Re: Can I use a query with UPDATE on its SET?

Hi Ho!

--- On Thu, 2/26/09, Craig Ringer <craig(at)postnewspapers(dot)com(dot)au> wrote:

> Eus wrote:
> > Hi Ho!
> >
> > Since I can do:
> >
> > INSERT INTO table (SELECT a_transaction.*);
> >
> > I am wondering whether I can do:
> >
> > UPDATE table SET (SELECT a_transaction.*) WHERE
> primary_key = (SELECT a_transaction.primary_key);
>
> UPDATE table SET fieldname = (SELECT ..) WHERE primary_key
> = (SELECT...)

Is it possible to eliminate the use of `fieldname' completely?
So, I just need to type `UPDATE table SET (SELECT ...) WHERE primary_key'.

I think this should be possible because if the subquery in the SET clause returns the same number of columns with the same types of those of the destination table, PostgreSQL should be able to just update the values at once.

Thanks.

> --
> Craig Ringer

Best regards,
Eus (FSF member #4445)

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