aggregate_test.go

// Copyright 2015 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 executor_test

import (
	. "github.com/pingcap/check"
	"github.com/pingcap/tidb/ast"
	"github.com/pingcap/tidb/executor"
	"github.com/pingcap/tidb/expression"
	"github.com/pingcap/tidb/plan"
	"github.com/pingcap/tidb/terror"
	"github.com/pingcap/tidb/util/testkit"
)

type MockExec struct {
	fields    []*ast.ResultField
	Rows      []executor.Row
	curRowIdx int
}

func (m *MockExec) Schema() *expression.Schema {
	return expression.NewSchema()
}

func (m *MockExec) Next() (executor.Row, error) {
	if m.curRowIdx >= len(m.Rows) {
		return nil, nil
	}
	r := m.Rows[m.curRowIdx]
	m.curRowIdx++
	if len(m.fields) > 0 {
		for i, d := range r {
			m.fields[i].Expr.SetValue(d.GetValue())
		}
	}
	return r, nil
}

func (m *MockExec) Close() error {
	m.curRowIdx = 0
	return nil
}

func (m *MockExec) Open() error {
	m.curRowIdx = 0
	return nil
}

func (s *testSuite) TestAggregation(c *C) {
	plan.JoinConcurrency = 1
	defer func() {
		plan.JoinConcurrency = 5
	}()
	tk := testkit.NewTestKit(c, s.store)
	tk.MustExec("use test")
	tk.MustExec("drop table if exists t")
	tk.MustExec("create table t (c int, d int)")
	tk.MustExec("insert t values (NULL, 1)")
	tk.MustExec("insert t values (1, 1)")
	tk.MustExec("insert t values (1, 2)")
	tk.MustExec("insert t values (1, 3)")
	tk.MustExec("insert t values (1, 1)")
	tk.MustExec("insert t values (3, 2)")
	tk.MustExec("insert t values (4, 3)")
	result := tk.MustQuery("select count(*) from t")
	result.Check(testkit.Rows("7"))
	result = tk.MustQuery("select count(*) from t group by d")
	result.Check(testkit.Rows("3", "2", "2"))
	result = tk.MustQuery("select distinct 99 from t group by d having d > 0")
	result.Check(testkit.Rows("99"))
	result = tk.MustQuery("select count(*) from t having 1 = 0")
	result.Check(testkit.Rows())
	result = tk.MustQuery("select c,d from t group by d")
	result.Check(testkit.Rows("<nil> 1", "1 2", "1 3"))
	result = tk.MustQuery("select - c, c as d from t group by c having null not between c and avg(distinct d) - d")
	result.Check(testkit.Rows())
	result = tk.MustQuery("select - c as c from t group by c having t.c > 5")
	result.Check(testkit.Rows())
	result = tk.MustQuery("select t1.c from t t1, t t2 group by c having c > 5")
	result.Check(testkit.Rows())
	result = tk.MustQuery("select count(*) from (select d, c from t) k where d != 0 group by d")
	result.Check(testkit.Rows("3", "2", "2"))
	result = tk.MustQuery("select c as a from t group by d having a < 0")
	result.Check(testkit.Rows())
	result = tk.MustQuery("select c as a from t group by d having sum(a) = 2")
	result.Check(testkit.Rows("<nil>"))
	result = tk.MustQuery("select count(distinct c) from t group by d")
	result.Check(testkit.Rows("1", "2", "2"))
	result = tk.MustQuery("select sum(c) from t group by d")
	result.Check(testkit.Rows("2", "4", "5"))
	result = tk.MustQuery("select sum(c), sum(c+1), sum(c), sum(c+1) from t group by d")
	result.Check(testkit.Rows("2 4 2 4", "4 6 4 6", "5 7 5 7"))
	result = tk.MustQuery("select count(distinct c,d) from t")
	result.Check(testkit.Rows("5"))
	_, err := tk.Exec("select count(c,d) from t")
	c.Assert(err, NotNil)
	result = tk.MustQuery("select d*2 as ee, sum(c) from t group by ee")
	result.Check(testkit.Rows("2 2", "4 4", "6 5"))
