*: use CLUSTERED and NONCLUSTERED to control primary key type (#22409)

cmd/ddltest/ddl_test.go

@@ -532,7 +532,7 @@ func (s *TestDDLSuite) Bootstrap(c *C) {
 	tk.MustExec("create table test_mixed (c1 int, c2 int, primary key(c1))")
 	tk.MustExec("create table test_inc (c1 int, c2 int, primary key(c1))")
 
-	tk.MustExec("set @@tidb_enable_clustered_index = 1")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 	tk.MustExec("drop table if exists test_insert_common, test_conflict_insert_common, " +
 		"test_update_common, test_conflict_update_common, test_delete_common, test_conflict_delete_common, " +
 		"test_mixed_common, test_inc_common")
@@ -544,7 +544,7 @@ func (s *TestDDLSuite) Bootstrap(c *C) {
 	tk.MustExec("create table test_conflict_delete_common (c1 int, c2 int, primary key(c1, c2))")
 	tk.MustExec("create table test_mixed_common (c1 int, c2 int, primary key(c1, c2))")
 	tk.MustExec("create table test_inc_common (c1 int, c2 int, primary key(c1, c2))")
-	tk.MustExec("set @@tidb_enable_clustered_index = 0")
+	tk.Se.GetSessionVars().EnableClusteredIndex = false
 }
 
 func (s *TestDDLSuite) TestSimple(c *C) {

cmd/explaintest/main.go

@@ -30,6 +30,7 @@ import (
 	"github.com/pingcap/errors"
 	"github.com/pingcap/log"
 	"github.com/pingcap/parser/ast"
+	"github.com/pingcap/tidb/domain"
 	"github.com/pingcap/tidb/session"
 	"github.com/pingcap/tidb/sessionctx"
 	"github.com/pingcap/tidb/util/logutil"
@@ -656,13 +657,15 @@ func main() {
 		"set @@tidb_window_concurrency=4",
 		"set @@tidb_projection_concurrency=4",
 		"set @@tidb_distsql_scan_concurrency=15",
-		"set @@tidb_enable_clustered_index=0;",
+		"set @@global.tidb_enable_clustered_index=0;",
 	}
 	for _, sql := range resets {
 		if _, err = mdb.Exec(sql); err != nil {
 			log.Fatal(fmt.Sprintf("%s failed", sql), zap.Error(err))
 		}
 	}
+	// Wait global variables to reload.
+	time.Sleep(domain.GlobalVariableCacheExpiry)
 
 	if _, err = mdb.Exec("set sql_mode='STRICT_TRANS_TABLES'"); err != nil {
 		log.Fatal("set sql_mode='STRICT_TRANS_TABLES' failed", zap.Error(err))

ddl/db_integration_test.go

@@ -1577,7 +1577,7 @@ func (s *testIntegrationSuite3) TestAlterColumn(c *C) {
 	c.Assert(err, NotNil)
 	result := tk.MustQuery("show create table mc")
 	createSQL := result.Rows()[0][1]
-	expected := "CREATE TABLE `mc` (\n  `a` int(11) NOT NULL,\n  `b` int(11) DEFAULT NULL,\n  `c` int(11) DEFAULT NULL,\n  PRIMARY KEY (`a`)\n) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"
+	expected := "CREATE TABLE `mc` (\n  `a` int(11) NOT NULL,\n  `b` int(11) DEFAULT NULL,\n  `c` int(11) DEFAULT NULL,\n  PRIMARY KEY (`a`) /*T![clustered_index] NONCLUSTERED */\n) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"
 	c.Assert(createSQL, Equals, expected)
 
