From ccf6da1a464368a7d7547f7166338fca2ce98a92 Mon Sep 17 00:00:00 2001
From: HuaiyuXu <391585975@qq.com>
Date: Tue, 3 Apr 2018 20:00:30 +0800
Subject: [PATCH] *: rename NextChunk to Next (#6214)

---
 ast/ast.go                          |  4 +-
 cmd/benchdb/main.go                 |  2 +-
 ddl/util/util.go                    |  2 +-
 distsql/distsql.go                  | 27 ++------
 distsql/distsql_test.go             | 12 ++--
 distsql/stream.go                   | 12 +---
 executor/adapter.go                 |  8 +--
 executor/admin.go                   | 18 +++---
 executor/aggregate.go               | 14 ++---
 executor/analyze.go                 |  4 +-
 executor/checksum.go                |  4 +-
 executor/ddl.go                     |  4 +-
 executor/ddl_test.go                |  6 +-
 executor/distsql.go                 | 24 ++++----
 executor/distsql_test.go            |  8 +--
 executor/executor.go                | 96 ++++++++++++++---------------
 executor/executor_pkg_test.go       |  4 +-
 executor/executor_test.go           | 18 +++---
 executor/explain.go                 |  4 +-
 executor/grant.go                   |  4 +-
 executor/index_lookup_join.go       |  8 +--
 executor/join.go                    | 16 ++---
 executor/join_test.go               |  2 +-
 executor/load_stats.go              |  4 +-
 executor/merge_join.go              |  8 +--
 executor/pkg_test.go                |  4 +-
 executor/prepared.go                | 12 ++--
 executor/prepared_test.go           |  4 +-
 executor/revoke.go                  |  4 +-
 executor/set.go                     |  4 +-
 executor/show.go                    |  4 +-
 executor/simple.go                  |  4 +-
 executor/sort.go                    | 14 ++---
 executor/union_scan.go              |  6 +-
 executor/write.go                   | 28 ++++-----
 privilege/privileges/cache.go       |  2 +-
 server/conn.go                      |  6 +-
 server/driver.go                    |  2 +-
 server/driver_tidb.go               |  4 +-
 server/tidb_test.go                 |  4 +-
 session/bench_test.go               |  2 +-
 session/bootstrap.go                |  6 +-
 session/bootstrap_test.go           | 18 +++---
 session/session.go                  |  4 +-
 session/session_test.go             | 18 +++---
 session/tidb.go                     |  2 +-
 statistics/boostrap.go              |  6 +-
 statistics/ddl.go                   |  2 +-
 statistics/sample.go                |  2 +-
 statistics/statistics_test.go       |  6 +-
 store/mockstore/mocktikv/analyze.go | 11 +---
 store/tikv/gcworker/gc_worker.go    |  2 +-
 store/tikv/sql_fail_test.go         |  4 +-
 table/tables/tables_test.go         |  6 +-
 54 files changed, 233 insertions(+), 271 deletions(-)

diff --git a/ast/ast.go b/ast/ast.go
index dab6c3ac5d4fc..f61e9519b473c 100644
--- a/ast/ast.go
+++ b/ast/ast.go
@@ -137,8 +137,8 @@ type RecordSet interface {
 	// Fields gets result fields.
 	Fields() []*ResultField
 
-	// NextChunk reads records into chunk.
-	NextChunk(ctx context.Context, chk *chunk.Chunk) error
+	// Next reads records into chunk.
+	Next(ctx context.Context, chk *chunk.Chunk) error
 
 	// NewChunk creates a new chunk with initial capacity.
 	NewChunk() *chunk.Chunk
diff --git a/cmd/benchdb/main.go b/cmd/benchdb/main.go
index 67305fdeccb51..e6a91936b9869 100644
--- a/cmd/benchdb/main.go
+++ b/cmd/benchdb/main.go
@@ -119,7 +119,7 @@ func (ut *benchDB) mustExec(sql string) {
 		rs := rss[0]
 		chk := rs.NewChunk()
 		for {
-			err := rs.NextChunk(ctx, chk)
+			err := rs.Next(ctx, chk)
 			if err != nil {
 				log.Fatal(err)
 			}
diff --git a/ddl/util/util.go b/ddl/util/util.go
index eff6b8769431e..3761356bceb95 100644
--- a/ddl/util/util.go
+++ b/ddl/util/util.go
@@ -58,7 +58,7 @@ func LoadDeleteRanges(ctx sessionctx.Context, safePoint uint64) (ranges []DelRan
 	chk := rs.NewChunk()
 	it := chunk.NewIterator4Chunk(chk)
 	for {
-		err = rs.NextChunk(context.TODO(), chk)
+		err = rs.Next(context.TODO(), chk)
 		if err != nil {
 			return nil, errors.Trace(err)
 		}
diff --git a/distsql/distsql.go b/distsql/distsql.go
index 4fca9ba2bd854..a33b76532cb47 100644
--- a/distsql/distsql.go
+++ b/distsql/distsql.go
@@ -42,12 +42,10 @@ var (
 