	result = tk.MustQuery("select sum(distinct c) from t group by d")
	result.Check(testkit.Rows("1", "4", "5"))
	result = tk.MustQuery("select min(c) from t group by d")
	result.Check(testkit.Rows("1", "1", "1"))
	result = tk.MustQuery("select max(c) from t group by d")
	result.Check(testkit.Rows("1", "3", "4"))
	result = tk.MustQuery("select avg(c) from t group by d")
	result.Check(testkit.Rows("1.0000", "2.0000", "2.5000"))
	result = tk.MustQuery("select d, d + 1 from t group by d")
	result.Check(testkit.Rows("1 2", "2 3", "3 4"))
	result = tk.MustQuery("select count(*) from t")
	result.Check(testkit.Rows("7"))
	result = tk.MustQuery("select count(distinct d) from t")
	result.Check(testkit.Rows("3"))
	result = tk.MustQuery("select count(*) from t group by d having sum(c) > 3")
	result.Check(testkit.Rows("2", "2"))
	result = tk.MustQuery("select max(c) from t group by d having sum(c) > 3 order by avg(c) desc")
	result.Check(testkit.Rows("4", "3"))
	result = tk.MustQuery("select sum(-1) from t a left outer join t b on not null is null")
	result.Check(testkit.Rows("-7"))
	result = tk.MustQuery("select count(*), b.d from t a left join t b on a.c = b.d group by b.d order by b.d")
	result.Check(testkit.Rows("2 <nil>", "12 1", "2 3"))
	result = tk.MustQuery("select count(b.d), b.d from t a left join t b on a.c = b.d group by b.d order by b.d")
	result.Check(testkit.Rows("0 <nil>", "12 1", "2 3"))
	result = tk.MustQuery("select count(b.d), b.d from t b right join t a on a.c = b.d group by b.d order by b.d")
	result.Check(testkit.Rows("0 <nil>", "12 1", "2 3"))
	result = tk.MustQuery("select count(*), b.d from t b right join t a on a.c = b.d group by b.d order by b.d")
	result.Check(testkit.Rows("2 <nil>", "12 1", "2 3"))
	result = tk.MustQuery("select max(case when b.d is null then 10 else b.c end), b.d from t b right join t a on a.c = b.d group by b.d order by b.d")
	result.Check(testkit.Rows("10 <nil>", "1 1", "4 3"))
	result = tk.MustQuery("select count(*) from t a , t b")
	result.Check(testkit.Rows("49"))
	result = tk.MustQuery("select count(*) from t a , t b, t c")
	result.Check(testkit.Rows("343"))
	result = tk.MustQuery("select count(*) from t a , t b where a.c = b.d")
	result.Check(testkit.Rows("14"))
	result = tk.MustQuery("select count(a.d), sum(b.c) from t a , t b where a.c = b.d")
	result.Check(testkit.Rows("14 13"))
	result = tk.MustQuery("select count(*) from t a , t b, t c where a.c = b.d and b.d = c.d")
	result.Check(testkit.Rows("40"))
	result = tk.MustQuery("select count(*), a.c from t a , t b, t c where a.c = b.d and b.d = c.d group by c.d order by a.c")
	result.Check(testkit.Rows("36 1", "4 3"))
	result = tk.MustQuery("select count(a.c), c.d from t a , t b, t c where a.c = b.d and b.d = c.d group by c.d order by c.d")
	result.Check(testkit.Rows("36 1", "4 3"))
	result = tk.MustQuery("select count(*) from t a , t b where a.c = b.d and a.c + b.d = 2")
	result.Check(testkit.Rows("12"))
	result = tk.MustQuery("select count(*) from t a join t b having sum(a.c) < 0")
	result.Check(testkit.Rows())
	result = tk.MustQuery("select count(*) from t a join t b where a.c < 0")
	result.Check(testkit.Rows("0"))
	result = tk.MustQuery("select sum(b.c), count(b.d), a.c from t a left join t b on a.c = b.d group by b.d order by b.d")
	result.Check(testkit.Rows("<nil> 0 <nil>", "8 12 1", "5 2 3"))
