diff --git a/src/Model.php b/src/Model.php
index b010906..35a1c7f 100644
--- a/src/Model.php
+++ b/src/Model.php
@@ -139,6 +139,9 @@ class Model{
 
     protected static function convertField($data, $field){
         $options = static::getOptions($field);
+        if(is_null($data) && isset($options['not_null']) && $options['not_null'] == true)
+            throw new DatabaseException('Can\'t set null to NOT NULL field : '.$field);
+
         if(isset($options['type'])){
             switch(strtolower($options['type'])){
                 case 'int':
@@ -157,9 +160,6 @@ class Model{
             }
         }
 
-        if(is_null($data) && isset($options['not_null']) && $options['not_null'] == true)
-            throw new DatabaseException('Can\'t set null to NOT NULL field : '.$field);
-
         return $data;
     }