CREATE FUNCTION "foo_impl"("query_p" TEXT, "search_path_p" TEXT)
RETURNS "some_type"
LANGUAGE plpgsql SET search_path FROM CURRENT AS $$
DECLARE
"old_search_path" TEXT;
"result" "some_type";
BEGIN
"old_search_path" = current_setting('search_path');
PERFORM set_config('search_path', "search_path_p", TRUE);
EXECUTE "query_p" INTO "result";
PERFORM set_config('search_path', "old_search_path", TRUE);
RETURN "result";
END;
$$;
You might consider adding a polymorphic argument for the result type. Then if you call the function with two different typed inputs it will be cached once for each.
“ Likewise, functions having polymorphic argument types have a separate statement cache for each combination of actual argument types they have been invoked for, so that data type differences do not cause unexpected failures.”
David J.