	// This two cases prove that having always resolve name from field list firstly.
	result = tk.MustQuery("select 1-d as d from t having d < 0 order by d desc")
	result.Check(testkit.Rows("-1", "-1", "-2", "-2"))
	result = tk.MustQuery("select 1-d as d from t having d + 1 < 0 order by d + 1")
	result.Check(testkit.Rows("-2", "-2"))
	tk.MustExec("drop table if exists t")
	tk.MustExec("create table t (keywords varchar(20), type int)")
	tk.MustExec("insert into t values('测试', 1), ('test', 2)")
	result = tk.MustQuery("select group_concat(keywords) from t group by type order by type")
	result.Check(testkit.Rows("测试", "test"))
	tk.MustExec("drop table if exists t")
	tk.MustExec("create table t (c int, d int)")
	tk.MustExec("insert t values (1, -1)")
	tk.MustExec("insert t values (1, 0)")
	tk.MustExec("insert t values (1, 1)")
	result = tk.MustQuery("select d, d*d as d from t having d = -1")
	result.Check(testkit.Rows())
	result = tk.MustQuery("select d*d as d from t group by d having d = -1")
	result.Check(testkit.Rows("1"))
	result = tk.MustQuery("select d, 1-d as d, c as d from t order by d")
	result.Check(testkit.Rows("1 0 1", "0 1 1", "-1 2 1"))
	result = tk.MustQuery("select d, 1-d as d, c as d from t order by d+1")
	result.Check(testkit.Rows("-1 2 1", "0 1 1", "1 0 1"))
	result = tk.MustQuery("select d, 1-d as d, c as d from t group by d")
	result.Check(testkit.Rows("-1 2 1", "0 1 1", "1 0 1"))
	result = tk.MustQuery("select d as d1, t.d as d1, 1-d as d1, c as d1 from t having d1 < 10")
	result.Check(testkit.Rows("-1 -1 2 1", "0 0 1 1", "1 1 0 1"))
	result = tk.MustQuery("select d*d as d1, c as d1 from t group by d1")
	result.Check(testkit.Rows("1 1", "0 1"))
	result = tk.MustQuery("select d*d as d1, c as d1 from t group by 2")
	result.Check(testkit.Rows("1 1"))
	result = tk.MustQuery("select * from t group by 2")
	result.Check(testkit.Rows("1 -1", "1 0", "1 1"))
	result = tk.MustQuery("select * , sum(d) from t group by 1")
	result.Check(testkit.Rows("1 -1 0"))
	result = tk.MustQuery("select sum(d), t.* from t group by 2")
	result.Check(testkit.Rows("0 1 -1"))
	result = tk.MustQuery("select d as d, c as d from t group by d + 1")
	result.Check(testkit.Rows("-1 1", "0 1", "1 1"))
	result = tk.MustQuery("select c as d, c as d from t group by d")
	result.Check(testkit.Rows("1 1", "1 1", "1 1"))
	_, err = tk.Exec("select d as d, c as d from t group by d")
	c.Assert(err, NotNil)
	_, err = tk.Exec("select t.d, c as d from t group by d")
	c.Assert(err, NotNil)
	result = tk.MustQuery("select *, c+1 as d from t group by 3")
	result.Check(testkit.Rows("1 -1 2"))
	tk.MustExec("drop table if exists t1")
	tk.MustExec("create table t1(a float, b int default 3)")
	tk.MustExec("insert into t1 (a) values (2), (11), (8)")
	result = tk.MustQuery("select min(a), min(case when 1=1 then a else NULL end), min(case when 1!=1 then NULL else a end) from t1 where b=3 group by b")
	result.Check(testkit.Rows("2 2 2"))
	// The following cases use streamed aggregation.
	tk.MustExec("drop table if exists t1")
	tk.MustExec("create table t1(a int, index(a))")
	tk.MustExec("insert into t1 (a) values (1),(2),(3),(4),(5)")
	result = tk.MustQuery("select count(a) from t1 where a < 3")
	result.Check(testkit.Rows("2"))
	tk.MustExec("drop table if exists t1")
	tk.MustExec("create table t1(a int, b int, index(a))")
