Subject Re: foreign Key Deletion
Author davidrevill69
In you original example, the banks record cannot be deleted if a
customer is using it and one cannot be added or updated without a
bank record existing.

However you will have add the constraint 'not null' on IdBank in
customers to prevent a record being posted with a null value

--- In, "Maurizio P."
<mauriz_po@...> wrote:
> Thanks for Answers
> now i know more about foreign keys ,
> i have a question refering to the two tables of my previous message
(tBanks , tCustomers) :
> i want the user cannot delete a tBanks record if it exists in the
tCustomers table .
> No other constraints , e.g. a tCustomer record can be not
connected to any tBanks record .
> ...using foreign keys , i can't leave a tCustomer record without a
tBanks record connected .
> can i do that only with triggers ?
> thanks
> Maurizio
> [Non-text portions of this message have been removed]