fix by comments

Signed-off-by: guo-shaoge <shaoge1994@163.com>

executor/index_merge_reader_test.go

@@ -170,3 +170,75 @@ func (s *testSuite1) TestPartitionTableRandomIndexMerge(c *C) {
 		tk.MustQuery("select /*+ USE_INDEX_MERGE(tpk, a, b) */ * from tpk where " + cond).Sort().Check(result)
 	}
 }
+
+func (s *testSuite1) TestIndexMergeInTransaction(c *C) {
+	tk := testkit.NewTestKitWithInit(c, s.store)
+	tk.MustExec("drop table if exists t1;")
+	tk.MustExec("create table t1(c1 int, c2 int, c3 int, pk int, key(c1), key(c2), key(c3), primary key(pk));")
+	tk.MustExec("begin;")
+	// Expect two IndexScan(c1, c2).
+	tk.MustQuery("explain select /*+ use_index_merge(t1) */ * from t1 where (c1 < 10 or c2 < 10) and c3 < 10;").Check(testkit.Rows(
+		"IndexMerge_9 1841.86 root  ",
+		"├─IndexRangeScan_5(Build) 3323.33 cop[tikv] table:t1, index:c1(c1) range:[-inf,10), keep order:false, stats:pseudo",
+		"├─IndexRangeScan_6(Build) 3323.33 cop[tikv] table:t1, index:c2(c2) range:[-inf,10), keep order:false, stats:pseudo",
+		"└─Selection_8(Probe) 1841.86 cop[tikv]  lt(test.t1.c3, 10)",
+		"  └─TableRowIDScan_7 5542.21 cop[tikv] table:t1 keep order:false, stats:pseudo"))
+	// Expect one IndexScan(c2) and one TableScan(pk).
+	tk.MustQuery("explain select /*+ use_index_merge(t1) */ * from t1 where (pk < 10 or c2 < 10) and c3 < 10;").Check(testkit.Rows(
+		"IndexMerge_9 1106.67 root  ",
+		"├─TableRangeScan_5(Build) 3333.33 cop[tikv] table:t1 range:[-inf,10), keep order:false, stats:pseudo",
+		"├─IndexRangeScan_6(Build) 3323.33 cop[tikv] table:t1, index:c2(c2) range:[-inf,10), keep order:false, stats:pseudo",
+		"└─Selection_8(Probe) 1106.67 cop[tikv]  lt(test.t1.c3, 10)",
+		"  └─TableRowIDScan_7 3330.01 cop[tikv] table:t1 keep order:false, stats:pseudo"))
+
+	// Test with normal key.
+	tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (c1 < 10 or c2 < 10) and c3 < 10;").Check(testkit.Rows())
+	tk.MustExec("insert into t1 values(1, 1, 1, 1);")
+	tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (c1 < 10 or c2 < 10) and c3 < 10;").Check(testkit.Rows("1 1 1 1"))
+	tk.MustExec("update t1 set c3 = 100 where c3 = 1;")
+	tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (c1 < 10 or c2 < 10) and c3 < 10;").Check(testkit.Rows())
+	tk.MustExec("delete from t1;")
+	tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (c1 < 10 or c2 < 10) and c3 < 10;").Check(testkit.Rows())
+
+	// Test with primary key, so the partialPlan is TableScan.
+	tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (pk < 10 or c2 < 10) and c3 < 10;").Check(testkit.Rows())
+	tk.MustExec("insert into t1 values(1, 1, 1, 1);")
+	tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (pk < 10 or c2 < 10) and c3 < 10;").Check(testkit.Rows("1 1 1 1"))
+	tk.MustExec("update t1 set c3 = 100 where c3 = 1;")
+	tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (pk < 10 or c2 < 10) and c3 < 10;").Check(testkit.Rows())
+	tk.MustExec("delete from t1;")
+	tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (pk < 10 or c2 < 10) and c3 < 10;").Check(testkit.Rows())
+	tk.MustExec("commit;")
+
+	// Test partition table.
+	tk.MustExec("drop table if exists t1;")
+	tk.MustExec(`create table t1(c1 int, c2 int, c3 int, pk int, part int, key(c1), key(c2), key(c3), primary key(pk, part)) 
+			partition by range(part) (
+			partition p0 values less than (10),
+			partition p1 values less than (20),
+			partition p2 values less than (maxvalue))`)
+	tk.MustExec("begin;")
+	tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (c1 < 20 or c2 < 20) and c3 < 20;").Check(testkit.Rows())
+
+	tk.MustExec("insert into t1 values(1, 1, 1, 1, 1);")
+	tk.MustExec("insert into t1 values(11, 11, 11, 11, 11);")
+	tk.MustExec("insert into t1 values(21, 21, 21, 21, 21);")
+	tk.MustExec("insert into t1 values(31, 31, 31, 31, 31);")
+	res := tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (c1 < 20 or c2 < 20) and c3 < 20;").Sort()
+	res.Check(testkit.Rows("1 1 1 1 1", "11 11 11 11 11"))
+	res = tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (pk < 20 or c2 < 20) and c3 < 20;").Sort()
+	res.Check(testkit.Rows("1 1 1 1 1", "11 11 11 11 11"))
+
+	tk.MustExec("update t1 set c3 = 100 where c3 = 1;")
+	res = tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (c1 < 20 or c2 < 20) and c3 < 20;")
+	res.Check(testkit.Rows("11 11 11 11 11"))
+	res = tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (pk < 20 or c2 < 20) and c3 < 20;")
+	res.Check(testkit.Rows("11 11 11 11 11"))
+
+	tk.MustExec("delete from t1;")
+	res = tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (c1 < 20 or c2 < 20) and c3 < 20;")
+	res.Check(testkit.Rows())
+	res = tk.MustQuery("select /*+ use_index_merge(t1) */ * from t1 where (pk < 20 or c2 < 20) and c3 < 20;")
+	res.Check(testkit.Rows())
+	tk.MustExec("commit;")
+}

executor/mem_reader.go

@@ -154,10 +154,9 @@ type memTableReader struct {
 	colIDs        map[int64]int
 	buffer        allocBuf
 	pkColIDs      []int64
-
+	cacheTable    kv.MemBuffer
 	// Used when extracting handles from row in memTableReader.getMemRowsHandle.
 	handleCols plannercore.HandleCols
-	cacheTable kv.MemBuffer
 }
 
 type allocBuf struct {
@@ -316,7 +315,7 @@ func (m *memTableReader) getRowData(handle kv.Handle, value []byte) ([][]byte, e
 	return values, nil
 }
 
-// Used when memIndexMergeReader.partialPlans[i] is TableScan.
+// getMemRowsHandle is called when memIndexMergeReader.partialPlans[i] is TableScan.
 func (m *memTableReader) getMemRowsHandle() ([]kv.Handle, error) {
 	rows, err := m.getMemRows()
 	if err != nil {
@@ -701,7 +700,7 @@ func unionHandles(kvRanges [][]kv.KeyRange, memIndexReaders []*memIndexReader, m
 		return nil, errors.Errorf("len(kvRanges) should be equal to len(memIndexReaders)")
 	}
 	if len(memTableReaders) != len(memIndexReaders) {
-		return nil, errors.Errorf("len(kvRanges) should be equal to len(memIndexReaders)")
+		return nil, errors.Errorf("len(memTableReaders) should be equal to len(memIndexReaders)")
 	}
 
 	hMap := kv.NewHandleMap()