 	// Change / modify column should preserve index options.
@@ -1588,7 +1588,7 @@ func (s *testIntegrationSuite3) TestAlterColumn(c *C) {
 	tk.MustExec("alter table mc modify column c bigint") // Unique should be preserved
 	result = tk.MustQuery("show create table mc")
 	createSQL = result.Rows()[0][1]
-	expected = "CREATE TABLE `mc` (\n  `a` bigint(20) NOT NULL,\n  `b` bigint(20) DEFAULT NULL,\n  `c` bigint(20) DEFAULT NULL,\n  PRIMARY KEY (`a`),\n  UNIQUE KEY `c` (`c`)\n) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"
+	expected = "CREATE TABLE `mc` (\n  `a` bigint(20) NOT NULL,\n  `b` bigint(20) DEFAULT NULL,\n  `c` bigint(20) DEFAULT NULL,\n  PRIMARY KEY (`a`) /*T![clustered_index] NONCLUSTERED */,\n  UNIQUE KEY `c` (`c`)\n) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"
 	c.Assert(createSQL, Equals, expected)
 
 	// Dropping or keeping auto_increment is allowed, however adding is not allowed.
@@ -1597,15 +1597,15 @@ func (s *testIntegrationSuite3) TestAlterColumn(c *C) {
 	tk.MustExec("alter table mc modify column a bigint auto_increment") // Keeps auto_increment
 	result = tk.MustQuery("show create table mc")
 	createSQL = result.Rows()[0][1]
-	expected = "CREATE TABLE `mc` (\n  `a` bigint(20) NOT NULL AUTO_INCREMENT,\n  `b` int(11) DEFAULT NULL,\n  PRIMARY KEY (`a`)\n) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"
+	expected = "CREATE TABLE `mc` (\n  `a` bigint(20) NOT NULL AUTO_INCREMENT,\n  `b` int(11) DEFAULT NULL,\n  PRIMARY KEY (`a`) /*T![clustered_index] NONCLUSTERED */\n) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"
 	c.Assert(createSQL, Equals, expected)
 	_, err = tk.Exec("alter table mc modify column a bigint") // Droppping auto_increment is not allow when @@tidb_allow_remove_auto_inc == 'off'
 	c.Assert(err, NotNil)
 	tk.MustExec("set @@tidb_allow_remove_auto_inc = on")
 	tk.MustExec("alter table mc modify column a bigint") // Dropping auto_increment is ok when @@tidb_allow_remove_auto_inc == 'on'
 	result = tk.MustQuery("show create table mc")
 	createSQL = result.Rows()[0][1]
-	expected = "CREATE TABLE `mc` (\n  `a` bigint(20) NOT NULL,\n  `b` int(11) DEFAULT NULL,\n  PRIMARY KEY (`a`)\n) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"
+	expected = "CREATE TABLE `mc` (\n  `a` bigint(20) NOT NULL,\n  `b` int(11) DEFAULT NULL,\n  PRIMARY KEY (`a`) /*T![clustered_index] NONCLUSTERED */\n) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"
 	c.Assert(createSQL, Equals, expected)
 
 	_, err = tk.Exec("alter table mc modify column a bigint auto_increment") // Adds auto_increment should throw error
@@ -2639,8 +2639,8 @@ func (s *testIntegrationSuite7) TestDuplicateErrorMessage(c *C) {
 			config.UpdateGlobal(func(conf *config.Config) {
 				conf.EnableGlobalIndex = globalIndex
 			})
-			for _, clusteredIndex := range []int{0, 1} {
-				tk.MustExec(fmt.Sprintf("set session tidb_enable_clustered_index=%d;", clusteredIndex))
+			for _, clusteredIndex := range []bool{false, true} {
+				tk.Se.GetSessionVars().EnableClusteredIndex = clusteredIndex
 				for _, t := range tests {
 					tk.MustExec("drop table if exists t;")
 					fields := make([]string, len(t.types))

ddl/db_test.go

@@ -180,7 +180,7 @@ func (s *testSerialDBSuite) TestAddIndexWithPK(c *C) {
 	})
 
 	testAddIndexWithPK(tk, s, c)
-	tk.MustExec("set @@tidb_enable_clustered_index = 1;")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 	testAddIndexWithPK(tk, s, c)
 }
 
