Ticket #22213: 22213.patch

wp-includes/query.php

@@ -2661 +2661 @@
 
                         $this->request = apply_filters( 'posts_request_ids', $this->request, $this );
 
-                        $ids = $wpdb->get_col( $this->request );
+                        if ( empty( $distinct ) )
+                                $ids = $wpdb->get_col( $this->request );
+                        else
+                                $ids = wp_list_pluck( $wpdb->get_results( $this->request ), 'ID' );
 
                         if ( $ids ) {
                                 $this->posts = $ids;