Re: Nested composite types again

On Nov 28, 2012, at 5:02 AM, Michael Kolomeitsev <mkolomeitsev(at)gmail(dot)com> wrote:

> Hi,
>
> I have already read this
> http://www.postgresql.org/docs/9.2/static/rowtypes.html#AEN7304
> but it didn't help.
>
> CREATE TABLE nodes (
> id SERIAL NOT NULL PRIMARY KEY,
> name TEXT NOT NULL
> );
>
> CREATE TYPE pathId AS (
> id INTEGER,
> node nodes
> );
>
> CREATE OR REPLACE FUNCTION test_AEN7304() RETURNS void AS $$
> DECLARE
> r pathId;
> n nodes;
> BEGIN
> n.name := 'abc';
> r.id := 1;
> r.node := n; -- All is ok
> -- r.node.name := 'def'; -- << Error here
> -- (r).node.name := 'def'; -- << and here
> ((r).node).name := 'def'; -- << and here
> END;
> $$ LANGUAGE 'plpgsql';
>
> And I can't even make 'n' as ALIAS FOR r.node (to simulate C-like pointer).
>
> What is the right syntax?
> Thanks

I have verified that plpgsql doesn't allow assignment like r.node.name='def' or (r).node.name or ((r).node).name

In Above case, you can use some variable like n and update the n composite variable and assigned it to r.node as you have already done in plpgsql.

Thanks & Regards,
Vibhor Kumar
EnterpriseDB Corporation
The Enterprise PostgreSQL Company
Blog:http://vibhork.blogspot.com