diff --git a/fastphp/db/Sql.php b/fastphp/db/Sql.php
index 8245325..18da4ce 100644
--- a/fastphp/db/Sql.php
+++ b/fastphp/db/Sql.php
@@ -35,7 +35,7 @@ class Sql
                 $this->filter .= ' WHERE ';
             }
             if (is_string($where)) {
-                $this->filter .= ' WHERE ' . $where;
+                $this->filter .= $where;
             } else {
                 $flag = true;
                 foreach ($where as $key => $value) {