planner: do not build MPP plan for scan with virtual columns (#23980)

pingcap · Apr 15, 2021 · 05e584f · 05e584f
1 parent 088f310
commit 05e584f
Show file tree

Hide file tree

Showing 2 changed files with 38 additions and 0 deletions.
diff --git a/executor/tiflash_test.go b/executor/tiflash_test.go
@@ -447,3 +447,36 @@ func (s *tiflashTestSuite) TestMppApply(c *C) {
 	// table range scan with correlated access conditions
 	tk.MustQuery("select /*+ agg_to_cop(), hash_agg()*/ count(*) from x1 where b > any (select x2.a from x2 where x1.a = x2.a);").Check(testkit.Rows("2"))
 }
+
+func (s *tiflashTestSuite) TestTiFlashVirtualColumn(c *C) {
+	tk := testkit.NewTestKit(c, s.store)
+	tk.MustExec("use test")
+	tk.MustExec("drop table if exists t1,t2,t3")
+	tk.MustExec("create table t1 (a bit(4), b bit(4), c bit(4) generated always as (a) virtual)")
+	tk.MustExec("alter table t1 set tiflash replica 1")
+	tb := testGetTableByName(c, tk.Se, "test", "t1")
+	err := domain.GetDomain(tk.Se).DDL().UpdateTableReplicaInfo(tk.Se, tb.Meta().ID, true)
+	c.Assert(err, IsNil)
+	tk.MustExec("insert into t1(a,b) values(b'01',b'01'),(b'10',b'10'),(b'11',b'11')")
+
+	tk.MustExec("create table t2 (a int, b int, c int generated always as (a) virtual)")
+	tk.MustExec("alter table t2 set tiflash replica 1")
+	tb = testGetTableByName(c, tk.Se, "test", "t2")
+	err = domain.GetDomain(tk.Se).DDL().UpdateTableReplicaInfo(tk.Se, tb.Meta().ID, true)
+	c.Assert(err, IsNil)
+	tk.MustExec("insert into t2(a,b) values(1,1),(2,2),(3,3)")
+
+	tk.MustExec("create table t3 (a bit(4), b bit(4), c bit(4) generated always as (b'01'+b'10') virtual)")
+	tk.MustExec("alter table t3 set tiflash replica 1")
+	tb = testGetTableByName(c, tk.Se, "test", "t3")
+	err = domain.GetDomain(tk.Se).DDL().UpdateTableReplicaInfo(tk.Se, tb.Meta().ID, true)
+	c.Assert(err, IsNil)
+	tk.MustExec("insert into t3(a,b) values(b'01',b'01'),(b'10',b'10'),(b'11',b'11')")
+
+	tk.MustExec("set @@session.tidb_isolation_read_engines=\"tiflash\"")
+	tk.MustExec("set @@session.tidb_allow_mpp=ON")
+
+	tk.MustQuery("select /*+ hash_agg() */ count(*) from t1 where c > b'01'").Check(testkit.Rows("2"))
+	tk.MustQuery("select /*+ hash_agg() */ count(*) from t2 where c > 1").Check(testkit.Rows("2"))
+	tk.MustQuery("select /*+ hash_agg() */ count(*) from t3 where c > b'01'").Check(testkit.Rows("3"))
+}
diff --git a/planner/core/find_best_task.go b/planner/core/find_best_task.go
@@ -1538,6 +1538,11 @@ func (ds *DataSource) convertToTableScan(prop *property.PhysicalProperty, candid
 			// If ts is a single partition, then this partition table is in static-only prune, then we should not choose mpp execution.
 			return &mppTask{}, nil
 		}
+		for _, col := range ts.schema.Columns {
+			if col.VirtualExpr != nil {
+				return &mppTask{}, nil
+			}
+		}
 		mppTask := &mppTask{
 			p:      ts,
 			cst:    cost,