diff --git a/src/DB/Data/LocalTableData.php b/src/DB/Data/LocalTableData.php
index c834621..258d534 100644
--- a/src/DB/Data/LocalTableData.php
+++ b/src/DB/Data/LocalTableData.php
@@ -110,7 +110,7 @@ public function getChangeDiff($table, $key) {
 
         $wrapCast = function($arr, $p) {
             return array_map(function($el) use ($p) {
-                return "CAST(`{$p}`.`{$el}` AS CHAR CHARACTER SET utf8)";
+                return "COALESCE(CAST(`{$p}`.`{$el}` AS CHAR CHARACTER SET utf8), '')";
             }, $arr);
         };