INSERT before UPDATE?

am Thu, dem 16.08.2007, um 10:30:01 +0200 mailte Ji?� N?mec folgendes:

Hello,

I would like to ask you for an advice.

There are two tables in my PostgreSQL database - main table with datas and
second with translations for all languages of these records.

When I try to UPDATE a record in the language table and this record
doesn't exists there I need to INSERT into the language table (from
default language version) and execute UPDATE statement again.

Could you tell me if is this possible and if so - how to do it?

Okay, i try to ask our doc-bot on IRC:

11:15 < akretschmer> ??upsert
11:15 < rtfm_please> For information about upsert
11:15 < rtfm_please> see http://www.postgresql.org/docs/current/static/plpgsql-control-structures.html#PLPGSQL-UPSERT-EXAMPLE

Andreas
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Andreas Kretschmer
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am Thu, dem 16.08.2007, um 14:11:07 +0200 mailte Ji??� N??mec folgendes:

see
http://www.postgresql.org/docs/current/static/plpgsql-control-structures.html#PLPGSQL-UPSERT-EXAMPLE

Yes I see, but I'll try to describe it in more detail:

I could write plpgsql trigger function which will UPDATE a record (or
INSERT new record) when the record is not found. But as far as I know
a trigger is not executed when a updated record is not found, so this
solution doesn't work for me. I don't want to change my application -
I would like to set this behaviour directly in PostgreSQL database so
I couldn't use a method from your example (...which requires that all
SQL UPDATE statements need to be modified).

Maybe you can achieve this with a RULE.
I'm not sure, but i would try ist.

Andreas
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Andreas Kretschmer
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