// Next returns the next row of the sub result.
// If no more row to return, data would be nil.
func (pr *partialResult) Next() (handle int64, data []types.Datum, err error) {
if !pr.fetched {
select {
case err = <-pr.done:
}
pr.fetched = true
if err != nil {
return 0, nil, err
}
}
if pr.cursor >= len(pr.resp.Rows) {
return 0, nil, nil
}
row := pr.resp.Rows[pr.cursor]
data, err = tablecodec.DecodeValues(row.Data, pr.fields, pr.index)
if err != nil {
return 0, nil, errors.Trace(err)
}
if data == nil {
// When no column is referenced, the data may be nil, like 'select count(*) from t'.
// In this case, we need to create a zero length datum slice,
// as caller will check if data is nil to finish iteration.
data = make([]types.Datum, 0)
}
if !pr.aggregate {
handleBytes := row.GetHandle()
datums, err := codec.Decode(handleBytes)
if err != nil {
return 0, nil, errors.Trace(err)
}
handle = datums[0].GetInt64()
}
pr.cursor++
return
}
// Next returns current key and moves iterator to the next step.
func (c *indexIter) Next() (val []interface{}, h int64, err error) {
if !c.it.Valid() {
return nil, 0, errors.Trace(io.EOF)
}
if !c.it.Key().HasPrefix(c.prefix) {
return nil, 0, errors.Trace(io.EOF)
}
// get indexedValues
buf := c.it.Key()[len(c.prefix):]
vv, err := codec.Decode(buf)
if err != nil {
return nil, 0, errors.Trace(err)
}
// if index is *not* unique, the handle is in keybuf
if !c.idx.unique {
h = vv[len(vv)-1].(int64)
val = vv[0 : len(vv)-1]
} else {
// otherwise handle is value
h, err = decodeHandle(c.it.Value())
if err != nil {
return nil, 0, errors.Trace(err)
}
val = vv
}
// update new iter to next
err = c.it.Next()
if err != nil {
return nil, 0, errors.Trace(err)
}
return
}
func (e *Evaluator) decodeValueList(valueListExpr *tipb.Expr) (*decodedValueList, error) {
if len(valueListExpr.Val) == 0 {
// Empty value list.
return &decodedValueList{}, nil
}
if e.valueLists == nil {
e.valueLists = make(map[*tipb.Expr]*decodedValueList)
}
decoded := e.valueLists[valueListExpr]
if decoded != nil {
return decoded, nil
}
list, err := codec.Decode(valueListExpr.Val)
if err != nil {
return nil, errors.Trace(err)
}
var hasNull bool
for _, v := range list {
if v.IsNull() {
hasNull = true
}
}
decoded = &decodedValueList{values: list, hasNull: hasNull}
e.valueLists[valueListExpr] = decoded
return decoded, nil
}
// DecodeValue implements table.Table DecodeValue interface.
func DecodeValue(data []byte, tp *types.FieldType) (types.Datum, error) {
values, err := codec.Decode(data)
if err != nil {
return types.Datum{}, errors.Trace(err)
}
return unflatten(values[0], tp)
}
// DecodeRow decodes a byte slice into datums.
// TODO: We should only decode columns in the cols map.
// Row layout: colID1, value1, colID2, value2, .....
func DecodeRow(data []byte, cols map[int64]*types.FieldType) (map[int64]types.Datum, error) {
if data == nil {
return nil, nil
}
values, err := codec.Decode(data)
if err != nil {
return nil, errors.Trace(err)
}
if len(values)%2 != 0 {
return nil, errors.New("Decoded row value length is not even number!")
}
row := make(map[int64]types.Datum, len(cols))
for i := 0; i < len(values); i += 2 {
cid := values[i]
id := cid.GetInt64()
ft, ok := cols[id]
if ok {
v := values[i+1]
v, err = Unflatten(v, ft)
if err != nil {
return nil, errors.Trace(err)
}
row[id] = v
}
}
return row, nil
}
func decodeValue(data []byte, cols []*model.ColumnInfo) ([]interface{}, error) {
values, err := codec.Decode(data)
if err != nil {
return nil, errors.Trace(err)
}
if len(values) != len(cols) {
return nil, errors.Errorf("Column count does not match, expect %d, actual %d", len(cols), len(values))
}
var rvalues []interface{}
for i, col := range cols {
// TODO: support more types if we really need.