 // SelectResult is an iterator of coprocessor partial results.
 type SelectResult interface {
-	// Next gets the next partial result.
-	Next(context.Context) (PartialResult, error)
 	// NextRaw gets the next raw result.
 	NextRaw(context.Context) ([]byte, error)
-	// NextChunk reads the data into chunk.
-	NextChunk(context.Context, *chunk.Chunk) error
+	// Next reads the data into chunk.
+	Next(context.Context, *chunk.Chunk) error
 	// Close closes the iterator.
 	Close() error
 	// Fetch fetches partial results from client.
@@ -121,23 +119,6 @@ func (r *selectResult) fetch(ctx context.Context) {
 	}
 }
 
-// Next returns the next row.
-func (r *selectResult) Next(ctx context.Context) (PartialResult, error) {
-	re := <-r.results
-	if re.err != nil {
-		return nil, errors.Trace(re.err)
-	}
-	if re.result == nil {
-		return nil, nil
-	}
-	pr := &partialResult{}
-	pr.rowLen = r.rowLen
-	err := pr.unmarshal(re.result.GetData())
-	r.feedback.Update(re.result.GetStartKey(), pr.resp.OutputCounts)
-	r.partialCount++
-	return pr, errors.Trace(err)
-}
-
 // NextRaw returns the next raw partial result.
 func (r *selectResult) NextRaw(ctx context.Context) ([]byte, error) {
 	re := <-r.results
@@ -149,8 +130,8 @@ func (r *selectResult) NextRaw(ctx context.Context) ([]byte, error) {
 	return re.result.GetData(), nil
 }
 
-// NextChunk reads data to the chunk.
-func (r *selectResult) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next reads data to the chunk.
+func (r *selectResult) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	for chk.NumRows() < r.ctx.GetSessionVars().MaxChunkSize {
 		if r.selectResp == nil || r.respChkIdx == len(r.selectResp.Chunks) {
diff --git a/distsql/distsql_test.go b/distsql/distsql_test.go
index 3bdd8ed723d6a..27c1fbbb411ac 100644
--- a/distsql/distsql_test.go
+++ b/distsql/distsql_test.go
@@ -54,7 +54,7 @@ func (s *testSuite) TestSelectNormal(c *C) {
 	colTypes = append(colTypes, colTypes[0])
 	colTypes = append(colTypes, colTypes[0])
 
-	// Test NextChunk.
+	// Test Next.
 	response, err := Select(context.TODO(), s.sctx, request, colTypes, statistics.NewQueryFeedback(0, nil, 0, false))
 	c.Assert(err, IsNil)
 	result, ok := response.(*selectResult)
@@ -64,11 +64,11 @@ func (s *testSuite) TestSelectNormal(c *C) {
 
 	response.Fetch(context.TODO())
 
-	// Test NextChunk.
+	// Test Next.
 	chk := chunk.NewChunk(colTypes)
 	numAllRows := 0
 	for {
-		err = response.NextChunk(context.TODO(), chk)
+		err = response.Next(context.TODO(), chk)
 		c.Assert(err, IsNil)
 		numAllRows += chk.NumRows()
 		if chk.NumRows() == 0 {
@@ -108,7 +108,7 @@ func (s *testSuite) TestSelectStreaming(c *C) {
 
 	s.sctx.GetSessionVars().EnableStreaming = true
 
-	// Test NextChunk.
+	// Test Next.
 	response, err := Select(context.TODO(), s.sctx, request, colTypes, statistics.NewQueryFeedback(0, nil, 0, false))
 	c.Assert(err, IsNil)
 	result, ok := response.(*streamResult)
@@ -117,11 +117,11 @@ func (s *testSuite) TestSelectStreaming(c *C) {
 
 	response.Fetch(context.TODO())
 
-	// Test NextChunk.
+	// Test Next.
 	chk := chunk.NewChunk(colTypes)
 	numAllRows := 0
 	for {
-		err = response.NextChunk(context.TODO(), chk)
+		err = response.Next(context.TODO(), chk)
 		c.Assert(err, IsNil)
 		numAllRows += chk.NumRows()
 		if chk.NumRows() == 0 {
diff --git a/distsql/stream.go b/distsql/stream.go
index bdbf241efb130..e14edb4c4a29c 100644
--- a/distsql/stream.go
+++ b/distsql/stream.go
@@ -41,17 +41,7 @@ type streamResult struct {
 
 func (r *streamResult) Fetch(context.Context) {}
 
-func (r *streamResult) Next(ctx context.Context) (PartialResult, error) {
-	var ret streamPartialResult
-	ret.rowLen = r.rowLen
-	finished, err := r.readDataFromResponse(ctx, r.resp, &ret.Chunk)
-	if err != nil || finished {
-		return nil, errors.Trace(err)
-	}
-	return &ret, nil
-}
-
-func (r *streamResult) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+func (r *streamResult) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	maxChunkSize := r.ctx.GetSessionVars().MaxChunkSize
 	for chk.NumRows() < maxChunkSize {
diff --git a/executor/adapter.go b/executor/adapter.go
index 8186c4db59326..63388b0660c70 100644
--- a/executor/adapter.go
+++ b/executor/adapter.go
@@ -79,13 +79,13 @@ func schema2ResultFields(schema *expression.Schema, defaultDB string) (rfs []*as
 	return rfs
 }
 
