Changeset 56513

Timestamp:

09/05/2023 12:21:27 PM (13 months ago)

Author:

spacedmonkey

Message:

Query: Use split queries in WP_Query if persistent object caching is enabled.

Prior to this commit, the WP_Query class split the query for posts into two database queries. First, it initiated an ID-based query to retrieve post IDs, followed by a call to _prime_post_caches to fetch post objects if they weren't already in memory. This splitting of queries was limited to cases where fewer than 500 posts were being requested, to prevent a potentially large database query within the IN statement in _prime_post_caches.

However, this limitation becomes unnecessary when a persistent object cache is enabled, as the post objects can be efficiently retrieved from the fast object cache. This commit transfers the responsibility of fetching posts to the object cache, which not only speeds up the process but also reduces the strain on the database server.

Props peterwilsoncc, spacedmonkey, SergeyBiryukov.
Fixes #57296.

Location:

trunk

Files:

• src/wp-includes/class-wp-query.php (modified) (1 diff)
• tests/phpunit/tests/post/nav-menu.php (modified) (2 diffs)
• tests/phpunit/tests/post/query.php (modified) (1 diff)

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

@@ -3272 +3272 @@
 
         if ( null === $this->posts ) {
-            $split_the_query = ( $old_request == $this->request && "{$wpdb->posts}.*" === $fields && ! empty( $limits ) && $q['posts_per_page'] < 500 );
+            $split_the_query = (
+                $old_request == $this->request
+                && "{$wpdb->posts}.*" === $fields
+                && (
+                    wp_using_ext_object_cache()
+                    || ( ! empty( $limits ) && $q['posts_per_page'] < 500 )
+                )
+            );
 
             /**

trunk/tests/phpunit/tests/post/nav-menu.php

@@ -343 +343 @@
 
         $start_num_queries = get_num_queries();
-        wp_get_nav_menu_items( $this->menu_id );
+        wp_get_nav_menu_items( $this->menu_id, array( 'nopaging' => false ) );
         $queries_made = get_num_queries() - $start_num_queries;
-        $this->assertSame( 6, $queries_made, 'Only does 6 database queries when running wp_get_nav_menu_items.' );
+        $this->assertSame( 7, $queries_made, 'Only does 7 database queries when running wp_get_nav_menu_items.' );
 
         $args = $action->get_args();
         $this->assertSameSets( $menu_nav_ids, $args[0][1], '_prime_post_caches() was not executed.' );
-        $this->assertSameSets( $post_ids, $args[1][1], '_prime_post_caches() was not executed.' );
+        $this->assertSameSets( $post_ids, $args[2][1], '_prime_post_caches() was not executed.' );
     }
 
@@ -384 +384 @@
 
         $start_num_queries = get_num_queries();
-        wp_get_nav_menu_items( $this->menu_id );
+        wp_get_nav_menu_items( $this->menu_id, array( 'nopaging' => false ) );
         get_term_meta( $term_ids[0] );
         $queries_made = get_num_queries() - $start_num_queries;
-        $this->assertSame( 6, $queries_made, 'Only does 6 database queries when running wp_get_nav_menu_items.' );
+        $this->assertSame( 7, $queries_made, 'Only does 7 database queries when running wp_get_nav_menu_items.' );
 
         $args       = $action_terms->get_args();

trunk/tests/phpunit/tests/post/query.php

@@ -776 +776 @@
         $this->assertIsInt( $q->found_posts );
     }
+
+    /**
+     * @ticket 57296
+     * @covers WP_Query::get_posts
+     */
+    public function test_split_the_query_object_cache() {
+        $filter = new MockAction();
+        add_filter( 'split_the_query', array( $filter, 'filter' ) );
+
+        $q = new WP_Query(
+            array(
+                'posts_per_page' => 501,
+            )
+        );
+
+        $this->assertSame( (bool) wp_using_ext_object_cache(), $filter->get_args()[0][0] );
+    }
 }