예제 #1
0
파일: funcapi.c 프로젝트: CraigHarris/gpdb
/*
 * assign_func_result_transient_type
 *		assign typmod if the result of function is transient type.
 *
 */
void
assign_func_result_transient_type(Oid funcid)
{
	HeapTuple	tp;
	Form_pg_proc procform;
	TupleDesc	tupdesc;
	cqContext  *pcqCtx;

	pcqCtx = caql_beginscan(
			NULL,
			cql("SELECT * FROM pg_proc "
				" WHERE oid = :1 ",
				ObjectIdGetDatum(funcid)));

	tp = caql_getnext(pcqCtx);

	caql_endscan(pcqCtx);

	if (!HeapTupleIsValid(tp))
		elog(ERROR, "cache lookup failed for function %u", funcid);
	procform = (Form_pg_proc) GETSTRUCT(tp);

	tupdesc = build_function_result_tupdesc_t(tp);
	if (tupdesc == NULL)
		return;

	if (resolve_polymorphic_tupdesc(tupdesc,
									&procform->proargtypes,
									NULL))
	{
		if (tupdesc->tdtypeid == RECORDOID &&
			tupdesc->tdtypmod < 0)
			assign_record_type_typmod(tupdesc);
	}
}
예제 #2
0
파일: funcapi.c 프로젝트: mjw56/postgres
/*
 * internal_get_result_type -- workhorse code implementing all the above
 *
 * funcid must always be supplied.	call_expr and rsinfo can be NULL if not
 * available.  We will return TYPEFUNC_RECORD, and store NULL into
 * *resultTupleDesc, if we cannot deduce the complete result rowtype from
 * the available information.
 */
static TypeFuncClass
internal_get_result_type(Oid funcid,
						 Node *call_expr,
						 ReturnSetInfo *rsinfo,
						 Oid *resultTypeId,
						 TupleDesc *resultTupleDesc)
{
	TypeFuncClass result;
	HeapTuple	tp;
	Form_pg_proc procform;
	Oid			rettype;
	TupleDesc	tupdesc;

	/* First fetch the function's pg_proc row to inspect its rettype */
	tp = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
	if (!HeapTupleIsValid(tp))
		elog(ERROR, "cache lookup failed for function %u", funcid);
	procform = (Form_pg_proc) GETSTRUCT(tp);

	rettype = procform->prorettype;

	/* Check for OUT parameters defining a RECORD result */
	tupdesc = build_function_result_tupdesc_t(tp);
	if (tupdesc)
	{
		/*
		 * It has OUT parameters, so it's basically like a regular composite
		 * type, except we have to be able to resolve any polymorphic OUT
		 * parameters.
		 */
		if (resultTypeId)
			*resultTypeId = rettype;

		if (resolve_polymorphic_tupdesc(tupdesc,
										&procform->proargtypes,
										call_expr))
		{
			if (tupdesc->tdtypeid == RECORDOID &&
				tupdesc->tdtypmod < 0)
				assign_record_type_typmod(tupdesc);
			if (resultTupleDesc)
				*resultTupleDesc = tupdesc;
			result = TYPEFUNC_COMPOSITE;
		}
		else
		{
			if (resultTupleDesc)
				*resultTupleDesc = NULL;
			result = TYPEFUNC_RECORD;
		}

		ReleaseSysCache(tp);

		return result;
	}

	/*
	 * If scalar polymorphic result, try to resolve it.
	 */
	if (IsPolymorphicType(rettype))
	{
		Oid			newrettype = exprType(call_expr);

		if (newrettype == InvalidOid)	/* this probably should not happen */
			ereport(ERROR,
					(errcode(ERRCODE_DATATYPE_MISMATCH),
					 errmsg("could not determine actual result type for function \"%s\" declared to return type %s",
							NameStr(procform->proname),
							format_type_be(rettype))));
		rettype = newrettype;
	}

	if (resultTypeId)
		*resultTypeId = rettype;
	if (resultTupleDesc)
		*resultTupleDesc = NULL;	/* default result */

	/* Classify the result type */
	result = get_type_func_class(rettype);
	switch (result)
	{
		case TYPEFUNC_COMPOSITE:
			if (resultTupleDesc)
				*resultTupleDesc = lookup_rowtype_tupdesc_copy(rettype, -1);
			/* Named composite types can't have any polymorphic columns */
			break;
		case TYPEFUNC_SCALAR:
			break;
		case TYPEFUNC_RECORD:
			/* We must get the tupledesc from call context */
			if (rsinfo && IsA(rsinfo, ReturnSetInfo) &&
				rsinfo->expectedDesc != NULL)
			{
				result = TYPEFUNC_COMPOSITE;
				if (resultTupleDesc)
					*resultTupleDesc = rsinfo->expectedDesc;
				/* Assume no polymorphic columns here, either */
			}
			break;
		default:
			break;
	}

	ReleaseSysCache(tp);

	return result;
}