In a similar situation I am using a selectable stored procedure, which
calculates the current balance in an output variable.

Emil

--- In firebird-support@yahoogroups.com, "Sergio H. Gonzalez"
<shg_sistemas@...> wrote:

>
> Hi, I think this is a very old question, but I never did it with

Firebird

> before.
>
> I want to do a simpe current acount with in-out-balance columns. The

movements

> would come from the invoices and payments tables ordered by date. I

usually did

> it with triggers that insert the movements in a separate table and

re-calculate

> all the balances (with a stored procedure) for each record every

time something

> in inserted, modified or deleted. I wonder if there is a way to do

it "on the

> fly".. I mean when the user want to see some current account, just

do " select

> (some fields) from invoices union all select (some fields) from

payments order

> by 1" (being "1" the pos of the date field). Firts of all, I don't

know how fast

> would be this approach as the DB gets bigger, and second: I dont

know how to

> resolve the "balance" column on a select, because it depends on the

previous

> row. May I have some diferent opinions of experienced people?

Thanks!! -s

>