*: add a flag EncodeType for response to use Arrow/Default format to decode.

distsql/select_result.go

@@ -147,18 +147,14 @@ func (r *selectResult) NextRaw(ctx context.Context) (data []byte, err error) {
 func (r *selectResult) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	// Check the returned data is default/arrow format.
-	if r.selectResp == nil || (len(r.selectResp.RowBatchData) == 0 && r.respChkIdx == len(r.selectResp.Chunks)) {
+	if r.selectResp == nil || r.respChkIdx == len(r.selectResp.Chunks) {
 		err := r.getSelectResp()
 		if err != nil || r.selectResp == nil {
 			return err
 		}
-		// TODO(Shenghui Wu): add metrics
-		if len(r.selectResp.RowBatchData) == 0 {
-			r.encodeType = tipb.EncodeType_TypeDefault
-		}
 	}
-
-	switch r.encodeType {
+	// TODO(Shenghui Wu): add metrics
+	switch r.selectResp.EncodeType {
 	case tipb.EncodeType_TypeDefault:
 		return r.readFromDefault(ctx, chk)
 	case tipb.EncodeType_TypeArrow:
@@ -187,10 +183,10 @@ func (r *selectResult) readFromDefault(ctx context.Context, chk *chunk.Chunk) er
 }
 
 func (r *selectResult) readFromArrow(ctx context.Context, chk *chunk.Chunk) error {
-	rowBatchData := r.selectResp.RowBatchData
+	rowBatchData := r.selectResp.Chunks[r.respChkIdx].RowsData
 	codec := chunk.NewCodec(r.fieldTypes)
-	remained := codec.DecodeToChunk(rowBatchData, chk)
-	r.selectResp.RowBatchData = remained
+	_ = codec.DecodeToChunk(rowBatchData, chk)
+	r.respChkIdx++
 	return nil
 }
 
@@ -227,7 +223,7 @@ func (r *selectResult) getSelectResp() error {
 		r.feedback.Update(re.result.GetStartKey(), r.selectResp.OutputCounts)
 		r.partialCount++
 		sc.MergeExecDetails(re.result.GetExecDetails(), nil)
-		if len(r.selectResp.Chunks) == 0 && len(r.selectResp.RowBatchData) == 0 {
+		if len(r.selectResp.Chunks) == 0 {
 			continue
 		}
 		return nil

go.mod

@@ -43,7 +43,7 @@ require (
 	github.com/pingcap/parser v0.0.0-20190923031704-33636bc5e5d6
 	github.com/pingcap/pd v1.1.0-beta.0.20190923032047-5c648dc365e0
 	github.com/pingcap/tidb-tools v2.1.3-0.20190321065848-1e8b48f5c168+incompatible
-	github.com/pingcap/tipb v0.0.0-20190806070524-16909e03435e
+	github.com/pingcap/tipb v0.0.0-20191008064422-018b2fadf414
 	github.com/prometheus/client_golang v0.9.0
 	github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910
 	github.com/prometheus/common v0.0.0-20181020173914-7e9e6cabbd39 // indirect

go.sum

@@ -170,8 +170,8 @@ github.com/pingcap/pd v1.1.0-beta.0.20190923032047-5c648dc365e0 h1:GIEq+wZfrl2bc
 github.com/pingcap/pd v1.1.0-beta.0.20190923032047-5c648dc365e0/go.mod h1:G/6rJpnYwM0LKMec2rI82/5Kg6GaZMvlfB+e6/tvYmI=
 github.com/pingcap/tidb-tools v2.1.3-0.20190321065848-1e8b48f5c168+incompatible h1:MkWCxgZpJBgY2f4HtwWMMFzSBb3+JPzeJgF3VrXE/bU=
 github.com/pingcap/tidb-tools v2.1.3-0.20190321065848-1e8b48f5c168+incompatible/go.mod h1:XGdcy9+yqlDSEMTpOXnwf3hiTeqrV6MN/u1se9N8yIM=
-github.com/pingcap/tipb v0.0.0-20190806070524-16909e03435e h1:H7meq8QPmWGImOkHTQYAWw82zwIqndJaCDPVUknOHbM=
-github.com/pingcap/tipb v0.0.0-20190806070524-16909e03435e/go.mod h1:RtkHW8WbcNxj8lsbzjaILci01CtYnYbIkQhjyZWrWVI=
+github.com/pingcap/tipb v0.0.0-20191008064422-018b2fadf414 h1:1HaTk+HEzn0rVcsAbVz9GLB9Ft3/KeSl2Sy452tDkHk=
+github.com/pingcap/tipb v0.0.0-20191008064422-018b2fadf414/go.mod h1:RtkHW8WbcNxj8lsbzjaILci01CtYnYbIkQhjyZWrWVI=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=

store/mockstore/mocktikv/cop_handler_dag.go

@@ -609,10 +609,11 @@ func (h *rpcHandler) encodeDefault(selResp *tipb.SelectResponse, rows [][][]byte
 		chunks = appendRow(chunks, requestedRow, i)
 	}
 	selResp.Chunks = chunks
+	selResp.EncodeType = tipb.EncodeType_TypeDefault
 }
 
 func (h *rpcHandler) encodeArrow(selResp *tipb.SelectResponse, rows [][][]byte, colTypes []*types.FieldType, colOrdinal []uint32, loc *time.Location) error {
-	rowBatchData := make([]byte, 0, 1024)
+	var chunks []tipb.Chunk
 	respColTypes := make([]*types.FieldType, 0, len(colOrdinal))
 	for _, ordinal := range colOrdinal {
 		respColTypes = append(respColTypes, colTypes[ordinal])
@@ -628,15 +629,20 @@ func (h *rpcHandler) encodeArrow(selResp *tipb.SelectResponse, rows [][][]byte,
 			}
 		}
 		if i%rowsPerChunk == rowsPerChunk-1 {
-			rowBatchData = append(rowBatchData, encoder.Encode(chk)...)
+			chunks = append(chunks, tipb.Chunk{})
+			cur := &chunks[len(chunks)-1]
+			cur.RowsData = append(cur.RowsData, encoder.Encode(chk)...)
 			chk.Reset()
 		}
 	}
 	if chk.NumRows() > 0 {
-		rowBatchData = append(rowBatchData, encoder.Encode(chk)...)
+		chunks = append(chunks, tipb.Chunk{})
+		cur := &chunks[len(chunks)-1]
+		cur.RowsData = append(cur.RowsData, encoder.Encode(chk)...)
 		chk.Reset()
 	}
-	selResp.RowBatchData = rowBatchData
+	selResp.Chunks = chunks
+	selResp.EncodeType = tipb.EncodeType_TypeArrow
 	return nil
 }