diff --git a/expression/integration_test.go b/expression/integration_test.go index 31de453b0563b..31a7e1178a2b6 100644 --- a/expression/integration_test.go +++ b/expression/integration_test.go @@ -3688,6 +3688,43 @@ func TestIssue16973(t *testing.T) { "AND t1.status IN (2,6,10) AND timestampdiff(month, t2.begin_time, date'2020-05-06') = 0;").Check(testkit.Rows("1")) } +func TestShardIndexOnTiFlash(t *testing.T) { + store, clean := testkit.CreateMockStore(t) + defer clean() + + tk := testkit.NewTestKit(t, store) + tk.MustExec("use test") + tk.MustExec("drop table if exists t") + tk.MustExec("create table t(id int primary key clustered, a int, b int, unique key uk_expr((tidb_shard(a)),a))") + + // Create virtual tiflash replica info. + dom := domain.GetDomain(tk.Session()) + is := dom.InfoSchema() + db, exists := is.SchemaByName(model.NewCIStr("test")) + require.True(t, exists) + for _, tblInfo := range db.Tables { + if tblInfo.Name.L == "t" { + tblInfo.TiFlashReplica = &model.TiFlashReplicaInfo{ + Count: 1, + Available: true, + } + } + } + tk.MustExec("set @@session.tidb_enforce_mpp = 1") + rows := tk.MustQuery("explain select max(b) from t").Rows() + for _, row := range rows { + line := fmt.Sprintf("%v", row) + require.NotContains(t, line, "tiflash") + } + tk.MustExec("set @@session.tidb_enforce_mpp = 0") + tk.MustExec("set @@session.tidb_allow_mpp = 0") + rows = tk.MustQuery("explain select max(b) from t").Rows() + for _, row := range rows { + line := fmt.Sprintf("%v", row) + require.NotContains(t, line, "tiflash") + } +} + func TestExprPushdownBlacklist(t *testing.T) { store, clean := testkit.CreateMockStore(t) defer clean() diff --git a/planner/core/find_best_task.go b/planner/core/find_best_task.go index c720879d15ed4..249cfdc1f69a6 100644 --- a/planner/core/find_best_task.go +++ b/planner/core/find_best_task.go @@ -1873,6 +1873,19 @@ func (ds *DataSource) convertToTableScan(prop *property.PhysicalProperty, candid if ts.KeepOrder && ts.Desc && ts.StoreType == kv.TiFlash { return invalidTask, nil } + if ts.StoreType == kv.TiFlash { + for _, col := range ts.schema.Columns { + // In theory, TiFlash does not support virtual expr, but in non-mpp mode, if the cop request only contain table scan, then + // TiDB will fill the virtual column after decoding the cop response(executor.FillVirtualColumnValue), that is to say, the virtual + // columns in Cop request is just a placeholder, so TiFlash can support virtual column in cop request mode. However, virtual column + // with TiDBShard is special, it can be added using create index statement, TiFlash's ddl does not handle create index statement, so + // there is a chance that the TiDBShard's virtual column is not seen by TiFlash, in this case, TiFlash will throw column not found error + if ds.containExprPrefixUk && expression.GcColumnExprIsTidbShard(col.VirtualExpr) { + ds.SCtx().GetSessionVars().RaiseWarningWhenMPPEnforced("MPP mode may be blocked because column `" + col.OrigName + "` is a virtual column which is not supported now.") + return invalidTask, nil + } + } + } if prop.TaskTp == property.MppTaskType { if ts.KeepOrder { return invalidTask, nil