Updating an emty table?

Hi..

I have a small "problem" and I was wondering if you guys could give me a
recommendation. I have a table that initially is empty but the table is
always updated, so there is no insert first then update..
The table can hold 10-20 records for each order, and I was wondering how
to implement this update. There are two alternatives as far as I can
see..:

1. I can delete every row for the order on every update and do an insert
instead.

2. or I can write a function (stored proc) that first tries to update
and if update fails, it then does an insert.

The first one I know how to do (don't know how much penalty this would
cause?) and the second one is perhaps the best way to do it, but since I
have never written any stored proc for PostgreSQL yet, I need some
pointers on how to implement this...

Regards,

BTJ

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Bjørn T Johansen (BSc,MNIF)
Executive Manager
btj(at)havleik(dot)no Havleik Consulting
Phone : +47 67 54 15 17 Conradisvei 4
Fax : +47 67 54 13 91 N-1338 Sandvika
Cellular : +47 926 93 298 http://www.havleik.no
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