@@ -1058,7 +1058,7 @@ func (s *testDBSuite6) TestAddMultiColumnsIndexClusterIndex(c *C) {
 	tk.MustExec("create database test_add_multi_col_index_clustered;")
 	tk.MustExec("use test_add_multi_col_index_clustered;")
 
-	tk.MustExec("set @@tidb_enable_clustered_index = 1")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 	tk.MustExec("create table t (a int, b varchar(10), c int, primary key (a, b));")
 	tk.MustExec("insert into t values (1, '1', 1), (2, '2', NULL), (3, '3', 3);")
 	tk.MustExec("create index idx on t (a, c);")
@@ -1158,7 +1158,7 @@ func testAddIndex(c *C, store kv.Storage, lease time.Duration, tp testAddIndexTy
 	case testPartition:
 		tk.MustExec("set @@session.tidb_enable_table_partition = '1';")
 	case testClusteredIndex:
-		tk.MustExec("set @@tidb_enable_clustered_index = 1")
+		tk.Se.GetSessionVars().EnableClusteredIndex = true
 	}
 	tk.MustExec("drop table if exists test_add_index")
 	tk.MustExec(createTableSQL)
@@ -1794,7 +1794,7 @@ func (s *testDBSuite5) TestAlterPrimaryKey(c *C) {
 		"  `a` int(11) NOT NULL,\n"+
 		"  `b` int(11) NOT NULL,\n"+
 		"  KEY `idx` (`a`),\n"+
-		"  PRIMARY KEY (`a`,`b`)\n"+
+		"  PRIMARY KEY (`a`,`b`) /*T![clustered_index] NONCLUSTERED */\n"+
 		") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin"))
 	tk.MustExec("alter table test_add_pk2 drop primary key")
 	tk.MustQuery("desc test_add_pk2").Check(testutil.RowsWithSep(",", ""+
@@ -2794,7 +2794,7 @@ func (s *testSerialDBSuite) TestRepairTable(c *C) {
 
 	// Exec the show create table statement to make sure new tableInfo has been set.
 	result := tk.MustQuery("show create table origin")
-	c.Assert(result.Rows()[0][1], Equals, "CREATE TABLE `origin` (\n  `a` int(11) NOT NULL AUTO_INCREMENT,\n  `b` varchar(5) DEFAULT NULL,\n  `c` int(11) DEFAULT NULL,\n  PRIMARY KEY (`a`)\n) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin")
+	c.Assert(result.Rows()[0][1], Equals, "CREATE TABLE `origin` (\n  `a` int(11) NOT NULL AUTO_INCREMENT,\n  `b` varchar(5) DEFAULT NULL,\n  `c` int(11) DEFAULT NULL,\n  PRIMARY KEY (`a`) /*T![clustered_index] NONCLUSTERED */\n) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin")
 
 }
 
@@ -4529,7 +4529,7 @@ func (s *testSerialDBSuite) TestAddIndexForGeneratedColumn(c *C) {
 	})
 
 	testAddIndexForGeneratedColumn(tk, s, c)
-	tk.MustExec("set @@tidb_enable_clustered_index = 1;")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 	testAddIndexForGeneratedColumn(tk, s, c)
 }
 

