Yassin,

>I have two business objects with a parent child relationship which binds to two different mmgridview, but somehow I get the following message
>
>"Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign-key constraints."

There are quite a number of problems that will cause this error to appear. Often it's because you have a constraint on a database table and the data that you are retrieving is invalid--incorrect maximum length, invalid key values, and so on. I recommend looking carefully at the data you are returning and examining your database constraints to see where the problem is.

Best Regards,