Re: Foreign Key Constraint Deletion Order - Mailing list pgsql-sql

On Mon, 19 Nov 2001 cnliou@eurosport.com wrote:

> Then I am in big big trouble! Please imagine a very
> usual scenario:
> [example snipped]

I think you can do this as part of a trigger on PurchaseMaster and
something that doesn't do the subtraction if the subselect returns
a NULL in the detail trigger (or subtracts 0), not as pretty, but
it should function.  The master trigger would subtract as necessary
for the details for the user.