ddl/ddl_api.go

@@ -628,7 +628,8 @@ func columnDefToCol(ctx sessionctx.Context, offset int, colDef *ast.ColumnDef, o
 			case ast.ColumnOptionPrimaryKey:
 				// Check PriKeyFlag first to avoid extra duplicate constraints.
 				if col.Flag&mysql.PriKeyFlag == 0 {
-					constraint := &ast.Constraint{Tp: ast.ConstraintPrimaryKey, Keys: keys}
+					constraint := &ast.Constraint{Tp: ast.ConstraintPrimaryKey, Keys: keys,
+						Option: &ast.IndexOption{PrimaryKeyTp: v.PrimaryKeyTp}}
 					constraints = append(constraints, constraint)
 					col.Flag |= mysql.PriKeyFlag
 					// Add NotNullFlag early so that processColumnFlags() can see it.
@@ -1424,23 +1425,35 @@ func buildTableInfo(
 			if err != nil {
 				return nil, err
 			}
-			if !config.GetGlobalConfig().AlterPrimaryKey {
-				singleIntPK := isSingleIntPK(constr, lastCol)
-				clusteredIdx := ctx.GetSessionVars().EnableClusteredIndex
-				if singleIntPK || clusteredIdx {
-					// Primary key cannot be invisible.
-					if constr.Option != nil && constr.Option.Visibility == ast.IndexVisibilityInvisible {
-						return nil, ErrPKIndexCantBeInvisible
-					}
-				}
-				if singleIntPK {
+			pkTp := model.PrimaryKeyTypeDefault
+			if constr.Option != nil {
+				pkTp = constr.Option.PrimaryKeyTp
+			}
+			switch pkTp {
+			case model.PrimaryKeyTypeNonClustered:
+				break
+			case model.PrimaryKeyTypeClustered:
+				if isSingleIntPK(constr, lastCol) {
 					tbInfo.PKIsHandle = true
-					// Avoid creating index for PK handle column.
-					continue
-				}
-				if clusteredIdx {
+				} else {
 					tbInfo.IsCommonHandle = true
 				}
+			case model.PrimaryKeyTypeDefault:
+				alterPKConf := config.GetGlobalConfig().AlterPrimaryKey
+				if isSingleIntPK(constr, lastCol) {
+					tbInfo.PKIsHandle = !alterPKConf
+				} else {
+					tbInfo.IsCommonHandle = !alterPKConf && ctx.GetSessionVars().EnableClusteredIndex
+				}
+			}
+			if tbInfo.PKIsHandle || tbInfo.IsCommonHandle {
+				// Primary key cannot be invisible.
+				if constr.Option != nil && constr.Option.Visibility == ast.IndexVisibilityInvisible {
+					return nil, ErrPKIndexCantBeInvisible
+				}
+			}
+			if tbInfo.PKIsHandle {
+				continue
 			}
 		}
 

ddl/failtest/fail_db_test.go

@@ -351,7 +351,7 @@ func (s *testFailDBSuite) TestAddIndexWorkerNum(c *C) {
 	tk.MustExec("use test_db")
 	tk.MustExec("drop table if exists test_add_index")
 	if s.IsCommonHandle {
-		tk.MustExec("set @@tidb_enable_clustered_index = 1")
+		tk.Se.GetSessionVars().EnableClusteredIndex = true
 		tk.MustExec("create table test_add_index (c1 bigint, c2 bigint, c3 bigint, primary key(c1, c3))")
 	} else {
 		tk.MustExec("create table test_add_index (c1 bigint, c2 bigint, c3 bigint, primary key(c1))")
@@ -485,7 +485,7 @@ func (s *testFailDBSuite) TestModifyColumn(c *C) {
 		"  `bb` mediumint(9) DEFAULT NULL,\n" +
 		"  `a` int(11) NOT NULL DEFAULT '1',\n" +
 		"  `c` int(11) NOT NULL DEFAULT '0',\n" +
-		"  PRIMARY KEY (`c`),\n" +
+		"  PRIMARY KEY (`c`) /*T![clustered_index] CLUSTERED */,\n" +
 		"  KEY `idx` (`bb`),\n" +
 		"  KEY `idx1` (`a`),\n" +
 		"  KEY `idx2` (`bb`,`c`)\n" +
@@ -499,7 +499,7 @@ func (s *testFailDBSuite) TestModifyColumn(c *C) {
 		"  `bb` mediumint(9) DEFAULT NULL,\n" +
 		"  `c` int(11) NOT NULL DEFAULT '0',\n" +
 		"  `aa` mediumint(9) DEFAULT NULL,\n" +
-		"  PRIMARY KEY (`c`),\n" +
+		"  PRIMARY KEY (`c`) /*T![clustered_index] CLUSTERED */,\n" +
 		"  KEY `idx` (`bb`),\n" +
 		"  KEY `idx1` (`aa`),\n" +
 		"  KEY `idx2` (`bb`,`c`)\n" +

