param array $meta_query (optional) A meta query
642	 */
643	function __construct( $meta_query = false ) {
644		if ( !$meta_query )
645			return;
646
647		if ( isset( $meta_query['relation'] ) && strtoupper( $meta_query['relation'] ) == 'OR' ) {
648			$this->relation = 'OR';
649		} else {
650			$this->relation = 'AND';
651		}
652
653		$this->queries = array();
654
655		foreach ( $meta_query as $key => $query ) {
656			if ( ! is_array( $query ) )
657				continue;
658
659			$this->queries[] = $query;
660		}
661	}
662
663	/**
664	 * Constructs a meta query based on 'meta_*' query vars
665	 *
666	 * @since 3.2.0
667	 * @access public
668	 *
669	 * @param array $qv The query variables
670	 */
671	function parse_query_vars( $qv ) {
672		$meta_query = array();
673
674		// Simple query needs to be first for orderby=meta_value to work correctly
675		foreach ( array( 'key', 'compare', 'type' ) as $key ) {
676			if ( !empty( $qv[ "meta_$key" ] ) )
677				$meta_query[0][ $key ] = $qv[ "meta_$key" ];
678		}
679
680		// WP_Query sets 'meta_value' = '' by default
681		if ( isset( $qv[ 'meta_value' ] ) && '' !== $qv[ 'meta_value' ] )
682			$meta_query[0]['value'] = $qv[ 'meta_value' ];
683
684		if ( !empty( $qv['meta_query'] ) && is_array( $qv['meta_query'] ) ) {
685			$meta_query = array_merge( $meta_query, $qv['meta_query'] );
686		}
687
688		$this->__construct( $meta_query );
689	}
690
691	/**
692	 * Generates SQL clauses to be appended to a main query.
693	 *
694	 * @since 3.2.0
695	 * @access public
696	 *
697	 * @param string $type Type of meta
698	 * @param string $primary_table
699	 * @param string $primary_id_column
700	 * @param object $context (optional) The main query object
701	 * @return array( 'join' => $join_sql, 'where' => $where_sql )
702	 */
703	function get_sql( $type, $primary_table, $primary_id_column, $context = null ) {
704		global $wpdb;
705
706		if ( ! $meta_table = _get_meta_table( $type ) )
707			return false;
708
709		$meta_id_column = esc_sql( $type . '_id' );
710
711		$join = array();
712		$where = array();
713
714		$key_only_queries = array();
715		$queries = array();
716
717		// Split out the meta_key only queries (we can only do this for OR)
718		if ( 'OR' == $this->relation ) {
719			foreach ( $this->queries as $k => $q ) {
720				if ( ! isset( $q['value'] ) && ! empty( $q['key'] ) )
721					$key_only_queries[$k] = $q;
722				else
723					$queries[$k] = $q;
724			}
725		} else {
726			$queries = $this->queries;
727		}
728
729		// Specify all the meta_key only queries in one go
730		if ( $key_only_queries ) {
731			$join[]  = "INNER JOIN $meta_table ON $primary_table.$primary_id_column = $meta_table.$meta_id_column";
732
733			foreach ( $key_only_queries as $key => $q )
734				$where["key-only-$key"] = $wpdb->prepare( "$meta_table.meta_key = %s", trim( $q['key'] ) );
735		}
736
737		foreach ( $queries as $k => $q ) {
738			$meta_key = isset( $q['key'] ) ? trim( $q['key'] ) : '';
739			$meta_type = isset( $q['type'] ) ? strtoupper( $q['type'] ) : 'CHAR';
740
741			if ( 'NUMERIC' == $meta_type )
742				$meta_type = 'SIGNED';
743			elseif ( ! in_array( $meta_type, array( 'BINARY', 'CHAR', 'DATE', 'DATETIME', 'DECIMAL', 'SIGNED', 'TIME', 'UNSIGNED' ) ) )
744				$meta_type = 'CHAR';
745
746			$meta_value = isset( $q['value'] ) ? $q['value'] : null;
747
748			if ( isset( $q['compare'] ) )
749				$meta_compare = strtoupper( $q['compare'] );
750			else
751				$meta_compare = is_array( $meta_value ) ? 'IN' : '=';
752
753			if ( ! in_array( $meta_compare, array(
754				'=', '!=', '>', '>=', '<', '<=',
755				'LIKE', 'NOT LIKE',
756				'IN', 'NOT IN',
757				'BETWEEN', 'NOT BETWEEN',
758				'NOT EXISTS'
759			) ) )
760				$meta_compare = '=';
761
762			$i = count( $join );
763			$alias = $i ? 'mt' . $i : $meta_table;
764
765			if ( 'NOT EXISTS' == $meta_compare ) {
766				$join[$i]  = "LEFT JOIN $meta_table";
767				$join[$i] .= $i ? " AS $alias" : '';
768				$join[$i] .= " ON ($primary_table.$primary_id_column = $alias.$meta_id_column AND $alias.meta_key = '$meta_key')";
769
770				$where[$k] = ' ' . $alias . '.' . $meta_id_column . ' IS NULL';
771
772				continue;
773			}
774
775			$join[$i]  = "INNER JOIN $meta_table";
776			$join[$i] .= $i ? " AS $alias" : '';
