diff --git a/qrcode/lib/MysqliDb/MysqliDb.php b/qrcode/lib/MysqliDb/MysqliDb.php
index 176d089..d44dca7 100644
--- a/qrcode/lib/MysqliDb/MysqliDb.php
+++ b/qrcode/lib/MysqliDb/MysqliDb.php
@@ -1845,7 +1845,7 @@ class MysqliDb
         $dataColumns = array_keys($tableData);
         if ($isInsert) {
             if (isset ($dataColumns[0]))
-                $this->_query .= ' (`' . implode($dataColumns, '`, `') . '`) ';
+                $this->_query .= ' (`' . implode('`, `', $dataColumns) . '`) ';
             $this->_query .= ' VALUES (';
         } else {
             $this->_query .= " SET ";
@@ -2513,4 +2513,4 @@ class MysqliDb
     }
 }
 
-// END class
\ No newline at end of file
+// END class