Well this looks so silly, but it is not, because this is not happening in Saas version and i just want to confirm whether it is bug or not...

 Consider an example,

In Account.Invoice (Standard) - "partner_id" is set as required=True, which will in turn set Not Null Constraint in the Backend..

Lets say in my custom module, am going to override the column "partner_id" to set required=False, Now am in for surprise, my  property is not considered at all...

Did anyone faced this weird problem in Saas version, If so did you find any fix for this...

And am pretty sure this is bug left behind in Saas version..