	result = tk.MustQuery("select sum(b) from (select * from t1) t group by a")
	result.Check(testkit.Rows())
	result = tk.MustQuery("select sum(b) from (select * from t1) t")
	result.Check(testkit.Rows("<nil>"))
	tk.MustExec("insert into t1 (a, b) values (1, 1),(2, 2),(3, 3),(1, 4),(3, 5)")
	result = tk.MustQuery("select avg(b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("2.5000", "2.0000", "4.0000"))
	result = tk.MustQuery("select sum(b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("5", "2", "8"))
	result = tk.MustQuery("select count(b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("2", "1", "2"))
	result = tk.MustQuery("select max(b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("4", "2", "5"))
	result = tk.MustQuery("select min(b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("1", "2", "3"))
	tk.MustExec("drop table if exists t1")
	tk.MustExec("create table t1(a int, b int, index(a,b))")
	tk.MustExec("insert into t1 (a, b) values (1, 1),(2, 2),(3, 3),(1, 4), (1,1),(3, 5), (2,2), (3,5), (3,3)")
	result = tk.MustQuery("select avg(distinct b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("2.5000", "2.0000", "4.0000"))
	result = tk.MustQuery("select sum(distinct b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("5", "2", "8"))
	result = tk.MustQuery("select count(distinct b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("2", "1", "2"))
	result = tk.MustQuery("select max(distinct b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("4", "2", "5"))
	result = tk.MustQuery("select min(distinct b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("1", "2", "3"))
	tk.MustExec("drop table if exists t1")
	tk.MustExec("create table t1(a int, b int, index(b, a))")
	tk.MustExec("insert into t1 (a, b) values (1, 1),(2, 2),(3, 3),(1, 4), (1,1),(3, 5), (2,2), (3,5), (3,3)")
	result = tk.MustQuery("select avg(distinct b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("2.5000", "2.0000", "4.0000"))
	result = tk.MustQuery("select sum(distinct b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("5", "2", "8"))
	result = tk.MustQuery("select count(distinct b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("2", "1", "2"))
	result = tk.MustQuery("select max(distinct b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("4", "2", "5"))
	result = tk.MustQuery("select min(distinct b) from (select * from t1) t group by a")
	result.Check(testkit.Rows("1", "2", "3"))
	tk.MustExec("drop table if exists t")
	tk.MustExec("create table t (id int primary key, ds date)")
	tk.MustExec("insert into t (id, ds) values (1, \"1991-09-05\"),(2,\"1991-09-05\"), (3, \"1991-09-06\"),(0,\"1991-09-06\")")
	result = tk.MustQuery("select sum(id), ds from t group by ds order by id")
	result.Check(testkit.Rows("3 1991-09-06", "3 1991-09-05"))
	tk.MustExec("drop table if exists t1")
	tk.MustExec("drop table if exists t2")
	tk.MustExec("create table t1 (col0 int, col1 int)")
	tk.MustExec("create table t2 (col0 int, col1 int)")
	tk.MustExec("insert into t1 values(83, 0), (26, 0), (43, 81)")
	tk.MustExec("insert into t2 values(22, 2), (3, 12), (38, 98)")
	result = tk.MustQuery("SELECT COALESCE ( + 1, cor0.col0 ) + - CAST( NULL AS DECIMAL ) FROM t2, t1 AS cor0, t2 AS cor1 GROUP BY cor0.col1")
	result.Check(testkit.Rows("<nil>", "<nil>"))