-// NextChunk use uses recordSet's executor to get next available chunk for later usage.
+// Next use uses recordSet's executor to get next available chunk for later usage.
 // If chunk does not contain any rows, then we update last query found rows in session variable as current found rows.
 // The reason we need update is that chunk with 0 rows indicating we already finished current query, we need prepare for
 // next query.
 // If stmt is not nil and chunk with some rows inside, we simply update last query found rows by the number of row in chunk.
-func (a *recordSet) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
-	err := a.executor.NextChunk(ctx, chk)
+func (a *recordSet) Next(ctx context.Context, chk *chunk.Chunk) error {
+	err := a.executor.Next(ctx, chk)
 	if err != nil {
 		a.lastErr = err
 		return errors.Trace(err)
@@ -262,7 +262,7 @@ func (a *ExecStmt) handleNoDelayExecutor(ctx context.Context, sctx sessionctx.Co
 		a.logSlowQuery(txnTS, err == nil)
 	}()
 
-	err = e.NextChunk(ctx, e.newChunk())
+	err = e.Next(ctx, e.newChunk())
 	if err != nil {
 		return nil, errors.Trace(err)
 	}
diff --git a/executor/admin.go b/executor/admin.go
index 7d6e0953289b8..5e3243f7182ec 100644
--- a/executor/admin.go
+++ b/executor/admin.go
@@ -58,12 +58,12 @@ type CheckIndexRangeExec struct {
 	cols   []*model.ColumnInfo
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *CheckIndexRangeExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *CheckIndexRangeExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	handleIdx := e.schema.Len() - 1
 	for {
-		err := e.result.NextChunk(ctx, e.srcChunk)
+		err := e.result.Next(ctx, e.srcChunk)
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -318,7 +318,7 @@ func (e *RecoverIndexExec) fetchRecoverRows(ctx context.Context, srcResult dists
 	result.scanRowCount = 0
 
 	for {
-		err := srcResult.NextChunk(ctx, e.srcChunk)
+		err := srcResult.Next(ctx, e.srcChunk)
 		if err != nil {
 			return nil, errors.Trace(err)
 		}
@@ -428,8 +428,8 @@ func (e *RecoverIndexExec) backfillIndexInTxn(ctx context.Context, txn kv.Transa
 	return result, nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *RecoverIndexExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *RecoverIndexExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.done {
 		return nil
@@ -537,7 +537,7 @@ func (e *CleanupIndexExec) fetchIndex(ctx context.Context, txn kv.Transaction) e
 
 	sc := e.ctx.GetSessionVars().StmtCtx
 	for {
-		err := result.NextChunk(ctx, e.idxChunk)
+		err := result.Next(ctx, e.idxChunk)
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -563,8 +563,8 @@ func (e *CleanupIndexExec) fetchIndex(ctx context.Context, txn kv.Transaction) e
 	}
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *CleanupIndexExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *CleanupIndexExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.done {
 		return nil
diff --git a/executor/aggregate.go b/executor/aggregate.go
index 6cb7a10e7b086..ab94b2f138d98 100644
--- a/executor/aggregate.go
+++ b/executor/aggregate.go
@@ -74,8 +74,8 @@ func (e *HashAggExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *HashAggExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *HashAggExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	// In this stage we consider all data from src as a single group.
 	if !e.executed {
 		err := e.execute(ctx)
@@ -110,11 +110,11 @@ func (e *HashAggExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
 	}
 }
 
-// innerNextChunk fetches Chunks from src and update each aggregate function for each row in Chunk.
+// execute fetches Chunks from src and update each aggregate function for each row in Chunk.
 func (e *HashAggExec) execute(ctx context.Context) (err error) {
 	inputIter := chunk.NewIterator4Chunk(e.childrenResults[0])
 	for {
-		err := e.children[0].NextChunk(ctx, e.childrenResults[0])
+		err := e.children[0].Next(ctx, e.childrenResults[0])
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -217,8 +217,8 @@ func (e *StreamAggExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *StreamAggExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *StreamAggExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 
 	for !e.executed && chk.NumRows() < e.maxChunkSize {
@@ -264,7 +264,7 @@ func (e *StreamAggExec) fetchChildIfNecessary(ctx context.Context, chk *chunk.Ch
 		return nil
 	}
 
