ddl: reject alter auto_random_base on a non auto_random table (#17714) (

#17827)

* cherry pick #17714 to release-3.1

Signed-off-by: sre-bot <sre-bot@pingcap.com>

* resolve conflicts

Co-authored-by: tangenta <tangenta@126.com>
Co-authored-by: Arenatlx <ailinsilence4@gmail.com>
Co-authored-by: ti-srebot <66930949+ti-srebot@users.noreply.github.com>

ddl/ddl_api.go

@@ -2150,20 +2150,27 @@ func (d *ddl) RebaseAutoID(ctx sessionctx.Context, ident ast.Ident, newBase int6
 	if err != nil {
 		return errors.Trace(err)
 	}
-	autoIncID, err := t.Allocator(ctx, tp).NextGlobalAutoID(t.Meta().ID)
+	var actionType model.ActionType
+	switch tp {
+	case autoid.AutoRandomType:
+		if t.Meta().AutoRandomBits == 0 {
+			return errors.Trace(ErrInvalidAutoRandom.GenWithStackByArgs(autoid.AutoRandomRebaseNotApplicable))
+		}
+		actionType = model.ActionRebaseAutoRandomBase
+	case autoid.RowIDAllocType:
+		actionType = model.ActionRebaseAutoID
+	}
+
+	autoID, err := t.Allocator(ctx, tp).NextGlobalAutoID(t.Meta().ID)
 	if err != nil {
 		return errors.Trace(err)
 	}
-	// If newBase < autoIncID, we need to do a rebase before returning.
+	// If newBase < autoID, we need to do a rebase before returning.
 	// Assume there are 2 TiDB servers: TiDB-A with allocator range of 0 ~ 30000; TiDB-B with allocator range of 30001 ~ 60000.
 	// If the user sends SQL `alter table t1 auto_increment = 100` to TiDB-B,
 	// and TiDB-B finds 100 < 30001 but returns without any handling,
 	// then TiDB-A may still allocate 99 for auto_increment column. This doesn't make sense for the user.
-	newBase = mathutil.MaxInt64(newBase, autoIncID)
-	actionType := model.ActionRebaseAutoID
-	if tp == autoid.AutoRandomType {
-		actionType = model.ActionRebaseAutoRandomBase
-	}
+	newBase = mathutil.MaxInt64(newBase, autoID)
 	job := &model.Job{
 		SchemaID:   schema.ID,
 		TableID:    t.Meta().ID,

executor/ddl_test.go

@@ -1001,6 +1001,12 @@ func (s *testAutoRandomSuite) TestAutoRandomTableOption(c *C) {
 		c.Assert(orderedHandles[i], Equals, i+3000000)
 	}
 	tk.MustExec("drop table alter_table_auto_random_option")
+
+	// Alter auto_random_base on non auto_random table.
+	tk.MustExec("create table alter_auto_random_normal (a int)")
+	_, err = tk.Exec("alter table alter_auto_random_normal auto_random_base = 100")
+	c.Assert(err, NotNil)
+	c.Assert(strings.Contains(err.Error(), autoid.AutoRandomRebaseNotApplicable), IsTrue, Commentf(err.Error()))
 }
 
 // Test filter different kind of allocators.

meta/autoid/errors.go

@@ -64,4 +64,6 @@ const (
 	AutoRandomExplicitInsertDisabledErrMsg = "Explicit insertion on auto_random column is disabled. Try to set @@allow_auto_random_explicit_insert = true."
 	// AutoRandomOnNonBigIntColumn is reported when define auto random to non bigint column
 	AutoRandomOnNonBigIntColumn = "auto_random option must be defined on `bigint` column, but not on `%s` column"
+	// AutoRandomRebaseNotApplicable is reported when alter auto_random base on a non auto_random table.
+	AutoRandomRebaseNotApplicable = "alter auto_random_base of a non auto_random table"
 )