Hi,

One word: TRIGGERS

More words: download the IB/FB documentation - see
http://www.ibphoenix.com/ibp_interbase_download.html#Docs


Martijn Tonies
InterBase Workbench - the developer tool for InterBase and Firebird
http://www.interbaseworkbench.com

Upscene Productions
http://www.upscene.com

"This is an object-oriented system.
If we change anything, the users object."

> Hi ,
>
> I am using Firebird , but just don't have a clue how to implement
> this one :
>
> Let's call table A (invoices) with fields : Invoice_ID integer ,
> invoice_sum numeric(16,3)
> Other fields are not important .
>
> Let's call table B ( payments ) with fields : payment__id integer,
> payment_sum numeric(16,3)
> Other fields are not important .
>
> Finaly , I need to have table C ( it's table where it can be seen what
> invoices is payment closing ( or partially closing )
>
> with fields : payment_id integer , invoice_id integer, closing_sum