-	err := e.children[0].NextChunk(ctx, e.childrenResults[0])
+	err := e.children[0].Next(ctx, e.childrenResults[0])
 	if err != nil {
 		return errors.Trace(err)
 	}
diff --git a/executor/analyze.go b/executor/analyze.go
index acfaba16b5e0a..c7d50fa5b8f7d 100644
--- a/executor/analyze.go
+++ b/executor/analyze.go
@@ -52,8 +52,8 @@ const (
 	defaultCMSketchWidth = 2048
 )
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *AnalyzeExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *AnalyzeExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	concurrency, err := getBuildStatsConcurrency(e.ctx)
 	if err != nil {
 		return errors.Trace(err)
diff --git a/executor/checksum.go b/executor/checksum.go
index e3b21953c6c0b..0beeaa89ef7ad 100644
--- a/executor/checksum.go
+++ b/executor/checksum.go
@@ -82,8 +82,8 @@ func (e *ChecksumTableExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *ChecksumTableExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *ChecksumTableExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.done {
 		return nil
diff --git a/executor/ddl.go b/executor/ddl.go
index bcf2f77a30cb4..29830223316d6 100644
--- a/executor/ddl.go
+++ b/executor/ddl.go
@@ -38,8 +38,8 @@ type DDLExec struct {
 	done bool
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *DDLExec) NextChunk(ctx context.Context, chk *chunk.Chunk) (err error) {
+// Next implements the Executor Next interface.
+func (e *DDLExec) Next(ctx context.Context, chk *chunk.Chunk) (err error) {
 	if e.done {
 		return nil
 	}
diff --git a/executor/ddl_test.go b/executor/ddl_test.go
index 265034802b25e..11597c2a36c8c 100644
--- a/executor/ddl_test.go
+++ b/executor/ddl_test.go
@@ -68,7 +68,7 @@ func (s *testSuite) TestCreateTable(c *C) {
 	chk := rs.NewChunk()
 	it := chunk.NewIterator4Chunk(chk)
 	for {
-		err1 := rs.NextChunk(ctx, chk)
+		err1 := rs.Next(ctx, chk)
 		c.Assert(err1, IsNil)
 		if chk.NumRows() == 0 {
 			break
@@ -82,7 +82,7 @@ func (s *testSuite) TestCreateTable(c *C) {
 	chk = rs.NewChunk()
 	it = chunk.NewIterator4Chunk(chk)
 	for {
-		err1 := rs.NextChunk(ctx, chk)
+		err1 := rs.Next(ctx, chk)
 		c.Assert(err1, IsNil)
 		if chk.NumRows() == 0 {
 			break
@@ -156,7 +156,7 @@ func (s *testSuite) TestAlterTableAddColumn(c *C) {
 	r, err := tk.Exec("select c2 from alter_test")
 	c.Assert(err, IsNil)
 	chk := r.NewChunk()
-	err = r.NextChunk(context.Background(), chk)
+	err = r.Next(context.Background(), chk)
 	c.Assert(err, IsNil)
 	row := chk.GetRow(0)
 	c.Assert(row.Len(), Equals, 1)
diff --git a/executor/distsql.go b/executor/distsql.go
index 81e688295b04a..465e6746226a3 100644
--- a/executor/distsql.go
+++ b/executor/distsql.go
@@ -78,7 +78,7 @@ type lookupTableTask struct {
 	//   4. task.memTracker.Consume(-task.memUsage)
 	//
 	// Step 1~3 are completed in "tableWorker.executeTask".
-	// Step 4   is  completed in "IndexLookUpExecutor.NextChunk".
+	// Step 4   is  completed in "IndexLookUpExecutor.Next".
 	memUsage   int64
 	memTracker *memory.Tracker
 }
@@ -219,9 +219,9 @@ func (e *TableReaderExecutor) Close() error {
 	return errors.Trace(err)
 }
 
-// NextChunk fills data into the chunk passed by its caller.
+// Next fills data into the chunk passed by its caller.
 // The task was actually done by tableReaderHandler.
-func (e *TableReaderExecutor) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+func (e *TableReaderExecutor) Next(ctx context.Context, chk *chunk.Chunk) error {
 	err := e.resultHandler.nextChunk(ctx, chk)
 	if err != nil {
 		e.feedback.Invalidate()
@@ -357,9 +357,9 @@ func (e *IndexReaderExecutor) Close() error {
 	return errors.Trace(err)
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *IndexReaderExecutor) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
-	err := e.result.NextChunk(ctx, chk)
+// Next implements the Executor Next interface.
+func (e *IndexReaderExecutor) Next(ctx context.Context, chk *chunk.Chunk) error {
+	err := e.result.Next(ctx, chk)
 	if err != nil {
 		e.feedback.Invalidate()
 	}
@@ -588,8 +588,8 @@ func (e *IndexLookUpExecutor) Close() error {
 	return nil
 }
 
-// NextChunk implements Exec NextChunk interface.
-func (e *IndexLookUpExecutor) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements Exec Next interface.
+func (e *IndexLookUpExecutor) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	for {
 		resultTask, err := e.getResultTask()
@@ -691,7 +691,7 @@ func (w *indexWorker) fetchHandles(ctx context.Context, result distsql.SelectRes
 func (w *indexWorker) extractTaskHandles(ctx context.Context, chk *chunk.Chunk, idxResult distsql.SelectResult) (handles []int64, err error) {
 	handles = make([]int64, 0, w.batchSize)
 	for len(handles) < w.batchSize {
-		err = errors.Trace(idxResult.NextChunk(ctx, chk))
+		err = errors.Trace(idxResult.Next(ctx, chk))
 		if err != nil {
 			return handles, err
 		}
@@ -789,7 +789,7 @@ func (w *tableWorker) executeTask(ctx context.Context, task *lookupTableTask) er
 	task.rows = make([]chunk.Row, 0, handleCnt)
 	for {
 		chk := tableReader.newChunk()
-		err = tableReader.NextChunk(ctx, chk)
+		err = tableReader.Next(ctx, chk)
 		if err != nil {
 			log.Error(err)
 			return errors.Trace(err)
@@ -880,7 +880,7 @@ func (tr *tableResultHandler) open(optionalResult, result distsql.SelectResult)
 
 func (tr *tableResultHandler) nextChunk(ctx context.Context, chk *chunk.Chunk) error {
 	if !tr.optionalFinished {
-		err := tr.optionalResult.NextChunk(ctx, chk)
+		err := tr.optionalResult.Next(ctx, chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -889,7 +889,7 @@ func (tr *tableResultHandler) nextChunk(ctx context.Context, chk *chunk.Chunk) e
 		}
 		tr.optionalFinished = true
 	}
-	return tr.result.NextChunk(ctx, chk)
+	return tr.result.Next(ctx, chk)
 }
 
