Ticket #5137: intersection.diff

wp-includes/query.php

@@ -1064 +1064 @@
                 }
 
                 if ( !empty($q['tag_slug__and']) ) {
-                        $count = 0;
-                        foreach ( $q['tag_slug__and'] as $tag_and ) {
-                                $join .= " LEFT JOIN $wpdb->term_relationships AS tr$count ON ($wpdb->posts.ID = tr$count.object_id) LEFT JOIN $wpdb->term_taxonomy AS tt$count ON (tr$count.term_taxonomy_id = tt$count.term_taxonomy_id) LEFT JOIN $wpdb->terms AS term$count ON (tt$count.term_id = term$count.term_id) ";
-                                $whichcat .= " AND term$count.slug = '$tag_and' ";
-                                $count++;
-                        }
+                        $tsql = "SELECT p.ID FROM $wpdb->posts p LEFT JOIN $wpdb->term_relationships tr ON (p.ID = tr.object_id) LEFT JOIN $wpdb->term_taxonomy tt ON (tr.term_taxonomy_id = tt.term_taxonomy_id) LEFT JOIN $wpdb->terms t ON (tt.term_id = t.term_id)";
+                        $tsql .= "WHERE tt.taxonomy = 'post_tag' AND t.slug IN ('" . implode("', '", $q['tag_slug__and']) . "')";
+                        $tsql .= "GROUP BY p.ID HAVING count(p.ID) = " . count($q['tag_slug__and']);
+                        $post_ids = $wpdb->get_col($tsql);
+                        
+                        if ( count($post_ids) )
+                                $where .= "AND $wpdb->posts.ID IN (" . implode(', ', $post_ids) . ") ";
+                        else
+                                $where = "AND 0 = 1";
+
                         $reqtag = is_term( $q['tag_slug__and'][0], 'post_tag' );
                         if ( !empty($reqtag) )
                                 $q['tag_id'] = $reqtag['term_id'];