Ticket #36792: 36792.patch

src/wp-includes/query.php

@@ -3603 +3603 @@
                          * @param WP_Query $this    The WP_Query instance.
                          */
                         $this->request = apply_filters( 'posts_request_ids', $this->request, $this );
+                        
+                        if ( $q['cache_results'] ) {
+                                $key = md5( $this->request );
+                                $last_changed = wp_cache_get( 'last_changed', 'posts' );
+                                if ( ! $last_changed ) {
+                                        $last_changed = microtime();
+                                        wp_cache_set( 'last_changed', $last_changed, 'posts' );
+                                }
+                                $cache_key = "get_post_ids:$key:$last_changed";
+                                $ids = wp_cache_get( $cache_key, 'posts' );
+                                if ( false === $ids ) {
+                                        $ids = $wpdb->get_col( $this->request );
+                                        wp_cache_add( $cache_key, $ids, 'posts' );
+                                }
+                        } else {
+                                $ids = $wpdb->get_col( $this->request );
+                        }
 
-                        $ids = $wpdb->get_col( $this->request );
 
                         if ( $ids ) {
                                 $this->posts = $ids;