 func (tr *tableResultHandler) nextRaw(ctx context.Context) (data []byte, err error) {
diff --git a/executor/distsql_test.go b/executor/distsql_test.go
index e0dcd23d6ddc3..988c627741d75 100644
--- a/executor/distsql_test.go
+++ b/executor/distsql_test.go
@@ -55,7 +55,7 @@ func (s *testSuite) TestIndexDoubleReadClose(c *C) {
 	rs, err := tk.Exec("select * from dist where c_idx between 0 and 100")
 	c.Assert(err, IsNil)
 	chk := rs.NewChunk()
-	err = rs.NextChunk(context.Background(), chk)
+	err = rs.Next(context.Background(), chk)
 	c.Assert(err, IsNil)
 	c.Assert(err, IsNil)
 	keyword := "pickAndExecTask"
@@ -106,7 +106,7 @@ func (s *testSuite) TestCopClientSend(c *C) {
 	c.Assert(err, IsNil)
 	defer rs.Close()
 	chk := rs.NewChunk()
-	err = rs.NextChunk(ctx, chk)
+	err = rs.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.GetRow(0).GetMyDecimal(0).String(), Equals, "499500")
 
@@ -120,7 +120,7 @@ func (s *testSuite) TestCopClientSend(c *C) {
 	rs, err = tk.Exec("select sum(id) from copclient")
 	c.Assert(err, IsNil)
 	chk = rs.NewChunk()
-	err = rs.NextChunk(ctx, chk)
+	err = rs.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.GetRow(0).GetMyDecimal(0).String(), Equals, "499500")
 	rs.Close()
@@ -129,7 +129,7 @@ func (s *testSuite) TestCopClientSend(c *C) {
 	rs, err = tk.Exec("select * from copclient order by id")
 	c.Assert(err, IsNil)
 	chk = rs.NewChunk()
-	err = rs.NextChunk(ctx, chk)
+	err = rs.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	rs.Close()
 	keyword := "(*copIterator).work"
diff --git a/executor/executor.go b/executor/executor.go
index 65f7bc068b6bc..cbc56398b0fc2 100644
--- a/executor/executor.go
+++ b/executor/executor.go
@@ -157,8 +157,8 @@ func (e *baseExecutor) retTypes() []*types.FieldType {
 	return e.retFieldTypes
 }
 
-// NextChunk fills mutiple rows into a chunk.
-func (e *baseExecutor) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next fills mutiple rows into a chunk.
+func (e *baseExecutor) Next(ctx context.Context, chk *chunk.Chunk) error {
 	return nil
 }
 
@@ -187,9 +187,9 @@ type Executor interface {
 	Schema() *expression.Schema
 	retTypes() []*types.FieldType
 	newChunk() *chunk.Chunk
-	// NextChunk fills a chunk with multiple rows
+	// Next fills a chunk with multiple rows
 	// NOTE: chunk has to call Reset() method before any use.
-	NextChunk(ctx context.Context, chk *chunk.Chunk) error
+	Next(ctx context.Context, chk *chunk.Chunk) error
 }
 
 // CancelDDLJobsExec represents a cancel DDL jobs executor.
@@ -201,8 +201,8 @@ type CancelDDLJobsExec struct {
 	errs   []error
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *CancelDDLJobsExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *CancelDDLJobsExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.cursor >= len(e.jobIDs) {
 		return nil
@@ -230,8 +230,8 @@ type ShowDDLExec struct {
 	done       bool
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *ShowDDLExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *ShowDDLExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.done {
 		return nil
@@ -289,8 +289,8 @@ func (e *ShowDDLJobQueriesExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *ShowDDLJobQueriesExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *ShowDDLJobQueriesExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.cursor >= len(e.jobs) {
 		return nil
@@ -330,8 +330,8 @@ func (e *ShowDDLJobsExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *ShowDDLJobsExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *ShowDDLJobsExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.cursor >= len(e.jobs) {
 		return nil
@@ -365,8 +365,8 @@ func (e *CheckTableExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *CheckTableExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *CheckTableExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	if e.done {
 		return nil
 	}
@@ -419,8 +419,8 @@ func (e *CheckIndexExec) Close() error {
 	return errors.Trace(e.src.Close())
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *CheckIndexExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *CheckIndexExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	if e.done {
 		return nil
 	}
@@ -432,7 +432,7 @@ func (e *CheckIndexExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error
 	}
 	chk = e.src.newChunk()
 	for {
-		err := e.src.NextChunk(ctx, chk)
+		err := e.src.Next(ctx, chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -470,10 +470,10 @@ func (e *SelectLockExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *SelectLockExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *SelectLockExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
-	err := e.children[0].NextChunk(ctx, chk)
+	err := e.children[0].Next(ctx, chk)
 	if err != nil {
 		return errors.Trace(err)
 	}
@@ -512,14 +512,14 @@ type LimitExec struct {
 	meetFirstBatch bool
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *LimitExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *LimitExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.cursor >= e.end {
 		return nil
 	}
 	for !e.meetFirstBatch {
-		err := e.children[0].NextChunk(ctx, e.childrenResults[0])
+		err := e.children[0].Next(ctx, e.childrenResults[0])
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -540,7 +540,7 @@ func (e *LimitExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
 		}
 		e.cursor += batchSize
 	}
-	err := e.children[0].NextChunk(ctx, chk)
+	err := e.children[0].Next(ctx, chk)
 	if err != nil {
 		return errors.Trace(err)
 	}
@@ -589,7 +589,7 @@ func init() {
 		}
 		for {
 			chk := exec.newChunk()
-			err = exec.NextChunk(ctx, chk)
+			err = exec.Next(ctx, chk)
 			if err != nil {
 				return rows, errors.Trace(err)
 			}
@@ -628,10 +628,10 @@ func (e *ProjectionExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *ProjectionExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *ProjectionExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
-	if err := e.children[0].NextChunk(ctx, e.childrenResults[0]); err != nil {
+	if err := e.children[0].Next(ctx, e.childrenResults[0]); err != nil {
 		return errors.Trace(err)
 	}
 	return errors.Trace(e.evaluatorSuit.Run(e.ctx, e.childrenResults[0], chk))
@@ -652,8 +652,8 @@ func (e *TableDualExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *TableDualExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *TableDualExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.numReturned >= e.numDualRows {
 		return nil
@@ -703,12 +703,12 @@ func (e *SelectionExec) Close() error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *SelectionExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *SelectionExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 
 	if !e.batched {
-		return errors.Trace(e.unBatchedNextChunk(ctx, chk))
+		return errors.Trace(e.unBatchedNext(ctx, chk))
 	}
 
