// Copyright 2019 PingCAP, Inc. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // See the License for the specific language governing permissions and // limitations under the License. package expression_test import ( . "github.com/pingcap/check" "github.com/pingcap/tidb/util/testkit" ) func (s *testIntegrationSuite) TestFoldIfNull(c *C) { tk := testkit.NewTestKit(c, s.store) tk.MustExec(`use test;`) tk.MustExec(`drop table if exists t;`) tk.MustExec(`create table t(a bigint, b bigint);`) tk.MustExec(`insert into t values(1, 1);`) tk.MustQuery(`desc select ifnull("aaaa", a) from t;`).Check(testkit.Rows( `Projection_3 10000.00 root aaaa->Column#4`, `└─TableReader_5 10000.00 root data:TableFullScan_4`, ` └─TableFullScan_4 10000.00 cop[tikv] table:t keep order:false, stats:pseudo`, )) tk.MustQuery(`show warnings;`).Check(testkit.Rows()) tk.MustQuery(`select ifnull("aaaa", a) from t;`).Check(testkit.Rows("aaaa")) tk.MustQuery(`show warnings;`).Check(testkit.Rows()) }