Changeset 53065

Timestamp:

04/05/2022 01:53:59 AM (4 years ago)

Author:

peterwilsoncc

Message:

Query: Cache comments feeds in WP_Query.

Cache queries to the comments table in WP_Query for various comments feeds. Only comment IDs are stored for each feeds cache to avoid doubling up caching with each individual comment's cache.

Props spacedmonkey, boonebgorges, pbearne.
Fixes #36904.

File:

• trunk/src/wp-includes/class-wp-query.php (modified) (2 diffs)

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

@@ -2721 +2721 @@
                         $climits  = ( ! empty( $climits ) ) ? $climits : '';
 
-                        $comments = (array) $wpdb->get_results( "SELECT $distinct {$wpdb->comments}.* FROM {$wpdb->comments} $cjoin $cwhere $cgroupby $corderby $climits" );
+                        $comments_request = "SELECT $distinct {$wpdb->comments}.comment_ID FROM {$wpdb->comments} $cjoin $cwhere $cgroupby $corderby $climits";
+
+                        $key          = md5( $comments_request );
+                        $last_changed = wp_cache_get_last_changed( 'comment' ) . ':' . wp_cache_get_last_changed( 'posts' );
+
+                        $cache_key   = "comment_feed:$key:$last_changed";
+                        $comment_ids = wp_cache_get( $cache_key, 'comment' );
+                        if ( false === $comment_ids ) {
+                                $comment_ids = $wpdb->get_col( $comments_request );
+                                wp_cache_add( $cache_key, $comment_ids, 'comment' );
+                        }
+                        _prime_comment_caches( $comment_ids, false );
+
                         // Convert to WP_Comment.
                         /** @var WP_Comment[] */
-                        $this->comments      = array_map( 'get_comment', $comments );
+                        $this->comments      = array_map( 'get_comment', $comment_ids );
                         $this->comment_count = count( $this->comments );
 
@@ -3165 +3177 @@
                         $climits = apply_filters_ref_array( 'comment_feed_limits', array( 'LIMIT ' . get_option( 'posts_per_rss' ), &$this ) );
 
-                        $comments_request = "SELECT {$wpdb->comments}.* FROM {$wpdb->comments} $cjoin $cwhere $cgroupby $corderby $climits";
-                        $comments         = $wpdb->get_results( $comments_request );
+                        $comments_request = "SELECT {$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' );
+                        if ( false === $comment_ids ) {
+                                $comment_ids = $wpdb->get_col( $comments_request );
+                                wp_cache_add( $cache_key, $comment_ids, 'comment' );
+                        }
+                        _prime_comment_caches( $comment_ids, false );
+
                         // Convert to WP_Comment.
                         /** @var WP_Comment[] */
-                        $this->comments      = array_map( 'get_comment', $comments );
+                        $this->comments      = array_map( 'get_comment', $comment_ids );
                         $this->comment_count = count( $this->comments );
                 }