Changeset 53941 for trunk/src/wp-includes/class-wp-query.php

Timestamp:

08/25/2022 04:21:40 AM (4 years ago)

Author:

peterwilsoncc

Message:

Query: Cache post ID database query within WP_Query.

Add object caching to the first database query in WP_Query, ie the database query for post IDs that match the desired result. Randomly ordered queries remain uncached as they are not intended to return consistent results.

Caching of ID queries is enabled by default, per the post object, term and meta caches.

Props spacedmonkey, aaroncampbell, batmoo, chriscct7, costdev, dd32, drewapicture, johnbillion, mukesh27, nacin, ocean90, peterwilsoncc, ryan, scribu, sergeybiryukov, tillkruss.
Fixes #22176.

File:

• trunk/src/wp-includes/class-wp-query.php (modified) (7 diffs)

trunk/src/wp-includes/class-wp-query.php

@@ -1875 +1875 @@
 
                 if ( ! isset( $q['cache_results'] ) ) {
-                        if ( wp_using_ext_object_cache() ) {
-                                $q['cache_results'] = false;
-                        } else {
-                                $q['cache_results'] = true;
-                        }
+                        $q['cache_results'] = true;
                 }
 
@@ -3073 +3069 @@
                 $this->posts = apply_filters_ref_array( 'posts_pre_query', array( null, &$this ) );
 
+                /*
+                 * Ensure the ID database query is able to be cached.
+                 *
+                 * Random queries are expected to have unpredictable results and
+                 * cannot be cached. Note the space before `RAND` in the string
+                 * search, that to ensure against a collision with another
+                 * function.
+                 */
+                $id_query_is_cacheable = ! str_contains( strtoupper( $orderby ), ' RAND(' );
+                if ( $q['cache_results'] && $id_query_is_cacheable ) {
+                        $cache_args = $q;
+
+                        unset(
+                                $cache_args['suppress_filters'],
+                                $cache_args['cache_results'],
+                                $cache_args['fields'],
+                                $cache_args['update_post_meta_cache'],
+                                $cache_args['update_post_term_cache'],
+                                $cache_args['lazy_load_term_meta'],
+                                $cache_args['update_menu_item_cache']
+                        );
+
+                        $new_request = str_replace( $fields, "{$wpdb->posts}.*", $this->request );
+                        $key         = md5( serialize( $cache_args ) . $new_request );
+
+                        $last_changed = wp_cache_get_last_changed( 'posts' );
+                        if ( ! empty( $this->tax_query->queried_terms ) ) {
+                                $last_changed .= wp_cache_get_last_changed( 'terms' );
+                        }
+
+                        $cache_key = "wp_query:$key:$last_changed";
+
+                        if ( null === $this->posts ) {
+                                $cached_results = wp_cache_get( $cache_key, 'posts' );
+
+                                if ( $cached_results ) {
+                                        if ( 'ids' === $q['fields'] ) {
+                                                /** @var int[] */
+                                                $this->posts = array_map( 'intval', $cached_results['posts'] );
+                                        } else {
+                                                _prime_post_caches( $cached_results['posts'], $q['update_post_term_cache'], $q['update_post_meta_cache'] );
+                                                /** @var WP_Post[] */
+                                                $this->posts = array_map( 'get_post', $cached_results['posts'] );
+                                        }
+
+                                        $this->post_count    = count( $this->posts );
+                                        $this->found_posts   = $cached_results['found_posts'];
+                                        $this->max_num_pages = $cached_results['max_num_pages'];
+
+                                        if ( 'ids' === $q['fields'] ) {
+                                                return $this->posts;
+                                        } elseif ( 'id=>parent' === $q['fields'] ) {
+                                                /** @var int[] */
+                                                $post_parents = array();
+
+                                                foreach ( $this->posts as $key => $post ) {
+                                                        $obj              = new stdClass();
+                                                        $obj->ID          = (int) $post->ID;
+                                                        $obj->post_parent = (int) $post->post_parent;
+
+                                                        $this->posts[ $key ] = $obj;
+
+                                                        $post_parents[ $obj->ID ] = $obj->post_parent;
+                                                }
+
+                                                return $post_parents;
+                                        }
+                                }
+                        }
+                }
+
                 if ( 'ids' === $q['fields'] ) {
                         if ( null === $this->posts ) {
@@ -3083 +3150 @@
                         $this->set_found_posts( $q, $limits );
 
