Hey dear lists,
Here is a self contained example showing strange behavior from a real life example concerning the use of postgis_topology topogeometry type.
The problem is :
when trying to return setof topogeometry,
the "return query" gives an error of type where there is none, and the return next is working fine.
The precise error message is ERROR 42804
"ERROR: structure of query does not match function result type
DETAIL: Returned type ttt.fake_topogeometry does not match expected type integer in column 1.
CONTEXT: PL/pgSQL function ttt.testtopogeom(ttt.fake_topogeometry) line 9 at RETURN QUERY
Is it ok, postres bug, postgis bug?
What are the possible corrections?
Here is the self contained code stored in the "ttt" schema.
DROP SCHEMA IF EXISTS ttt CASCADE;
DROP TYPE IF EXISTS ttt.fake_topogeometry CASCADE;
CREATE TYPE ttt.fake_topogeometry AS
DROP FUNCTION IF EXISTS ttt.testTopogeom(test_topom ttt.fake_topogeometry);
CREATE FUNCTION ttt.testTopogeom(test_topom ttt.fake_topogeometry)
RETURNS SETOF ttt.fake_topogeometry AS
-- this function is an empty function to test return of multiple topogeom
the_topo ttt.fake_topogeometry;
RETURN NEXT (1,1,1,1)::ttt.fake_topogeometry;
--RETURN NEXT (3,3,3,3)::ttt.fake_topogeometry;
RETURN QUERY SELECT (1,1,1,1)::ttt.fake_topogeometry as foo;
--SELECT (3,3,3,3)::ttt.fake_topogeometry as foo
LANGUAGE plpgsql IMMUTABLE;
FROM ttt.testTopogeom((2,2,2,2)::ttt.fake_topogeometry);