 	for {
@@ -721,7 +721,7 @@ func (e *SelectionExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
 			}
 			chk.AppendRow(e.inputRow)
 		}
-		err := e.children[0].NextChunk(ctx, e.childrenResults[0])
+		err := e.children[0].Next(ctx, e.childrenResults[0])
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -737,10 +737,10 @@ func (e *SelectionExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
 	}
 }
 
-// unBatchedNextChunk filters input rows one by one and returns once an input row is selected.
+// unBatchedNext filters input rows one by one and returns once an input row is selected.
 // For sql with "SETVAR" in filter and "GETVAR" in projection, for example: "SELECT @a FROM t WHERE (@a := 2) > 0",
 // we have to set batch size to 1 to do the evaluation of filter and projection.
-func (e *SelectionExec) unBatchedNextChunk(ctx context.Context, chk *chunk.Chunk) error {
+func (e *SelectionExec) unBatchedNext(ctx context.Context, chk *chunk.Chunk) error {
 	for {
 		for ; e.inputRow != e.inputIter.End(); e.inputRow = e.inputIter.Next() {
 			selected, err := expression.EvalBool(e.ctx, e.filters, e.inputRow)
@@ -753,7 +753,7 @@ func (e *SelectionExec) unBatchedNextChunk(ctx context.Context, chk *chunk.Chunk
 				return nil
 			}
 		}
-		err := e.children[0].NextChunk(ctx, e.childrenResults[0])
+		err := e.children[0].Next(ctx, e.childrenResults[0])
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -780,8 +780,8 @@ type TableScanExec struct {
 	virtualTableChunkIdx  int
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *TableScanExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *TableScanExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.isVirtualTable {
 		return errors.Trace(e.nextChunk4InfoSchema(ctx, chk))
@@ -921,12 +921,12 @@ func (e *ExistsExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *ExistsExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *ExistsExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if !e.evaluated {
 		e.evaluated = true
-		err := e.children[0].NextChunk(ctx, e.childrenResults[0])
+		err := e.children[0].Next(ctx, e.childrenResults[0])
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -956,14 +956,14 @@ func (e *MaxOneRowExec) Open(ctx context.Context) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *MaxOneRowExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *MaxOneRowExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.evaluated {
 		return nil
 	}
 	e.evaluated = true
-	err := e.children[0].NextChunk(ctx, chk)
+	err := e.children[0].Next(ctx, chk)
 	if err != nil {
 		return errors.Trace(err)
 	}
@@ -1075,7 +1075,7 @@ func (e *UnionExec) resultPuller(ctx context.Context, childID int) {
 			return
 		case result.chk = <-e.resourcePools[childID]:
 		}
-		result.err = errors.Trace(e.children[childID].NextChunk(ctx, result.chk))
+		result.err = errors.Trace(e.children[childID].Next(ctx, result.chk))
 		if result.err == nil && result.chk.NumRows() == 0 {
 			return
 		}
@@ -1087,8 +1087,8 @@ func (e *UnionExec) resultPuller(ctx context.Context, childID int) {
 	}
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *UnionExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *UnionExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if !e.initialized {
 		e.initialize(ctx)
diff --git a/executor/executor_pkg_test.go b/executor/executor_pkg_test.go
index b8fb231e45627..95f547ae68039 100644
--- a/executor/executor_pkg_test.go
+++ b/executor/executor_pkg_test.go
@@ -89,13 +89,13 @@ func (s *testExecSuite) TestShowProcessList(c *C) {
 	it := chunk.NewIterator4Chunk(chk)
 	// Run test and check results.
 	for _, p := range ps {
-		err = e.NextChunk(context.Background(), chk)
+		err = e.Next(context.Background(), chk)
 		c.Assert(err, IsNil)
 		for row := it.Begin(); row != it.End(); row = it.Next() {
 			c.Assert(row.GetUint64(0), Equals, p.ID)
 		}
 	}
-	err = e.NextChunk(context.Background(), chk)
+	err = e.Next(context.Background(), chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows(), Equals, 0)
 	err = e.Close()
diff --git a/executor/executor_test.go b/executor/executor_test.go
index b3af7cb54bba8..c801d2267e6d4 100644
--- a/executor/executor_test.go
+++ b/executor/executor_test.go
@@ -138,7 +138,7 @@ func (s *testSuite) TestAdmin(c *C) {
 	r, err := tk.Exec("admin cancel ddl jobs 1")
 	c.Assert(err, IsNil, Commentf("err %v", err))
 	chk := r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	row := chk.GetRow(0)
 	c.Assert(row.Len(), Equals, 2)
@@ -148,7 +148,7 @@ func (s *testSuite) TestAdmin(c *C) {
 	r, err = tk.Exec("admin show ddl")
 	c.Assert(err, IsNil)
 	chk = r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	row = chk.GetRow(0)
 	c.Assert(row.Len(), Equals, 4)
@@ -163,7 +163,7 @@ func (s *testSuite) TestAdmin(c *C) {
 	// c.Assert(rowOwnerInfos[0], Equals, ownerInfos[0])
 	c.Assert(row.GetString(2), Equals, "")
 	chk = r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsTrue)
 	err = txn.Rollback()
@@ -173,7 +173,7 @@ func (s *testSuite) TestAdmin(c *C) {
 	r, err = tk.Exec("admin show ddl jobs")
 	c.Assert(err, IsNil)
 	chk = r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	row = chk.GetRow(0)
 	c.Assert(row.Len(), Equals, 2)
@@ -756,7 +756,7 @@ func (s *testSuite) TestIssue2612(c *C) {
 	rs, err := tk.Exec(`select timediff(finish_at, create_at) from t;`)
 	c.Assert(err, IsNil)
 	chk := rs.NewChunk()
-	err = rs.NextChunk(context.Background(), chk)
+	err = rs.Next(context.Background(), chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.GetRow(0).GetDuration(0).String(), Equals, "-46:09:02")
 }
@@ -2310,7 +2310,7 @@ func (s *testSuite) TestBit(c *C) {
 	r, err := tk.Exec("select * from t where c1 = 2")
 	c.Assert(err, IsNil)
 	chk := r.NewChunk()
-	err = r.NextChunk(context.Background(), chk)
+	err = r.Next(context.Background(), chk)
 	c.Assert(err, IsNil)
 	c.Assert(types.BinaryLiteral(chk.GetRow(0).GetBytes(0)), DeepEquals, types.NewBinaryLiteralFromUint(2, -1))
 