	result = tk.MustQuery("select count(*) from information_schema.columns")
	// When adding new memory table in information_schema, please update this variable.
	columnCountOfAllInformationSchemaTables := "742"
	result.Check(testkit.Rows(columnCountOfAllInformationSchemaTables))

	tk.MustExec("drop table if exists t1")
	tk.MustExec("drop table if exists t2")
	tk.MustExec("create table t1 (c1 int)")
	tk.MustExec("create table t2 (c1 int)")
	tk.MustExec("insert into t1 values(3), (2)")
	tk.MustExec("insert into t2 values(1), (2)")
	tk.MustExec("set @@session.tidb_opt_insubquery_unfold = 1")
	result = tk.MustQuery("select sum(c1 in (select * from t2)) from t1")
	result.Check(testkit.Rows("1"))
	tk.MustExec("set @@session.tidb_opt_insubquery_unfold = 0")
	result = tk.MustQuery("select sum(c1 in (select * from t2)) from t1")
	result.Check(testkit.Rows("1"))
	result = tk.MustQuery("select sum(c1) k from (select * from t1 union all select * from t2)t group by c1 * 2 order by k")
	result.Check(testkit.Rows("1", "3", "4"))
	tk.MustExec("drop table if exists t")
	tk.MustExec("create table t (a int, b int, c int)")
	tk.MustExec("insert into t values(1, 2, 3), (1, 2, 4)")
	result = tk.MustQuery("select count(distinct c), count(distinct a,b) from t")
	result.Check(testkit.Rows("2 1"))

	tk.MustExec("create table idx_agg (a int, b int, index (b))")
	tk.MustExec("insert idx_agg values (1, 1), (1, 2), (2, 2)")
	tk.MustQuery("select sum(a), sum(b) from idx_agg where b > 0 and b < 10").Check(testkit.Rows("4 5"))

	// test without any aggregate function
	tk.MustQuery("select 10 from idx_agg group by b").Check(testkit.Rows("10", "10"))
	tk.MustQuery("select 11 from idx_agg group by a").Check(testkit.Rows("11", "11"))
}

func (s *testSuite) TestAggPrune(c *C) {
	tk := testkit.NewTestKit(c, s.store)
	tk.MustExec("use test")
	tk.MustExec("drop table if exists t")
	tk.MustExec("create table t(id int primary key, b varchar(50), c int)")
	tk.MustExec("insert into t values(1, '1ff', NULL), (2, '234.02', 1)")
	tk.MustQuery("select id, sum(b) from t group by id").Check(testkit.Rows("1 1", "2 234.02"))
	tk.MustQuery("select id, count(c) from t group by id").Check(testkit.Rows("1 0", "2 1"))
	tk.MustExec("drop table if exists t")
	tk.MustExec("create table t(id int primary key, b float, c float)")
	tk.MustExec("insert into t values(1, 1, 3), (2, 1, 6)")
	tk.MustQuery("select sum(b/c) from t group by id").Check(testkit.Rows("0.3333333333333333", "0.16666666666666666"))
	tk.MustExec("drop table if exists t")
	tk.MustExec("create table t(id int primary key, b float, c float, d float)")
	tk.MustExec("insert into t values(1, 1, 3, NULL), (2, 1, NULL, 6), (3, NULL, 1, 2), (4, NULL, NULL, 1), (5, NULL, 2, NULL), (6, 3, NULL, NULL), (7, NULL, NULL, NULL), (8, 1, 2 ,3)")
	tk.MustQuery("select count(distinct b, c, d) from t group by id").Check(testkit.Rows("0", "0", "0", "0", "0", "0", "0", "1"))
}

func (s *testSuite) TestSelectDistinct(c *C) {
	tk := testkit.NewTestKit(c, s.store)
	tk.MustExec("use test")
	s.fillData(tk, "select_distinct_test")

	tk.MustExec("begin")
	r := tk.MustQuery("select distinct name from select_distinct_test;")
	r.Check(testkit.Rows("hello"))
	tk.MustExec("commit")