ddl/serial_test.go

@@ -113,7 +113,7 @@ func (s *testSerialSuite) TestChangeMaxIndexLength(c *C) {
 func (s *testSerialSuite) TestPrimaryKey(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test")
-	tk.MustExec("set @@tidb_enable_clustered_index = 0")
+	tk.Se.GetSessionVars().EnableClusteredIndex = false
 
 	tk.MustExec("create table primary_key_test (a int, b varchar(10))")
 	tk.MustExec("create table primary_key_test_1 (a int, b varchar(10), primary key(a))")
@@ -174,7 +174,7 @@ func (s *testSerialSuite) TestPrimaryKey(c *C) {
 		conf.AlterPrimaryKey = false
 	})
 	tk.MustExec("drop table if exists t;")
-	tk.MustExec("set tidb_enable_clustered_index=1")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 	tk.MustExec("create table t(a int, b varchar(64), primary key(b));")
 	tk.MustExec("insert into t values(1,'a'), (2, 'b');")
 	config.UpdateGlobal(func(conf *config.Config) {
@@ -332,7 +332,7 @@ func (s *testSerialSuite) TestMultiRegionGetTableEndCommonHandle(c *C) {
 	tk.MustExec("drop database if exists test_get_endhandle")
 	tk.MustExec("create database test_get_endhandle")
 	tk.MustExec("use test_get_endhandle")
-	tk.MustExec("set @@tidb_enable_clustered_index = true")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 
 	tk.MustExec("create table t(a varchar(20), b int, c float, d bigint, primary key (a, b, c))")
 	var builder strings.Builder
@@ -376,7 +376,7 @@ func (s *testSerialSuite) TestGetTableEndCommonHandle(c *C) {
 	tk.MustExec("drop database if exists test_get_endhandle")
 	tk.MustExec("create database test_get_endhandle")
 	tk.MustExec("use test_get_endhandle")
-	tk.MustExec("set @@tidb_enable_clustered_index = true")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 
 	tk.MustExec("create table t(a varchar(15), b bigint, c int, primary key (a, b))")
 	tk.MustExec("create table t1(a varchar(15), b bigint, c int, primary key (a(2), b))")

domain/global_vars_cache.go

@@ -39,7 +39,8 @@ type GlobalVariableCache struct {
 	SingleFight singleflight.Group
 }
 
-const globalVariableCacheExpiry = 2 * time.Second
+// GlobalVariableCacheExpiry is the global variable cache TTL.
+const GlobalVariableCacheExpiry = 2 * time.Second
 
 // Update updates the global variable cache.
 func (gvc *GlobalVariableCache) Update(rows []chunk.Row, fields []*ast.ResultField) {
@@ -56,7 +57,7 @@ func (gvc *GlobalVariableCache) Update(rows []chunk.Row, fields []*ast.ResultFie
 func (gvc *GlobalVariableCache) Get() (succ bool, rows []chunk.Row, fields []*ast.ResultField) {
 	gvc.RLock()
 	defer gvc.RUnlock()
-	if time.Since(gvc.lastModify) < globalVariableCacheExpiry {
+	if time.Since(gvc.lastModify) < GlobalVariableCacheExpiry {
 		succ, rows, fields = !gvc.disable, gvc.rows, gvc.fields
 		return
 	}

executor/admin_test.go

@@ -194,7 +194,7 @@ func (s *testSuite5) TestClusteredIndexAdminRecoverIndex(c *C) {
 	tk.MustExec("drop database if exists test_cluster_index_admin_recover;")
 	tk.MustExec("create database test_cluster_index_admin_recover;")
 	tk.MustExec("use test_cluster_index_admin_recover;")
-	tk.MustExec("set tidb_enable_clustered_index=1;")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 	dbName := model.NewCIStr("test_cluster_index_admin_recover")
 	tblName := model.NewCIStr("t")
 
