I thought we had an example of this type of function in the docs, but we
don't. Here is one:
http://www.brasileiro.net:8080/postgres/cookbook/view-recipes.adp?section_id=535&format=long
---------------------------------------------------------------------------
Tom Lane wrote:
> "David Durst" <ddurst@larubber.com> writes:
> > CREATE FUNCTION lookup_account(varchar(32)) RETURNS SETOF accounts AS '
> > DECLARE
> > aname ALIAS FOR $1;
> > rec RECORD;
> > BEGIN
> > select into rec * from accounts where accountname = aname;
> > return rec;
> > END;'
> > LANGUAGE 'plpgsql';
>
> As written, this function can only return a single row (so you hardly
> need SETOF). If you intend that it be able to return multiple rows
> when accountname is not unique, then you'll need a loop and RETURN NEXT
> commands. It'd probably be less tedious to use a SQL-language function:
>
> CREATE FUNCTION lookup_account(varchar(32)) RETURNS SETOF accounts AS '
> select * from accounts where accountname = $1'
> language sql;
>
> > This seems to hang when I attempt to select it using:
>
> > select accountid(
> > lookup_account('some account')),
> > accountname(lookup_account('some account')),
> > type(lookup_account('some account')),
> > balance(lookup_account('some account'));
>
> It works for me (in 7.3), but in any case that's a bad approach: you're
> invoking the function four times, independently. Better is
>
> select accountid,accountname,type,balance
> from lookup_account('some account');
>
> (again, this syntax requires 7.3)
>
> regards, tom lane
>
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-- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610)
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