switch col.Tp {
case mysql.TypeString, mysql.TypeVarchar:
val := string(values[i].([]byte))
rvalues = append(rvalues, val)
case mysql.TypeEnum:
val, err := mysql.ParseEnumValue(col.Elems, values[i].(uint64))
if err != nil {
return nil, errors.Trace(err)
}
rvalues = append(rvalues, val.String())
}
}
return rvalues, nil
}
// DecodeValue implements table.Table DecodeValue interface.
func (t *Table) DecodeValue(data []byte, col *column.Col) (interface{}, error) {
values, err := codec.Decode(data)
if err != nil {
return nil, errors.Trace(err)
}
return t.unflatten(values[0], col)
}
// DecodeValues decodes a byte slice into datums with column types.
func DecodeValues(data []byte, fts []*types.FieldType) ([]types.Datum, error) {
values, err := codec.Decode(data)
if err != nil {
return nil, errors.Trace(err)
}
if len(values) > len(fts) {
return nil, errors.Errorf("invalid column count %d is less than value count %d", len(fts), len(values))
}
for i := range values {
values[i], err = unflatten(values[i], fts[i])
if err != nil {
return nil, errors.Trace(err)
}
}
return values, nil
}
func mutationRowsToRows(c *C, mutationRows [][]byte, firstColumn, secondColumn int) [][]types.Datum {
var rows [][]types.Datum
for _, mutationRow := range mutationRows {
datums, err := codec.Decode(mutationRow, 5)
c.Assert(err, IsNil)
for i := range datums {
if i != firstColumn && i != secondColumn {
// Column ID or handle
c.Assert(datums[i].GetInt64(), Greater, int64(0))
}
if datums[i].Kind() == types.KindBytes {
datums[i].SetBytesAsString(datums[i].GetBytes())
}
}
row := []types.Datum{datums[firstColumn], datums[secondColumn]}
rows = append(rows, row)
}
return rows
}
// Next returns the next row of the sub result.
// If no more row to return, data would be nil.
func (r *SubResult) Next() (handle int64, data []types.Datum, err error) {
if r.resp == nil {
r.resp = new(tipb.SelectResponse)
var b []byte
b, err = ioutil.ReadAll(r.reader)
r.reader.Close()
if err != nil {
return 0, nil, errors.Trace(err)
}
err = proto.Unmarshal(b, r.resp)
if err != nil {
return 0, nil, errors.Trace(err)
}
if r.resp.Error != nil {
return 0, nil, errInvalidResp.Gen("[%d %s]", r.resp.Error.GetCode(), r.resp.Error.GetMsg())
}
}
if r.cursor >= len(r.resp.Rows) {
return 0, nil, nil
}
row := r.resp.Rows[r.cursor]
data, err = tablecodec.DecodeValues(row.Data, r.fields, r.index)
if err != nil {
return 0, nil, errors.Trace(err)
}
if data == nil {
// When no column is referenced, the data may be nil, like 'select count(*) from t'.
// In this case, we need to create a zero length datum slice,
// as caller will check if data is nil to finish iteration.
data = make([]types.Datum, 0)
}
if !r.aggregate {
handleBytes := row.GetHandle()
datums, err := codec.Decode(handleBytes)
if err != nil {
return 0, nil, errors.Trace(err)
}
handle = datums[0].GetInt64()
}
r.cursor++
return
}
// DecodeValues decodes a byte slice into datums with column types.
func DecodeValues(data []byte, fts []*types.FieldType, inIndex bool) ([]types.Datum, error) {
if len(data) == 0 {
return nil, nil
}
values, err := codec.Decode(data, len(fts))
if err != nil {
return nil, errors.Trace(err)
}
if len(values) > len(fts) {
return nil, errInvalidColumnCount.Gen("invalid column count %d is less than value count %d", len(fts), len(values))
}
for i := range values {
values[i], err = Unflatten(values[i], fts[i], inIndex)
if err != nil {
return nil, errors.Trace(err)
}
}
return values, nil
}
// TableFromPB creates a table statistics from protobuffer.
