diff --git a/ddl/ddl.go b/ddl/ddl.go
index 041e8e7610..3c155287b3 100644
--- a/ddl/ddl.go
+++ b/ddl/ddl.go
@@ -593,28 +593,6 @@ func (d *ddl) DropTable(ctx context.Context, ti table.Ident) (err error) {
 	return errors.Trace(err)
 }
 
-func (d *ddl) deleteTableData(ctx context.Context, t table.Table) error {
-	// Remove data.
-	err := t.Truncate(ctx)
-	if err != nil {
-		return errors.Trace(err)
-	}
-	txn, err := ctx.GetTxn(false)
-	if err != nil {
-		return errors.Trace(err)
-	}
-	// Remove indices.
-	for _, v := range t.Indices() {
-		if v != nil && v.X != nil {
-			if err = v.X.Drop(txn); err != nil {
-				return errors.Trace(err)
-			}
-		}
-	}
-
-	return nil
-}
-
 func (d *ddl) CreateIndex(ctx context.Context, ti table.Ident, unique bool, indexName model.CIStr, idxColNames []*coldef.IndexColName) error {
 	is := d.infoHandle.Get()
 	schema, ok := is.SchemaByName(ti.Schema)
diff --git a/ddl/ddl_test.go b/ddl/ddl_test.go
index 4f32bc642e..9382effb39 100644
--- a/ddl/ddl_test.go
+++ b/ddl/ddl_test.go
@@ -159,6 +159,14 @@ func (ts *testSuite) TestDDL(c *C) {
 	c.Assert(len(tbs), Equals, 2)
 	err = sessionctx.GetDomain(ctx).DDL().DropIndex(ctx, tbIdent, idxName)
 	c.Assert(err, IsNil)
+	alterStmt = statement("alter table t add index idx_c (c)").(*stmts.AlterTableStmt)
+	err = sessionctx.GetDomain(ctx).DDL().AlterTable(ctx, tbIdent, alterStmt.Specs)
+	alterStmt = statement("alter table t drop index idx_c").(*stmts.AlterTableStmt)
+	err = sessionctx.GetDomain(ctx).DDL().AlterTable(ctx, tbIdent, alterStmt.Specs)
+	alterStmt = statement("alter table t add unique index idx_c (c)").(*stmts.AlterTableStmt)
+	err = sessionctx.GetDomain(ctx).DDL().AlterTable(ctx, tbIdent, alterStmt.Specs)
+	alterStmt = statement("alter table t drop index idx_c").(*stmts.AlterTableStmt)
+	err = sessionctx.GetDomain(ctx).DDL().AlterTable(ctx, tbIdent, alterStmt.Specs)
 	err = sessionctx.GetDomain(ctx).DDL().DropTable(ctx, tbIdent)
 	c.Assert(err, IsNil)
 	tbs = sessionctx.GetDomain(ctx).InfoSchema().SchemaTables(tbIdent.Schema)
@@ -274,3 +282,7 @@ func statement(sql string) stmt.Statement {
 	stm, _ := compiler.Compile(lexer.Stmts()[0])
 	return stm
 }
+
+func init() {
+	log.SetLevelByString("error")
+}