There are many different ways.
The easiest is to use snapshot transaction (which is default).
Since snapshot provides consistent view of whole database,
it can't see changes that happened after its start,
thus in this transaction you can't update such records.

Ivan

----- Original Message -----
From: "Constantijn Wolfs cw.s" <cw.s@...>
To: <firebird-support@yahoogroups.com>
Sent: Thursday, June 17, 2004 3:46 PM
Subject: [firebird-support] How to detect a record changed between read and update?


> Hello,
>
> I want to raise an exception when a record changed between the original
> read and the update with a sp.
>
> I could do a select on the old values and proceed with the update when
> the record was found. But is there a better way to do this, making the
> change of overwriting other updates as small as possible, without locking?
>
> Constantijn