}

func (s *testSuite) TestAggPushDown(c *C) {
	tk := testkit.NewTestKit(c, s.store)
	tk.MustExec("use test")
	tk.MustExec("drop table if exists t, tt")
	tk.MustExec("create table t(a int primary key, b int, c int)")
	tk.MustExec("create table tt(a int primary key, b int, c int)")
	tk.MustExec("insert into t values(1, 1, 1), (2, 1, 1)")
	tk.MustExec("insert into tt values(1, 2, 1)")
	tk.MustQuery("select max(a.b), max(b.b) from t a join tt b on a.a = b.a group by a.c").Check(testkit.Rows("1 2"))
	tk.MustQuery("select a, count(b) from (select * from t union all select * from tt) k group by a").Check(testkit.Rows("1 2", "2 1"))
}

func (s *testSuite) TestOnlyFullGroupBy(c *C) {
	tk := testkit.NewTestKit(c, s.store)
	tk.MustExec("use test")
	tk.MustExec("set sql_mode = 'ONLY_FULL_GROUP_BY'")
	tk.MustExec("drop table if exists t")
	tk.MustExec("create table t(a int not null primary key, b int not null, c int default null, d int not null, unique key I_b_c (b,c), unique key I_b_d (b,d))")
	tk.MustExec("create table x(a int not null primary key, b int not null, c int default null, d int not null, unique key I_b_c (b,c), unique key I_b_d (b,d))")

	// test AggregateFunc
	tk.MustQuery("select max(a) from t group by d")
	// test incompatible with sql_mode = ONLY_FULL_GROUP_BY
	var err error
	_, err = tk.Exec("select * from t group by d")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select b-c from t group by b+c")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select (b-c)*(b+c), min(a) from t group by b+c, b-c")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select b between c and d from t group by b,c")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select case b when 1 then c when 2 then d else d end from t group by b,c")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select c > (select b from t) from t group by b")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select c is null from t group by b")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select c is true from t group by b")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select (c+b)*d from t group by c,d")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select b in (c,d) from t group by b,c")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select b like '%a' from t group by c")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select c REGEXP '1.*' from t group by b")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select -b from t group by c")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	// test compatible with sql_mode = ONLY_FULL_GROUP_BY
	tk.MustQuery("select a from t group by a,b,c")
	tk.MustQuery("select b from t group by b")
	tk.MustQuery("select b as e from t group by b")
	tk.MustQuery("select b+c from t group by b+c")
	tk.MustQuery("select b+c, min(a) from t group by b+c, b-c")
	tk.MustQuery("select b+c, min(a) from t group by b, c")
	tk.MustQuery("select b+c from t group by b,c")
	tk.MustQuery("select b between c and d from t group by b,c,d")
	tk.MustQuery("select case b when 1 then c when 2 then d else d end from t group by b,c,d")
	tk.MustQuery("select c > (select b from t) from t group by c")
	tk.MustQuery("select exists (select * from t) from t group by d;")
	tk.MustQuery("select c is null from t group by c")
	tk.MustQuery("select c is true from t group by c")
	tk.MustQuery("select (c+b)*d from t group by c,b,d")
	tk.MustQuery("select b in (c,d) from t group by b,c,d")
	tk.MustQuery("select b like '%a' from t group by b")
	tk.MustQuery("select c REGEXP '1.*' from t group by c")
	tk.MustQuery("select -b from t group by b")
	// test functinal depend on primary key
	tk.MustQuery("select * from t group by a")
	// test functional depend on unique not null columns
	tk.MustQuery("select * from t group by b,d")
	// test functional depend on a unique null column
	_, err = tk.Exec("select * from t group by b,c")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	// test functional dependency derived from keys in where condition
	tk.MustQuery("select * from t where c = d group by b, c")
	tk.MustQuery("select t.*, x.* from t, x where t.a = x.a group by t.a")
	tk.MustQuery("select t.*, x.* from t, x where t.b = x.b and t.d = x.d group by t.b, t.d")
	tk.MustQuery("select t.*, x.* from t, x where t.b = x.a group by t.b, t.d")
	tk.MustQuery("select t.b, x.* from t, x where t.b = x.a group by t.b")
	_, err = tk.Exec("select t.*, x.* from t, x where t.c = x.a group by t.b, t.c")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	// test functional dependency derived from keys in join
	tk.MustQuery("select t.*, x.* from t inner join x on t.a = x.a group by t.a")
	tk.MustQuery("select t.*, x.* from t inner join x  on (t.b = x.b and t.d = x.d) group by t.b, x.d")
	tk.MustQuery("select t.b, x.* from t inner join x on t.b = x.b group by t.b, x.d")
	tk.MustQuery("select t.b, x.* from t left join x on t.b = x.b group by t.b, x.d")
	tk.MustQuery("select t.b, x.* from t left join x on x.b = t.b group by t.b, x.d")
	tk.MustQuery("select x.b, t.* from t right join x on x.b = t.b group by x.b, t.d")
	tk.MustQuery("select x.b, t.* from t right join x on t.b = x.b group by x.b, t.d")
	_, err = tk.Exec("select t.b, x.* from t right join x on t.b = x.b group by t.b, x.d")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	_, err = tk.Exec("select t.b, x.* from t right join x on t.b = x.b group by t.b, x.d")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	// test functional dependency of derived table
	tk.MustQuery("select * from (select * from t) as e group by a")
	tk.MustQuery("select * from (select * from t) as e group by b,d")
	_, err = tk.Exec("select * from (select * from t) as e group by b,c")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	// test order by
	tk.MustQuery("select c from t group by c,d order by d")
	_, err = tk.Exec("select c from t group by c order by d")
	c.Assert(terror.ErrorEqual(err, plan.ErrFieldNotInGroupBy), IsTrue)
	// test ambiguous column
	_, err = tk.Exec("select c from t,x group by t.c")
	c.Assert(terror.ErrorEqual(err, plan.ErrAmbiguous), IsTrue)
}

