executor: add correctness tests about IndexMerge

executor/partition_table_test.go

@@ -1328,6 +1328,101 @@ func (s *partitionTableSuite) TestDirectReadingWithAgg(c *C) {
 	}
 }
 
+func (s *partitionTableSuite) TestIdexMerge(c *C) {
+	if israce.RaceEnabled {
+		c.Skip("exhaustive types test, skip race test")
+	}
+
+	tk := testkit.NewTestKitWithInit(c, s.store)
+	tk.MustExec("create database test_idx_merge")
+	tk.MustExec("use test_idx_merge")
+	tk.MustExec("set @@tidb_partition_prune_mode = 'dynamic'")
+
+	// list partition table
+	tk.MustExec(`create table tlist(a int, b int, primary key(a) clustered, index idx_b(b)) partition by list(a)(
+		partition p0 values in (1, 2, 3, 4),
+		partition p1 values in (5, 6, 7, 8),
+		partition p2 values in (9, 10, 11, 12));`)
+
+	// range partition table
+	tk.MustExec(`create table trange(a int, b int, primary key(a) clustered, index idx_b(b)) partition by range(a) (
+		partition p0 values less than(300),
+		partition p1 values less than (500),
+		partition p2 values less than(1100));`)
+
+	// hash partition table
+	tk.MustExec(`create table thash(a int, b int, primary key(a) clustered, index idx_b(b)) partition by hash(a) partitions 4;`)
+
+	// regular table
+	tk.MustExec("create table tregular1(a int, b int, primary key(a) clustered)")
+	tk.MustExec("create table tregular2(a int, b int, primary key(a) clustered)")
+
+	// generate some random data to be inserted
+	vals := make([]string, 0, 2000)
+	for i := 0; i < 2000; i++ {
+		vals = append(vals, fmt.Sprintf("(%v, %v)", rand.Intn(1100), rand.Intn(2000)))
+	}
+
+	tk.MustExec("insert ignore into trange values " + strings.Join(vals, ","))
+	tk.MustExec("insert ignore into thash values " + strings.Join(vals, ","))
+	tk.MustExec("insert ignore into tregular1 values " + strings.Join(vals, ","))
+
+	vals = make([]string, 0, 2000)
+	for i := 0; i < 2000; i++ {
+		vals = append(vals, fmt.Sprintf("(%v, %v)", rand.Intn(12)+1, rand.Intn(20)))
+	}
+
+	tk.MustExec("insert ignore into tlist values " + strings.Join(vals, ","))
+	tk.MustExec("insert ignore into tregular2 values " + strings.Join(vals, ","))
+
+	// test range partition
+	for i := 0; i < 100; i++ {
+		x1 := rand.Intn(1099)
+		x2 := rand.Intn(1099)
+
+		queryPartition1 := fmt.Sprintf("select /*+ use_index_merge(trange) */ * from trange where a > %v or b < %v;", x1, x2)
+		queryRegular1 := fmt.Sprintf("select /*+ use_index_merge(tregular1) */ * from tregular1 where a > %v or b < %v;", x1, x2)
+		c.Assert(tk.HasPlan(queryPartition1, "IndexMerge"), IsTrue) // check if IndexLookUp is used
+		tk.MustQuery(queryPartition1).Sort().Check(tk.MustQuery(queryRegular1).Sort().Rows())
+
+		queryPartition2 := fmt.Sprintf("select /*+ use_index_merge(trange) */ * from trange where a > %v or b > %v;", x1, x2)
+		queryRegular2 := fmt.Sprintf("select /*+ use_index_merge(tregular1) */ * from tregular1 where a > %v or b > %v;", x1, x2)
+		c.Assert(tk.HasPlan(queryPartition2, "IndexMerge"), IsTrue) // check if IndexLookUp is used
+		tk.MustQuery(queryPartition2).Sort().Check(tk.MustQuery(queryRegular2).Sort().Rows())
+	}
+
+	// test hash partition
+	for i := 0; i < 100; i++ {
+		x1 := rand.Intn(1099)
+		x2 := rand.Intn(1099)
+
+		queryPartition1 := fmt.Sprintf("select /*+ use_index_merge(thash) */ * from thash where a > %v or b < %v;", x1, x2)
+		queryRegular1 := fmt.Sprintf("select /*+ use_index_merge(tregualr1) */ * from tregular1 where a > %v or b < %v;", x1, x2)
+		c.Assert(tk.HasPlan(queryPartition1, "IndexMerge"), IsTrue) // check if IndexLookUp is used
+		tk.MustQuery(queryPartition1).Sort().Check(tk.MustQuery(queryRegular1).Sort().Rows())
+
+		queryPartition2 := fmt.Sprintf("select /*+ use_index_merge(thash) */ * from thash where a > %v or b > %v;", x1, x2)
+		queryRegular2 := fmt.Sprintf("select /*+ use_index_merge(tregular1) */ * from tregular1 where a > %v or b > %v;", x1, x2)
+		c.Assert(tk.HasPlan(queryPartition2, "IndexMerge"), IsTrue) // check if IndexLookUp is used
+		tk.MustQuery(queryPartition2).Sort().Check(tk.MustQuery(queryRegular2).Sort().Rows())
+	}
+
+	// test list partition
+	for i := 0; i < 100; i++ {
+		x1 := rand.Intn(12) + 1
+		x2 := rand.Intn(12) + 1
+		queryPartition1 := fmt.Sprintf("select /*+ use_index_merge(tlist) */ * from tlist where a > %v or b < %v;", x1, x2)
+		queryRegular1 := fmt.Sprintf("select /*+ use_index_merge(tregular2) */ * from tregular2 where a > %v or b < %v;", x1, x2)
+		c.Assert(tk.HasPlan(queryPartition1, "IndexMerge"), IsTrue) // check if IndexLookUp is used
+		tk.MustQuery(queryPartition1).Sort().Check(tk.MustQuery(queryRegular1).Sort().Rows())
+
+		queryPartition2 := fmt.Sprintf("select /*+ use_index_merge(tlist) */ * from tlist where a > %v or b > %v;", x1, x2)
+		queryRegular2 := fmt.Sprintf("select /*+ use_index_merge(tregular2) */ * from tregular2 where a > %v or b > %v;", x1, x2)
+		c.Assert(tk.HasPlan(queryPartition2, "IndexMerge"), IsTrue) // check if IndexLookUp is used
+		tk.MustQuery(queryPartition2).Sort().Check(tk.MustQuery(queryRegular2).Sort().Rows())
+	}
+}
+
 func (s *globalIndexSuite) TestGlobalIndexScan(c *C) {
 	tk := testkit.NewTestKitWithInit(c, s.store)
 	tk.MustExec("drop table if exists p")