Intended behaviour of SET search_path with SQL functions?

=> SHOW search_path;
search_path
-------------
beta
(1 row)

=> CREATE OR REPLACE FUNCTION func_b() RETURNS SETOF int AS $$
SELECT id FROM table_a;
$$ LANGUAGE sql SET search_path = alpha;
ERROR: relation "table_a" does not exist
CONTEXT: SQL function "func_b"

=> \d table_a
Did not find any relation named "table_a".

=> \d alpha.table_a
Table "alpha.table_a"
Column | Type | Modifiers
--------+---------+-----------
id | integer |

If I temporarily create a beta.table_a then I get to create the function
and afterwards it does the right thing. It also works fine with a
pl/pgsql function - presumably it's all down to context on the initial
parse.

I can't think of a way to exploit this maliciously, or do anything other
than cause a little confusion, but I'm not sure it's intentional.

--
Richard Huxton
Archonet Ltd

Richard Huxton <dev(at)archonet(dot)com> writes:
> => CREATE OR REPLACE FUNCTION func_b() RETURNS SETOF int AS $$
> SELECT id FROM table_a;
> $$ LANGUAGE sql SET search_path = alpha;
> ERROR: relation "table_a" does not exist

Hmmm, I'll bet the validator forgets to apply the parameter modification.

In plpgsql we had to dumb down the validator to do only a bare
syntax check and not any semantic validation. Perhaps SQL function
validation should act the same? You can certainly think of plenty
of other reasons why a full semantics check might fail at function
definition time.

regards, tom lane