func (s *testSuite) TestHaving(c *C) {
	tk := testkit.NewTestKitWithInit(c, s.store)

	tk.MustExec("set sql_mode = 'STRICT_TRANS_TABLES,NO_ENGINE_SUBSTITUTION'")
	tk.MustExec("drop table if exists t")
	tk.MustExec("create table t (c1 int, c2 int, c3 int)")
	tk.MustExec("insert into t values (1,2,3), (2, 3, 1), (3, 1, 2)")

	tk.MustQuery("select c1 as c2, c3 from t having c2 = 2").Check(testkit.Rows("2 1"))
	tk.MustQuery("select c1 as c2, c3 from t group by c2 having c2 = 2;").Check(testkit.Rows("1 3"))
	tk.MustQuery("select c1 as c2, c3 from t group by c2 having sum(c2) = 2;").Check(testkit.Rows("1 3"))
	tk.MustQuery("select c1 as c2, c3 from t group by c3 having sum(c2) = 2;").Check(testkit.Rows("1 3"))
	tk.MustQuery("select c1 as c2, c3 from t group by c3 having sum(0) + c2 = 2;").Check(testkit.Rows("2 1"))
	tk.MustQuery("select c1 as a from t having c1 = 1;").Check(testkit.Rows("1"))
	tk.MustQuery("select t.c1 from t having c1 = 1;").Check(testkit.Rows("1"))
	tk.MustQuery("select a.c1 from t as a having c1 = 1;").Check(testkit.Rows("1"))
	tk.MustQuery("select c1 as a from t group by c3 having sum(a) = 1;").Check(testkit.Rows("1"))
	tk.MustQuery("select c1 as a from t group by c3 having sum(a) + a = 2;").Check(testkit.Rows("1"))
	tk.MustQuery("select a.c1 as c, a.c1 as d from t as a, t as b having c1 = 1 limit 1;").Check(testkit.Rows("1 1"))

	tk.MustQuery("select sum(c1) from t group by c1 having sum(c1)").Check(testkit.Rows("1", "2", "3"))
	tk.MustQuery("select sum(c1) - 1 from t group by c1 having sum(c1) - 1").Check(testkit.Rows("1", "2"))
	tk.MustQuery("select 1 from t group by c1 having sum(abs(c2 + c3)) = c1").Check(testkit.Rows("1"))
}