Ticket #30681: meta.php.diff

wp-includes/meta.php

@@ -1420 +1420 @@
                                         break;
 
                                 default :
-                                        $where = $wpdb->prepare( '%s', $meta_value );
+                                        $where = '';
+                                        if ( '' !== $meta_value ) {
+                                                $where = $wpdb->prepare( '%s', $meta_value );
+                                        }
                                         break;
 
                         }