Re: function returning a row - Mailing list pgsql-novice

From Michael Fuhr
Subject Re: function returning a row
Date
Msg-id 20041118161911.GA44655@winnie.fuhr.org
Whole thread Raw
In response to function returning a row  (Kjetil Haaland <kjetil.haaland@student.uib.no>)
Responses Re: function returning a row  (Kjetil Haaland <kjetil.haaland@student.uib.no>)
List pgsql-novice
On Thu, Nov 18, 2004 at 02:54:31PM +0100, Kjetil Haaland wrote:
>
> I have made my own type alignres that holds a string and an integer. I have
> created the type in postgres and tried to insert into it and it works. I also
> have a function that returns a row (or composite type). I have used
>
> tupdesc = RelationNameGetTupleDesc("alignres");
>
> to set it to return my own type.  When i try to use the function in postgres
> it says
>
> ERROR:  relation "alignres" does not exist

The type you created isn't a composite -- it's a base (scalar) type.
Do you want to return a row with a field that has your type, or do
you just want to return a single value of your type?

> If i try to let the function use a type that is only created in postgres (not
> c code) then it works.

I assume you mean it works for a composite type like this:

CREATE TYPE foo AS (val INTEGER, fstring TEXT);

As the CREATE TYPE documentation says, this is essentially the same
as the row type of a table.  But your type is a scalar, not a composite,
so RelationNameGetTupleDesc() doesn't work.

> Is it possible to use my own type to be returned?

Yes, and you've already written a function that does: alignres_in().
Its CREATE FUNCTION statement says "RETURNS alignres", doesn't it?
If you want the new function to return a single value of your type,
then do what alignres_in() does.

--
Michael Fuhr
http://www.fuhr.org/~mfuhr/

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