Re: 9i Referential Integrity Locking

It depends on the front-end tools.

Some application generators (including Oracle*FORMS, up to 4.5, and then you have to set the switch) will perform an update by updating every single column on the table.

So you may not think you are updating the primary key, but the application code is doing it for you, and even a 'update with changing the value' causes the PK/FK lock to take place.

--
Jonathan Lewis
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Practical Oracle 8i: Building Efficient Databases


Paul Brewer wrote in message
<3cae1606_1_at_mk-nntp-1.news.uk.worldonline.com>...


>

>As ever, the advice from Thomas and Howard is excellent.

>Slight digression though:

>In a well designed system, how often does DML on primary keys occur?

>(Note: I'm *not* suggesting that it is unnecessary to index FK columns).

>