WordPress Version: 5.9
/**
* Deletes metadata for the specified object.
*
* @since 2.9.0
*
* @global wpdb $wpdb WordPress database abstraction object.
*
* @param string $meta_type Type of object metadata is for. Accepts 'post', 'comment', 'term', 'user',
* or any other object type with an associated meta table.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $meta_value Optional. Metadata value. Must be serializable if non-scalar.
* If specified, only delete metadata entries with this value.
* Otherwise, delete all entries with the specified meta_key.
* Pass `null`, `false`, or an empty string to skip this check.
* (For backward compatibility, it is not possible to pass an empty string
* to delete those entries with an empty string for a value.)
* @param bool $delete_all Optional. If true, delete matching metadata entries for all objects,
* ignoring the specified object_id. Otherwise, only delete
* matching metadata entries for the specified object_id. Default false.
* @return bool True on successful delete, false on failure.
*/
function delete_metadata($meta_type, $object_id, $meta_key, $meta_value = '', $delete_all = false)
{
global $wpdb;
if (!$meta_type || !$meta_key || !is_numeric($object_id) && !$delete_all) {
return false;
}
$object_id = absint($object_id);
if (!$object_id && !$delete_all) {
return false;
}
$table = _get_meta_table($meta_type);
if (!$table) {
return false;
}
$type_column = sanitize_key($meta_type . '_id');
$id_column = ('user' === $meta_type) ? 'umeta_id' : 'meta_id';
// expected_slashed ($meta_key)
$meta_key = wp_unslash($meta_key);
$meta_value = wp_unslash($meta_value);
/**
* Short-circuits deleting metadata of a specific type.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
* Returning a non-null value will effectively short-circuit the function.
*
* Possible hook names include:
*
* - `delete_post_metadata`
* - `delete_comment_metadata`
* - `delete_term_metadata`
* - `delete_user_metadata`
*
* @since 3.1.0
*
* @param null|bool $delete Whether to allow metadata deletion of the given type.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $meta_value Metadata value. Must be serializable if non-scalar.
* @param bool $delete_all Whether to delete the matching metadata entries
* for all objects, ignoring the specified $object_id.
* Default false.
*/
$check = apply_filters("delete_{$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", $meta_key);
if (!$delete_all) {
$query .= $wpdb->prepare(" AND {$type_column} = %d", $object_id);
}
if ('' !== $meta_value && null !== $meta_value && false !== $meta_value) {
$query .= $wpdb->prepare(' AND meta_value = %s', $meta_value);
}
$meta_ids = $wpdb->get_col($query);
if (!count($meta_ids)) {
return false;
}
if ($delete_all) {
if ('' !== $meta_value && null !== $meta_value && false !== $meta_value) {
$object_ids = $wpdb->get_col($wpdb->prepare("SELECT {$type_column} FROM {$table} WHERE meta_key = %s AND meta_value = %s", $meta_key, $meta_value));
} else {
$object_ids = $wpdb->get_col($wpdb->prepare("SELECT {$type_column} FROM {$table} WHERE meta_key = %s", $meta_key));
}
}
/**
* Fires immediately before deleting metadata of a specific type.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
*
* Possible hook names include:
*
* - `delete_post_meta`
* - `delete_comment_meta`
* - `delete_term_meta`
* - `delete_user_meta`
*
* @since 3.1.0
*
* @param string[] $meta_ids An array of metadata entry IDs to delete.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $_meta_value Metadata value.
*/
do_action("delete_{$meta_type}_meta", $meta_ids, $object_id, $meta_key, $_meta_value);
// Old-style action.
if ('post' === $meta_type) {
/**
* Fires immediately before deleting metadata for a post.
*
* @since 2.9.0
*
* @param string[] $meta_ids An array of metadata entry IDs to delete.
*/
do_action('delete_postmeta', $meta_ids);
}
$query = "DELETE FROM {$table} WHERE {$id_column} IN( " . implode(',', $meta_ids) . ' )';
$count = $wpdb->query($query);
if (!$count) {
return false;
}
if ($delete_all) {
foreach ((array) $object_ids as $o_id) {
wp_cache_delete($o_id, $meta_type . '_meta');
}
} else {
wp_cache_delete($object_id, $meta_type . '_meta');
}
/**
* Fires immediately after deleting metadata of a specific type.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
*
* Possible hook names include:
*
* - `deleted_post_meta`
* - `deleted_comment_meta`
* - `deleted_term_meta`
* - `deleted_user_meta`
*
* @since 2.9.0
*
* @param string[] $meta_ids An array of metadata entry IDs to delete.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $_meta_value Metadata value.
*/
do_action("deleted_{$meta_type}_meta", $meta_ids, $object_id, $meta_key, $_meta_value);
// Old-style action.
if ('post' === $meta_type) {
/**
* Fires immediately after deleting metadata for a post.
*
* @since 2.9.0
*
* @param string[] $meta_ids An array of metadata entry IDs to delete.
*/
do_action('deleted_postmeta', $meta_ids);
}
return true;
}