Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

executor: resolve errors caused by in null in point/batch ... #18848

Merged
merged 4 commits into from
Jul 29, 2020
Merged
Show file tree
Hide file tree
Changes from 3 commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 4 additions & 1 deletion executor/batch_point_get.go
Original file line number Diff line number Diff line change
Expand Up @@ -150,7 +150,10 @@ func (e *BatchPointGetExec) initialize(ctx context.Context) error {
keys := make([]kv.Key, 0, len(e.idxVals))
for _, idxVals := range e.idxVals {
physID := getPhysID(e.tblInfo, idxVals[e.partPos].GetInt64())
idxKey, err1 := encodeIndexKey(e.base(), e.tblInfo, e.idxInfo, idxVals, physID)
idxKey, hasNull, err1 := encodeIndexKey(e.base(), e.tblInfo, e.idxInfo, idxVals, physID)
if hasNull {
continue
}
if err1 != nil && !kv.ErrNotExist.Equal(err1) {
return err1
}
Expand Down
20 changes: 14 additions & 6 deletions executor/point_get.go
Original file line number Diff line number Diff line change
Expand Up @@ -157,7 +157,11 @@ func (e *PointGetExecutor) Next(ctx context.Context, req *chunk.Chunk) error {
tblID = e.tblInfo.ID
}
if e.idxInfo != nil {
e.idxKey, err = encodeIndexKey(e.base(), e.tblInfo, e.idxInfo, e.idxVals, tblID)
hasNull := false
e.idxKey, hasNull, err = encodeIndexKey(e.base(), e.tblInfo, e.idxInfo, e.idxVals, tblID)
if hasNull {
return nil
}
if err != nil && !kv.ErrNotExist.Equal(err) {
return err
}
Expand Down Expand Up @@ -299,9 +303,13 @@ func (e *PointGetExecutor) get(ctx context.Context, key kv.Key) ([]byte, error)
return e.snapshot.Get(ctx, key)
}

func encodeIndexKey(e *baseExecutor, tblInfo *model.TableInfo, idxInfo *model.IndexInfo, idxVals []types.Datum, tID int64) (_ []byte, err error) {
func encodeIndexKey(e *baseExecutor, tblInfo *model.TableInfo, idxInfo *model.IndexInfo, idxVals []types.Datum, tID int64) (_ []byte, hasNull bool, err error) {
sc := e.ctx.GetSessionVars().StmtCtx
for i := range idxVals {
if idxVals[i].IsNull() {
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

If we skip the null value, we built a non exists index key, I think it is not the right way to fix the bug.

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Why does the index key not exist? This loop is used to cast the idxVals to target types, which is unnecessary for null type values.
After casting, all null values will also be encoded into the key.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

But if the index has a null value, it is not encoded as unique index, the rowid is appended to the key.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I mean we should let the caller know the index value has a null value, we can not point get this key.

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

okay

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Updated. PTAL @coocood

hasNull = true
continue
}
colInfo := tblInfo.Columns[idxInfo.Columns[i].Offset]
// table.CastValue will append 0x0 if the string value's length is smaller than the BINARY column's length.
// So we don't use CastValue for string value for now.
Expand All @@ -313,19 +321,19 @@ func encodeIndexKey(e *baseExecutor, tblInfo *model.TableInfo, idxInfo *model.In
} else {
idxVals[i], err = table.CastValue(e.ctx, idxVals[i], colInfo, true, false)
if types.ErrOverflow.Equal(err) {
return nil, kv.ErrNotExist
return nil, false, kv.ErrNotExist
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

We could return nil, true, nil, then outer do not need to check kv.ErrNotExist.

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

After discussing with @tiancaiamao , I change the argument nonExist to hasNull. PTAL

}
}
if err != nil {
return nil, err
return nil, false, err
}
}

encodedIdxVals, err := codec.EncodeKey(sc, nil, idxVals...)
if err != nil {
return nil, err
return nil, false, err
}
return tablecodec.EncodeIndexSeekKey(tID, idxInfo.ID, encodedIdxVals), nil
return tablecodec.EncodeIndexSeekKey(tID, idxInfo.ID, encodedIdxVals), hasNull, nil
}

func decodeRowValToChunk(e *baseExecutor, tblInfo *model.TableInfo, handle int64, rowVal []byte, chk *chunk.Chunk, rd *rowcodec.ChunkDecoder) error {
Expand Down
10 changes: 10 additions & 0 deletions executor/point_get_test.go
Original file line number Diff line number Diff line change
Expand Up @@ -512,6 +512,16 @@ func (s *testPointGetSuite) TestSelectCheckVisibility(c *C) {
checkSelectResultError("select * from t", tikv.ErrGCTooEarly)
}

func (s *testPointGetSuite) TestNullValues(c *C) {
tk := testkit.NewTestKit(c, s.store)
tk.MustExec("use test")
tk.MustExec("drop table if exists t")
tk.MustExec("create table t ( id bigint(10) primary key, f varchar(191) default null, unique key `idx_f` (`f`))")
tk.MustExec(`insert into t values (1, "")`)
rs := tk.MustQuery(`select * from t where f in (null)`).Rows()
c.Assert(len(rs), Equals, 0)
}

func (s *testPointGetSuite) TestReturnValues(c *C) {
tk := testkit.NewTestKit(c, s.store)
tk.MustExec("use test")
Expand Down