ERROR: type "foo_20110307_id_seq" already exists (expected relation "foo_20110307_id_seq" already exists)

Postgres 8.3.13

Hello,

I have a function to generate some tables with serial primary keys. (see
below).

Due to our multithreading, I can't avoid concurerent calls, so I just
catch the corresponding errors.

This works fine most of the time, but I sometimes get an error like in
$subject.

The issue is not about the table, but about the related sequence.

By trying to create a sequence that already exists, I'd expect an error
like

relation "foo_20110307_id_seq" already exists,

and not

type "foo_20110307_id_seq" already

I guess the latter matches the duplicate_object exception and I'll try
to catch it as well, but I wonder where this comes from.

Cheers,

Marc Mamin

CREATE OR REPLACE FUNCTION public.createtable_foo(varchar,INT)

RETURNS int4 AS

$BODY$

BEGIN

EXECUTE 'CREATE TABLE '||$1||'.foo_'||$2||

'( id serial NOT NULL,

foo varchar,

CONSTRAINT foo_'||$2||'_pk PRIMARY KEY (id)

)

';

--handle concurent calls

EXCEPTION WHEN duplicate_table THEN null;

END;

RETURN 0;

END;

$BODY$

LANGUAGE 'plpgsql' VOLATILE;