+                        if ( $q['cache_results'] && $id_query_is_cacheable ) {
+                                $cache_value = array(
+                                        'posts'         => $this->posts,
+                                        'found_posts'   => $this->found_posts,
+                                        'max_num_pages' => $this->max_num_pages,
+                                );
+
+                                wp_cache_set( $cache_key, $cache_value, 'posts' );
+                        }
+
                         return $this->posts;
                 }
@@ -3095 +3172 @@
 
                         /** @var int[] */
-                        $r = array();
+                        $post_parents = array();
+                        $post_ids     = array();
+
                         foreach ( $this->posts as $key => $post ) {
                                 $this->posts[ $key ]->ID          = (int) $post->ID;
                                 $this->posts[ $key ]->post_parent = (int) $post->post_parent;
 
-                                $r[ (int) $post->ID ] = (int) $post->post_parent;
-                        }
-
-                        return $r;
+                                $post_parents[ (int) $post->ID ] = (int) $post->post_parent;
+                                $post_ids[]                      = (int) $post->ID;
+                        }
+
+                        if ( $q['cache_results'] && $id_query_is_cacheable ) {
+                                $cache_value = array(
+                                        'posts'         => $post_ids,
+                                        'found_posts'   => $this->found_posts,
+                                        'max_num_pages' => $this->max_num_pages,
+                                );
+
+                                wp_cache_set( $cache_key, $cache_value, 'posts' );
+                        }
+
+                        return $post_parents;
                 }
 
@@ -3145 +3235 @@
                                 $this->request = apply_filters( 'posts_request_ids', $this->request, $this );
 
-                                $ids = $wpdb->get_col( $this->request );
-
-                                if ( $ids ) {
-                                        $this->posts = $ids;
+                                $post_ids = $wpdb->get_col( $this->request );
+
+                                if ( $post_ids ) {
+                                        $this->posts = $post_ids;
                                         $this->set_found_posts( $q, $limits );
-                                        _prime_post_caches( $ids, $q['update_post_term_cache'], $q['update_post_meta_cache'] );
+                                        _prime_post_caches( $post_ids, $q['update_post_term_cache'], $q['update_post_meta_cache'] );
                                 } else {
                                         $this->posts = array();
@@ -3166 +3256 @@
                 }
 
+                if ( $q['cache_results'] && $id_query_is_cacheable ) {
+                        $post_ids = wp_list_pluck( $this->posts, 'ID' );
+
+                        $cache_value = array(
+                                'posts'         => $post_ids,
+                                'found_posts'   => $this->found_posts,
+                                'max_num_pages' => $this->max_num_pages,
+                        );
+
+                        wp_cache_set( $cache_key, $cache_value, 'posts' );
+                }
+
                 if ( ! empty( $this->posts ) && $q['update_menu_item_cache'] ) {
                         update_menu_item_cache( $this->posts );
@@ -3202 +3304 @@
                         $comments_request = "SELECT {$wpdb->comments}.comment_ID FROM {$wpdb->comments} $cjoin $cwhere $cgroupby $corderby $climits";
 
-                        $key          = md5( $comments_request );
-                        $last_changed = wp_cache_get_last_changed( 'comment' );
-
-                        $cache_key   = "comment_feed:$key:$last_changed";
-                        $comment_ids = wp_cache_get( $cache_key, 'comment' );
+                        $comment_key          = md5( $comments_request );
+                        $comment_last_changed = wp_cache_get_last_changed( 'comment' );
+
+                        $comment_cache_key = "comment_feed:$comment_key:$comment_last_changed";
+                        $comment_ids       = wp_cache_get( $comment_cache_key, 'comment' );
                         if ( false === $comment_ids ) {
                                 $comment_ids = $wpdb->get_col( $comments_request );
-                                wp_cache_add( $cache_key, $comment_ids, 'comment' );
+                                wp_cache_add( $comment_cache_key, $comment_ids, 'comment' );
                         }
                         _prime_comment_caches( $comment_ids, false );