public function deleteOembedCaches( $post_id = 0 ) {
		if ( $post_id ) {
			global $wp_embed;
			$wp_embed->delete_oembed_caches( $post_id );
		} else {
			global $wpdb;
			$post_metas = $wpdb->get_results( "SELECT post_id, meta_key FROM {$wpdb->postmeta} WHERE meta_key LIKE '_oembed_%' " );
			foreach ( $post_metas as $post_meta ) {
				delete_post_meta( $post_meta->post_id, $post_meta->meta_key );
			}
		}
	}