Ühel kenal päeval, R, 2007-03-02 kell 10:13, kirjutas Tom Lane:
> Andrew Dunstan <andrew@dunslane.net> writes:
> > My instinct would be to follow your first strategy, i.e. detect which
> > path is needed rather than try one and then if it fails do the other.
>
> The very first thing you need to think about is how to solve the race
> condition problem, ie, two backends concurrently trying to insert
> identical data.
Then one of them will update the data inserted by whoeved got the insert
first.
> Until you have a plausible mechanism for that, the
> whole thing is pie-in-the-sky.
Is'nt the standard way of doing it thus:
UPDATE
IF NOT FOUND THEN INSERT IF DUPLICATE KEY THEN UPDATE END IF
END IF
At least this is how UPSERT is usually done in plpgsql
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