postgresql - ERROR: permission denied for language c

Question

When creating a function like this with a non-super user I am getting the error below:

ERROR: permission denied for language c SQL state: 42501

The function created is :

CREATE OR REPLACE FUNCTION dblink_connect (text)
RETURNS text
AS '$libdir/dblink','dblink_connect'
LANGUAGE C STRICT;

But if I wanted to give permission on language C to my non-super user, I am getting the error below: postgres=# grant usage on language c to caixa; ERROR: language "c" is not trusted

That means, non-super user can't create function with language C? or is there anything else I am doing wrong?

Answer 1

That's right, according to doc:

Only superusers can create functions in untrusted languages

Quick check:

SELECT lanpltrusted FROM pg_language WHERE lanname LIKE 'c';
 lanpltrusted 
--------------
 f
(1 row)

If you really want this, then you could modify pg_language system catalog (ALTER LANGUAGE doesn't have such option):

UPDATE pg_language SET lanpltrusted = true WHERE lanname LIKE 'c';

Per user @Otheus below: the UPDATE statement must be done in the DB where the function will reside.