// 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 {
err = <-pr.done
pr.fetched = true
if err != nil {
return 0, nil, err
}
}
if len(pr.resp.Chunks) > 0 {
// For new resp rows structure.
chunk := pr.getChunk()
if chunk == nil {
return 0, nil, nil
}
rowMeta := chunk.RowsMeta[pr.cursor]
if !pr.ignoreData {
rowData := chunk.RowsData[pr.dataOffset : pr.dataOffset+rowMeta.Length]
data, err = tablecodec.DecodeValues(rowData, pr.fields, pr.index)
if err != nil {
return 0, nil, errors.Trace(err)
}
pr.dataOffset += rowMeta.Length
}
if data == nil {
data = dummyData
}
if !pr.aggregate {
handle = rowMeta.Handle
}
pr.cursor++
return
}
if pr.cursor >= len(pr.resp.Rows) {
return 0, nil, nil
}
row := pr.resp.Rows[pr.cursor]
if !pr.ignoreData {
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)
data = dummyData
}
if !pr.aggregate {
handleBytes := row.GetHandle()
_, datum, err := codec.DecodeOne(handleBytes)
if err != nil {
return 0, nil, errors.Trace(err)
}
handle = datum.GetInt64()
}
pr.cursor++
return
}
// 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 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
}