func TableFromPB(ti *model.TableInfo, tpb *TablePB) (*Table, error) {
if tpb.GetId() != ti.ID {
return nil, errors.Errorf("table id not match, expected %d, got %d", ti.ID, tpb.GetId())
}
if len(tpb.Columns) != len(ti.Columns) {
return nil, errors.Errorf("column count not match, expected %d, got %d", len(ti.Columns), len(tpb.Columns))
}
for i := range ti.Columns {
if ti.Columns[i].ID != tpb.Columns[i].GetId() {
return nil, errors.Errorf("column ID not match, expected %d, got %d", ti.Columns[i].ID, tpb.Columns[i].GetId())
}
}
t := &Table{info: ti}
t.TS = tpb.GetTs()
t.Count = tpb.GetCount()
t.Columns = make([]*Column, len(tpb.GetColumns()))
for i, cInfo := range t.info.Columns {
cpb := tpb.Columns[i]
values, err := codec.Decode(cpb.GetValue())
if err != nil {
return nil, errors.Trace(err)
}
c := &Column{
ID: cpb.GetId(),
NDV: cpb.GetNdv(),
Numbers: cpb.GetNumbers(),
Values: make([]types.Datum, len(values)),
Repeats: cpb.GetRepeats(),
}
for i, val := range values {
c.Values[i], err = tablecodec.Unflatten(val, &cInfo.FieldType)
if err != nil {
return nil, errors.Trace(err)
}
}
t.Columns[i] = c
}
return t, nil
}
// DecodeValues decodes a byte slice into datums with column types.
func DecodeValues(data []byte, fts []*types.FieldType, inIndex bool) ([]types.Datum, error) {
if data == nil {
return nil, nil
}
values, err := codec.Decode(data)
if err != nil {
return nil, errors.Trace(err)
}
if len(values) > len(fts) {
return nil, errInvalidColumnCount.Gen("invalid column count %d is less than value count %d", len(fts), len(values))
}
if inIndex {
// We don't need to unflatten index columns for now.
return values, nil
}
for i := range values {
values[i], err = unflatten(values[i], fts[i])
if err != nil {
return nil, errors.Trace(err)
}
}
return values, nil
}
// DecodeIndexKey decodes datums from an index key.
func DecodeIndexKey(key kv.Key) ([]types.Datum, error) {
b := key[prefixLen+idLen:]
return codec.Decode(b, 1)
}
func (s *testXAPISuite) TestSelect(c *C) {
defer testleak.AfterTest(c)()
store := createMemStore(time.Now().Nanosecond())
count := int64(10)
err := prepareTableData(store, tbInfo, count, genValues)
c.Check(err, IsNil)
// Select Table request.
txn, err := store.Begin()
c.Check(err, IsNil)
client := txn.GetClient()
req, err := prepareSelectRequest(tbInfo, txn.StartTS())
c.Check(err, IsNil)
resp := client.Send(req)
subResp, err := resp.Next()
c.Check(err, IsNil)
data, err := ioutil.ReadAll(subResp)
c.Check(err, IsNil)
selResp := new(tipb.SelectResponse)
proto.Unmarshal(data, selResp)
c.Check(selResp.Rows, HasLen, int(count))
for i, row := range selResp.Rows {
handle := int64(i + 1)
expectedDatums := []types.Datum{types.NewDatum(handle)}
expectedDatums = append(expectedDatums, genValues(handle, tbInfo)...)
var expectedEncoded []byte
expectedEncoded, err = codec.EncodeValue(nil, expectedDatums...)
c.Assert(err, IsNil)
c.Assert(row.Data, BytesEquals, expectedEncoded)
}
txn.Commit()
// Select Index request.
txn, err = store.Begin()
c.Check(err, IsNil)
client = txn.GetClient()
req, err = prepareIndexRequest(tbInfo, txn.StartTS())
c.Check(err, IsNil)
resp = client.Send(req)
subResp, err = resp.Next()
c.Check(err, IsNil)
data, err = ioutil.ReadAll(subResp)
c.Check(err, IsNil)
idxResp := new(tipb.SelectResponse)
proto.Unmarshal(data, idxResp)
c.Check(idxResp.Rows, HasLen, int(count))
handles := make([]int, 0, 10)
for _, row := range idxResp.Rows {
var err error
datums, err := codec.Decode(row.Handle)
c.Check(err, IsNil)
c.Check(datums, HasLen, 1)
handles = append(handles, int(datums[0].GetInt64()))
}
sort.Ints(handles)
for i, h := range handles {
c.Assert(h, Equals, i+1)
}
txn.Commit()
store.Close()
}