777			$join[$i] .= " ON ($primary_table.$primary_id_column = $alias.$meta_id_column)";
778
779			$where[$k] = '';
780			if ( !empty( $meta_key ) )
781				$where[$k] = $wpdb->prepare( "$alias.meta_key = %s", $meta_key );
782
783			if ( is_null( $meta_value ) ) {
784				if ( empty( $where[$k] ) )
785					unset( $join[$i] );
786				continue;
787			}
788
789			if ( in_array( $meta_compare, array( 'IN', 'NOT IN', 'BETWEEN', 'NOT BETWEEN' ) ) ) {
790				if ( ! is_array( $meta_value ) )
791					$meta_value = preg_split( '/[,\s]+/', $meta_value );
792
793				if ( empty( $meta_value ) ) {
794					unset( $join[$i] );
795					continue;
796				}
797			} else {
798				$meta_value = trim( $meta_value );
799			}
800
801			if ( 'IN' == substr( $meta_compare, -2) ) {
802				$meta_compare_string = '(' . substr( str_repeat( ',%s', count( $meta_value ) ), 1 ) . ')';
803			} elseif ( 'BETWEEN' == substr( $meta_compare, -7) ) {
804				$meta_value = array_slice( $meta_value, 0, 2 );
805				$meta_compare_string = '%s AND %s';
806			} elseif ( 'LIKE' == substr( $meta_compare, -4 ) ) {
807				$meta_value = '%' . like_escape( $meta_value ) . '%';
808				$meta_compare_string = '%s';
809			} else {
810				$meta_compare_string = '%s';
811			}
812
813			if ( ! empty( $where[$k] ) )
814				$where[$k] .= ' AND ';
815
816			$where[$k] = ' (' . $where[$k] . $wpdb->prepare( "CAST($alias.meta_value AS {$meta_type}) {$meta_compare} {$meta_compare_string})", $meta_value );
817		}
818
819		$where = array_filter( $where );
820
821		if ( empty( $where ) )
822			$where = '';
823		else
824			$where = ' AND (' . implode( "\n{$this->relation} ", $where ) . ' )';
825
826		$join = implode( "\n", $join );
827		if ( ! empty( $join ) )
828			$join = ' ' . $join;
829
830		return apply_filters_ref_array( 'get_meta_sql', array( compact( 'join', 'where' ), $this->queries, $type, $primary_table, $primary_id_column, $context ) );
831	}
832}
833
834/**
835 * Retrieve the name of the metadata table for the specified object type.
836 *
837 * @since 2.9.0
838 * @uses $wpdb WordPress database object for queries.
839 *
840 * @param string $type Type of object to get metadata table for (e.g., comment, post, or user)
841 * @return mixed Metadata table name, or false if no metadata table exists
842 */
843function _get_meta_table($type) {
844	global $wpdb;
845
846	$table_name = $type . 'meta';
847
848	if ( empty($wpdb->$table_name) )
849		return false;
850
851	return $wpdb->$table_name;
852}
853
854/**
855 * Determine whether a meta key is protected
856 *
857 * @since 3.1.3
858 *
859 * @param string $meta_key Meta key
860 * @return bool True if the key is protected, false otherwise.
861 */
862function is_protected_meta( $meta_key, $meta_type = null ) {
863	$protected = ( '_' == $meta_key[0] );
864
865	return apply_filters( 'is_protected_meta', $protected, $meta_key, $meta_type );
866}
867
868/**
869 * Sanitize meta value
870 *
871 * @since 3.1.3
872 *
873 * @param string $meta_key Meta key
874 * @param mixed $meta_value Meta value to sanitize
875 * @param string $meta_type Type of meta
876 * @return mixed Sanitized $meta_value
877 */
878function sanitize_meta( $meta_key, $meta_value, $meta_type ) {
879	return apply_filters( "sanitize_{$meta_type}_meta_{$meta_key}", $meta_value, $meta_key, $meta_type );
880}
881
882/**
883 * Register meta key
884 *
885 * @since 3.3.0
886 *
887 * @param string $meta_type Type of meta
888 * @param string $meta_key Meta key
889 * @param string|array $sanitize_callback A function or method to call when sanitizing the value of $meta_key.
890 * @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.
891 * @param array $args Arguments
892 */
893function register_meta( $meta_type, $meta_key, $sanitize_callback, $auth_callback = null ) {
894	if ( is_callable( $sanitize_callback ) )
895		add_filter( "sanitize_{$meta_type}_meta_{$meta_key}", $sanitize_callback, 10, 3 );
896
897	if ( empty( $auth_callback ) ) {
898		if ( is_protected_meta( $meta_key, $meta_type ) )
899			$auth_callback = '__return_false';
900		else
901			$auth_callback = '__return_true';
902	}
903
904	if ( is_callable( $auth_callback ) )
905		add_filter( "auth_{$meta_type}_meta_{$meta_key}", $auth_callback, 10, 6 );
906}