ttl,ddl: disable ttl for fk and temp table

ddl/ddl_api.go

@@ -2116,7 +2116,7 @@ func checkTableInfoValidWithStmt(ctx sessionctx.Context, tbInfo *model.TableInfo
 		}
 	}
 	if tbInfo.TTLInfo != nil {
-		if err := checkTTLInfoValid(ctx, tbInfo); err != nil {
+		if err := checkTTLInfoValid(ctx, s.Table.Schema, tbInfo); err != nil {
 			return errors.Trace(err)
 		}
 	}
@@ -5368,7 +5368,7 @@ func (d *ddl) AlterTableTTLInfoOrEnable(ctx sessionctx.Context, ident ast.Ident,
 	var job *model.Job
 	if ttlInfo != nil {
 		tblInfo.TTLInfo = ttlInfo
-		err = checkTTLInfoValid(ctx, tblInfo)
+		err = checkTTLInfoValid(ctx, ident.Schema, tblInfo)
 		if err != nil {
 			return err
 		}

ddl/foreign_key.go

@@ -263,6 +263,9 @@ func checkTableForeignKey(referTblInfo, tblInfo *model.TableInfo, fkInfo *model.
 	if referTblInfo.TempTableType != model.TempTableNone || tblInfo.TempTableType != model.TempTableNone {
 		return infoschema.ErrCannotAddForeign
 	}
+	if referTblInfo.TTLInfo != nil {
+		return dbterror.ErrUnsupportedTTLReferencedByFK
+	}
 
 	// check refer columns in parent table.
 	for i := range fkInfo.RefCols {

ddl/ttl.go

@@ -26,6 +26,7 @@ import (
 	"github.com/pingcap/tidb/parser/format"
 	"github.com/pingcap/tidb/parser/model"
 	"github.com/pingcap/tidb/sessionctx"
+	"github.com/pingcap/tidb/sessiontxn"
 	"github.com/pingcap/tidb/types"
 	"github.com/pingcap/tidb/util/dbterror"
 )
@@ -83,11 +84,15 @@ func onTTLInfoChange(d *ddlCtx, t *meta.Meta, job *model.Job) (ver int64, err er
 	return ver, nil
 }
 
-func checkTTLInfoValid(ctx sessionctx.Context, tblInfo *model.TableInfo) error {
+func checkTTLInfoValid(ctx sessionctx.Context, schema model.CIStr, tblInfo *model.TableInfo) error {
 	if err := checkTTLIntervalExpr(ctx, tblInfo.TTLInfo); err != nil {
 		return err
 	}
 
+	if err := checkTTLTableSuitable(ctx, schema, tblInfo); err != nil {
+		return err
+	}
+
 	return checkTTLInfoColumnType(tblInfo)
 }
 
@@ -119,6 +124,22 @@ func checkTTLInfoColumnType(tblInfo *model.TableInfo) error {
 	return nil
 }
 
+// checkTTLTableSuitable returns whether this table is suitable to be a TTL table
+// A temporary table or a parent table referenced by a foreign key cannot be TTL table
+func checkTTLTableSuitable(ctx sessionctx.Context, schema model.CIStr, tblInfo *model.TableInfo) error {
+	if tblInfo.TempTableType != model.TempTableNone {
+		return dbterror.ErrTempTableNotAllowedWithTTL
+	}
+
+	// checks even when the foreign key check is not enabled, to keep safe
+	is := sessiontxn.GetTxnManager(ctx).GetTxnInfoSchema()
+	if referredFK := checkTableHasForeignKeyReferred(is, schema.L, tblInfo.Name.L, nil, true); referredFK != nil {
+		return dbterror.ErrUnsupportedTTLReferencedByFK
+	}
+
+	return nil
+}
+
 func checkDropColumnWithTTLConfig(tblInfo *model.TableInfo, colName string) error {
 	if tblInfo.TTLInfo != nil {
 		if tblInfo.TTLInfo.ColumnName.L == colName {

errno/errcode.go

@@ -1039,6 +1039,8 @@ const (
 	ErrUnsupportedColumnInTTLConfig        = 8148
 	ErrTTLColumnCannotDrop                 = 8149
 	ErrSetTTLEnableForNonTTLTable          = 8150
+	ErrTempTableNotAllowedWithTTL          = 8151
+	ErrUnsupportedTTLReferencedByFK        = 8152
 
