diff --git a/ddl/db_change_test.go b/ddl/db_change_test.go index 451dcf69b8089..1878377bacc21 100644 --- a/ddl/db_change_test.go +++ b/ddl/db_change_test.go @@ -754,6 +754,16 @@ func (s *testStateChangeSuite) TestParallelDropColumn(c *C) { s.testControlParallelExecSQL(c, sql, sql, f) } +func (s *testStateChangeSuite) TestParallelDropIndex(c *C) { + sql1 := "alter table t drop index idx1 ;" + sql2 := "alter table t drop index idx2 ;" + f := func(c *C, err1, err2 error) { + c.Assert(err1, IsNil) + c.Assert(err2.Error(), Equals, "[autoid:1075]Incorrect table definition; there can be only one auto column and it must be defined as a key") + } + s.testControlParallelExecSQL(c, sql1, sql2, f) +} + func (s *testStateChangeSuite) TestParallelCreateAndRename(c *C) { sql1 := "create table t_exists(c int);" sql2 := "alter table t rename to t_exists;" @@ -770,7 +780,7 @@ type checkRet func(c *C, err1, err2 error) func (s *testStateChangeSuite) testControlParallelExecSQL(c *C, sql1, sql2 string, f checkRet) { _, err := s.se.Execute(context.Background(), "use test_db_state") c.Assert(err, IsNil) - _, err = s.se.Execute(context.Background(), "create table t(a int, b int, c int)") + _, err = s.se.Execute(context.Background(), "create table t(a int, b int, c int, d int auto_increment,e int, index idx1(d), index idx2(d,e))") c.Assert(err, IsNil) defer s.se.Execute(context.Background(), "drop table t") diff --git a/ddl/ddl_api.go b/ddl/ddl_api.go index f0438941462f2..bdb3247c4a0b4 100644 --- a/ddl/ddl_api.go +++ b/ddl/ddl_api.go @@ -3236,11 +3236,10 @@ func (d *ddl) DropIndex(ctx sessionctx.Context, ti ast.Ident, indexName model.CI return ErrCantDropFieldOrKey.GenWithStack("index %s doesn't exist", indexName) } - cols := t.Cols() - for _, idxCol := range indexInfo.Columns { - if mysql.HasAutoIncrementFlag(cols[idxCol.Offset].Flag) { - return autoid.ErrWrongAutoKey - } + // Check for drop index on auto_increment column. + err = checkDropIndexOnAutoIncrementColumn(t.Meta(), indexInfo) + if err != nil { + return errors.Trace(err) } job := &model.Job{ diff --git a/ddl/index.go b/ddl/index.go index f79a0524a1b71..1c12f35ef5341 100644 --- a/ddl/index.go +++ b/ddl/index.go @@ -30,6 +30,7 @@ import ( "github.com/pingcap/tidb/infoschema" "github.com/pingcap/tidb/kv" "github.com/pingcap/tidb/meta" + "github.com/pingcap/tidb/meta/autoid" "github.com/pingcap/tidb/metrics" "github.com/pingcap/tidb/sessionctx" "github.com/pingcap/tidb/sessionctx/variable" @@ -465,9 +466,40 @@ func checkDropIndex(t *meta.Meta, job *model.Job) (*model.TableInfo, *model.Inde job.State = model.JobStateCancelled return nil, nil, ErrCantDropFieldOrKey.GenWithStack("index %s doesn't exist", indexName) } + + // Double check for drop index on auto_increment column. + err = checkDropIndexOnAutoIncrementColumn(tblInfo, indexInfo) + if err != nil { + job.State = model.JobStateCancelled + return nil, nil, autoid.ErrWrongAutoKey + } + return tblInfo, indexInfo, nil } +func checkDropIndexOnAutoIncrementColumn(tblInfo *model.TableInfo, indexInfo *model.IndexInfo) error { + cols := tblInfo.Columns + for _, idxCol := range indexInfo.Columns { + if !mysql.HasAutoIncrementFlag(cols[idxCol.Offset].Flag) { + continue + } + // check the count of index on auto_increment column. + count := 0 + for _, idx := range tblInfo.Indices { + for _, c := range idx.Columns { + if c.Name.L == idxCol.Name.L { + count++ + break + } + } + } + if count < 2 { + return autoid.ErrWrongAutoKey + } + } + return nil +} + func checkRenameIndex(t *meta.Meta, job *model.Job) (*model.TableInfo, model.CIStr, model.CIStr, error) { var from, to model.CIStr schemaID := job.SchemaID