@@ -2475,7 +2475,7 @@ func (s *testSuite) TestEarlyClose(c *C) {
 		c.Assert(err1, IsNil)
 		rs := rss[0]
 		chk := rs.NewChunk()
-		err = rs.NextChunk(ctx, chk)
+		err = rs.Next(ctx, chk)
 		c.Assert(err, IsNil)
 		rs.Close()
 	}
@@ -2487,7 +2487,7 @@ func (s *testSuite) TestEarlyClose(c *C) {
 	c.Assert(err, IsNil)
 	rs := rss[0]
 	chk := rs.NewChunk()
-	err = rs.NextChunk(ctx, chk)
+	err = rs.Next(ctx, chk)
 	c.Assert(err, NotNil)
 	rs.Close()
 }
@@ -2653,7 +2653,7 @@ func (s *testSuite) TestCoprocessorStreamingFlag(c *C) {
 		rs, err := tk.Se.Execute(ctx1, test.sql)
 		c.Assert(err, IsNil)
 		chk := rs[0].NewChunk()
-		err = rs[0].NextChunk(ctx, chk)
+		err = rs[0].Next(ctx, chk)
 		c.Assert(err, IsNil)
 		rs[0].Close()
 	}
diff --git a/executor/explain.go b/executor/explain.go
index f7af00687fe49..781f026c736af 100644
--- a/executor/explain.go
+++ b/executor/explain.go
@@ -33,8 +33,8 @@ func (e *ExplainExec) Close() error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *ExplainExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *ExplainExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.cursor >= len(e.rows) {
 		return nil
diff --git a/executor/grant.go b/executor/grant.go
index d9522f6566250..5d82141cc8cea 100644
--- a/executor/grant.go
+++ b/executor/grant.go
@@ -52,8 +52,8 @@ type GrantExec struct {
 	done bool
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *GrantExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *GrantExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	if e.done {
 		return nil
 	}
diff --git a/executor/index_lookup_join.go b/executor/index_lookup_join.go
index 7fc096e18f836..409ac572fd0cf 100644
--- a/executor/index_lookup_join.go
+++ b/executor/index_lookup_join.go
@@ -186,8 +186,8 @@ func (e *IndexLookUpJoin) newInnerWorker(taskCh chan *lookUpJoinTask) *innerWork
 	return iw
 }
 
