Function func_strict

src/backend/utils/cache/lsyscache.c:2392–2405

* func_strict * Given procedure id, return the function's proisstrict flag. */

 *		Given procedure id, return the function's proisstrict flag.
 */
bool
func_strict(Oid funcid)
{
	HeapTuple	tp;
	bool		result;

	tp = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
	if (!HeapTupleIsValid(tp))
		elog(ERROR, "cache lookup failed for function %u", funcid);

	result = ((Form_pg_proc) GETSTRUCT(tp))->proisstrict;
	ReleaseSysCache(tp);
	return result;
}

/*
 * func_volatile