 	// Error codes used by TiDB ddl package
 	ErrUnsupportedDDLOperation            = 8200

errno/errname.go

@@ -1034,6 +1034,8 @@ var MySQLErrName = map[uint16]*mysql.ErrMessage{
 	ErrUnsupportedColumnInTTLConfig:  mysql.Message("Field '%-.192s' is of a not supported type for TTL config, expect DATETIME, DATE or TIMESTAMP", nil),
 	ErrTTLColumnCannotDrop:           mysql.Message("Cannot drop column '%-.192s': needed in TTL config", nil),
 	ErrSetTTLEnableForNonTTLTable:    mysql.Message("Cannot set TTL_ENABLE on a table without TTL config", nil),
+	ErrTempTableNotAllowedWithTTL:    mysql.Message("Set TTL for temporary table is not allowed", nil),
+	ErrUnsupportedTTLReferencedByFK:  mysql.Message("Set TTL for a table referenced by foreign key is not allowed", nil),
 
 	ErrWarnOptimizerHintInvalidInteger:  mysql.Message("integer value is out of range in '%s'", nil),
 	ErrWarnOptimizerHintUnsupportedHint: mysql.Message("Optimizer hint %s is not supported by TiDB and is ignored", nil),

errors.toml

@@ -1216,6 +1216,16 @@ error = '''
 Cannot set TTL_ENABLE on a table without TTL config
 '''
 
+["ddl:8151"]
+error = '''
+Set TTL for temporary table is not allowed
+'''
+
+["ddl:8152"]
+error = '''
+Set TTL for a table referenced by foreign key is not allowed
+'''
+
 ["ddl:8200"]
 error = '''
 Unsupported shard_row_id_bits for table with primary key as row id

executor/ddl_test.go

@@ -1582,3 +1582,39 @@ func TestAlterTTLInfo(t *testing.T) {
 
 	tk.MustGetErrMsg("ALTER TABLE t TTL_ENABLE = 'OFF'", "[ddl:8150]Cannot set TTL_ENABLE on a table without TTL config")
 }
+
+func TestDisableTTLForTempTable(t *testing.T) {
+	parser.TTLFeatureGate = true
+
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+
+	tk.MustGetDBError("CREATE TEMPORARY TABLE t (created_at datetime) TTL = `created_at` + INTERVAL 5 DAY", dbterror.ErrTempTableNotAllowedWithTTL)
+}
+
+func TestDisableTTLForFKParentTable(t *testing.T) {
+	parser.TTLFeatureGate = true
+
+	store := testkit.CreateMockStore(t)
+	tk := testkit.NewTestKit(t, store)
+	tk.MustExec("use test")
+
+	// alter ttl for a FK parent table is not allowed
+	tk.MustExec("set global tidb_enable_foreign_key='ON'")
+	tk.MustExec("CREATE TABLE t (id int primary key, created_at datetime)")
+	tk.MustExec("CREATE TABLE t_1 (t_id int, foreign key fk_t_id(t_id) references t(id))")
+	tk.MustGetDBError("ALTER TABLE t TTL = created_at + INTERVAL 5 YEAR", dbterror.ErrUnsupportedTTLReferencedByFK)
+	tk.MustExec("drop table t,t_1")
+
+	// refuse to reference TTL key when create table
+	tk.MustExec("CREATE TABLE t (id int primary key, created_at datetime) TTL = created_at + INTERVAL 5 YEAR")
+	tk.MustGetDBError("CREATE TABLE t_1 (t_id int, foreign key fk_t_id(t_id) references t(id))", dbterror.ErrUnsupportedTTLReferencedByFK)
+	tk.MustExec("drop table t")
+
+	// refuse to add foreign key reference TTL table
+	tk.MustExec("CREATE TABLE t (id int primary key, created_at datetime) TTL = created_at + INTERVAL 5 YEAR")
+	tk.MustExec("CREATE TABLE t_1 (t_id int)")
+	tk.MustGetDBError("ALTER TABLE t_1 ADD FOREIGN KEY fk_t_id(t_id) references t(id)", dbterror.ErrUnsupportedTTLReferencedByFK)
+	tk.MustExec("drop table t,t_1")
+}

util/dbterror/ddl_terror.go

@@ -425,4 +425,8 @@ var (
 	ErrTTLColumnCannotDrop = ClassDDL.NewStd(mysql.ErrTTLColumnCannotDrop)
 	// ErrSetTTLEnableForNonTTLTable returns when the `TTL_ENABLE` option is set on a non-TTL table
 	ErrSetTTLEnableForNonTTLTable = ClassDDL.NewStd(mysql.ErrSetTTLEnableForNonTTLTable)
+	// ErrTempTableNotAllowedWithTTL returns when setting TTL config for a temp table
+	ErrTempTableNotAllowedWithTTL = ClassDDL.NewStd(mysql.ErrTempTableNotAllowedWithTTL)
+	// ErrUnsupportedTTLReferencedByFK returns when the TTL config is set for a table referenced by foreign key
+	ErrUnsupportedTTLReferencedByFK = ClassDDL.NewStd(mysql.ErrUnsupportedTTLReferencedByFK)
 )