@@ -310,7 +310,7 @@ func (s *testSuite5) TestAdminRecoverIndex1(c *C) {
 	sc := s.ctx.GetSessionVars().StmtCtx
 	tk.MustExec("use test")
 	tk.MustExec("drop table if exists admin_test")
-	tk.MustExec("set @@tidb_enable_clustered_index=0;")
+	tk.Se.GetSessionVars().EnableClusteredIndex = false
 	tk.MustExec("create table admin_test (c1 varchar(255), c2 int, c3 int default 1, primary key(c1), unique key(c2))")
 	tk.MustExec("insert admin_test (c1, c2) values ('1', 1), ('2', 2), ('3', 3), ('10', 10), ('20', 20)")
 
@@ -515,7 +515,7 @@ func (s *testSuite5) TestAdminCleanupIndexPKNotHandle(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test")
 	tk.MustExec("drop table if exists admin_test")
-	tk.MustExec("set @@tidb_enable_clustered_index=0;")
+	tk.Se.GetSessionVars().EnableClusteredIndex = false
 	tk.MustExec("create table admin_test (c1 int, c2 int, c3 int, primary key (c1, c2))")
 	tk.MustExec("insert admin_test (c1, c2) values (1, 2), (3, 4), (-5, 5)")
 
@@ -627,7 +627,7 @@ func (s *testSuite5) TestClusteredAdminCleanupIndex(c *C) {
 	tk := testkit.NewTestKit(c, s.store)
 	tk.MustExec("use test")
 	tk.MustExec("drop table if exists admin_test")
-	tk.MustExec("set tidb_enable_clustered_index=1")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 	tk.MustExec("create table admin_test (c1 varchar(255), c2 int, c3 char(10) default 'c3', primary key (c1, c3), unique key(c2), key (c3))")
 	tk.MustExec("insert admin_test (c1, c2) values ('c1_1', 2), ('c1_2', 4), ('c1_3', NULL)")
 	tk.MustExec("insert admin_test (c1, c3) values ('c1_4', 'c3_4'), ('c1_5', 'c3_5'), ('c1_6', default)")

executor/aggregate_test.go

@@ -898,7 +898,7 @@ func (s *testSuiteAgg) TestAggEliminator(c *C) {
 func (s *testSuiteAgg) TestClusterIndexMaxMinEliminator(c *C) {
 	tk := testkit.NewTestKitWithInit(c, s.store)
 	tk.MustExec("drop table if exists t;")
-	tk.MustExec("set @@tidb_enable_clustered_index=1;")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 	tk.MustExec("create table t (a int, b int, c int, primary key(a, b));")
 	for i := 0; i < 10+1; i++ {
 		tk.MustExec("insert into t values (?, ?, ?)", i, i, i)

executor/analyze_test.go

@@ -129,7 +129,7 @@ func (s *testSuite1) TestClusterIndexAnalyze(c *C) {
 	tk.MustExec("drop database if exists test_cluster_index_analyze;")
 	tk.MustExec("create database test_cluster_index_analyze;")
 	tk.MustExec("use test_cluster_index_analyze;")
-	tk.MustExec("set @@tidb_enable_clustered_index=1;")
+	tk.Se.GetSessionVars().EnableClusteredIndex = true
 
 	tk.MustExec("create table t (a int, b int, c int, primary key(a, b));")
 	for i := 0; i < 100; i++ {

executor/batch_point_get_test.go

@@ -177,7 +177,7 @@ func (s *testBatchPointGetSuite) TestBatchPointGetLockExistKey(c *C) {
 
 		errCh <- tk1.ExecToErr("use test")
 		errCh <- tk2.ExecToErr("use test")
-		errCh <- tk1.ExecToErr("set session tidb_enable_clustered_index = 0")
+		tk1.Se.GetSessionVars().EnableClusteredIndex = false
 
 		errCh <- tk1.ExecToErr(fmt.Sprintf("drop table if exists %s", tableName))
 		errCh <- tk1.ExecToErr(fmt.Sprintf("create table %s(id int, v int, k int, %s key0(id, v))", tableName, key))