-// NextChunk implements the Executor interface.
-func (e *IndexLookUpJoin) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor interface.
+func (e *IndexLookUpJoin) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	e.joinResult.Reset()
 	for {
@@ -328,7 +328,7 @@ func (ow *outerWorker) buildTask(ctx context.Context) (*lookUpJoinTask, error) {
 
 	task.memTracker.Consume(task.outerResult.MemoryUsage())
 	for task.outerResult.NumRows() < ow.batchSize {
-		err := ow.executor.NextChunk(ctx, ow.executorChk)
+		err := ow.executor.Next(ctx, ow.executorChk)
 		if err != nil {
 			return task, errors.Trace(err)
 		}
@@ -514,7 +514,7 @@ func (iw *innerWorker) fetchInnerResults(ctx context.Context, task *lookUpJoinTa
 	innerResult.GetMemTracker().SetLabel("inner result")
 	innerResult.GetMemTracker().AttachTo(task.memTracker)
 	for {
-		err := innerExec.NextChunk(ctx, iw.executorChk)
+		err := innerExec.Next(ctx, iw.executorChk)
 		if err != nil {
 			return errors.Trace(err)
 		}
diff --git a/executor/join.go b/executor/join.go
index 8d91194f7ec67..3f2979350221d 100644
--- a/executor/join.go
+++ b/executor/join.go
@@ -211,7 +211,7 @@ func (e *HashJoinExec) fetchOuterChunks(ctx context.Context) {
 			}
 		}
 		outerResult := outerResource.chk
-		err := e.outerExec.NextChunk(ctx, outerResult)
+		err := e.outerExec.Next(ctx, outerResult)
 		if err != nil {
 			e.joinResultCh <- &hashjoinWorkerResult{
 				err: errors.Trace(err),
@@ -233,7 +233,7 @@ func (e *HashJoinExec) fetchInnerRows(ctx context.Context) (err error) {
 	e.innerResult.GetMemTracker().SetLabel("innerResult")
 	for {
 		chk := e.children[e.innerIdx].newChunk()
-		err = e.innerExec.NextChunk(ctx, chk)
+		err = e.innerExec.Next(ctx, chk)
 		if err != nil || chk.NumRows() == 0 {
 			return errors.Trace(err)
 		}
@@ -441,11 +441,11 @@ func (e *HashJoinExec) join2Chunk(workerID uint, outerChk *chunk.Chunk, joinResu
 	return true, joinResult
 }
 
-// NextChunk implements the Executor NextChunk interface.
+// Next implements the Executor Next interface.
 // hash join constructs the result following these steps:
 // step 1. fetch data from inner child and build a hash table;
 // step 2. fetch data from outer child in a background goroutine and probe the hash table in multiple join workers.
-func (e *HashJoinExec) NextChunk(ctx context.Context, chk *chunk.Chunk) (err error) {
+func (e *HashJoinExec) Next(ctx context.Context, chk *chunk.Chunk) (err error) {
 	if !e.prepared {
 		if err = e.fetchInnerRows(ctx); err != nil {
 			return errors.Trace(err)
@@ -571,7 +571,7 @@ func (e *NestedLoopApplyExec) fetchSelectedOuterRow(ctx context.Context, chk *ch
 	outerIter := chunk.NewIterator4Chunk(e.outerChunk)
 	for {
 		if e.outerChunkCursor >= e.outerChunk.NumRows() {
-			err := e.outerExec.NextChunk(ctx, e.outerChunk)
+			err := e.outerExec.Next(ctx, e.outerChunk)
 			if err != nil {
 				return nil, errors.Trace(err)
 			}
@@ -608,7 +608,7 @@ func (e *NestedLoopApplyExec) fetchAllInners(ctx context.Context) error {
 	e.innerList.Reset()
 	innerIter := chunk.NewIterator4Chunk(e.innerChunk)
 	for {
-		err := e.innerExec.NextChunk(ctx, e.innerChunk)
+		err := e.innerExec.Next(ctx, e.innerChunk)
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -628,8 +628,8 @@ func (e *NestedLoopApplyExec) fetchAllInners(ctx context.Context) error {
 	}
 }
 
-// NextChunk implements the Executor interface.
-func (e *NestedLoopApplyExec) NextChunk(ctx context.Context, chk *chunk.Chunk) (err error) {
+// Next implements the Executor interface.
+func (e *NestedLoopApplyExec) Next(ctx context.Context, chk *chunk.Chunk) (err error) {
 	chk.Reset()
 	for {
 		if e.innerIter == nil || e.innerIter.Current() == e.innerIter.End() {
diff --git a/executor/join_test.go b/executor/join_test.go
index 4f98122176b2c..e036b81bbbd46 100644
--- a/executor/join_test.go
+++ b/executor/join_test.go
@@ -742,7 +742,7 @@ func (s *testSuite) TestJoinLeak(c *C) {
 	result, err := tk.Exec("select * from t t1 left join (select 1) t2 on 1")
 	c.Assert(err, IsNil)
 	chk := result.NewChunk()
-	err = result.NextChunk(context.Background(), chk)
+	err = result.Next(context.Background(), chk)
 	c.Assert(err, IsNil)
 	time.Sleep(100 * time.Millisecond)
 	result.Close()
diff --git a/executor/load_stats.go b/executor/load_stats.go
index 6f524081ddba8..2e20a074206ed 100644
--- a/executor/load_stats.go
+++ b/executor/load_stats.go
@@ -50,8 +50,8 @@ func (k loadStatsVarKeyType) String() string {
 // LoadStatsVarKey is a variable key for load statistic.
 const LoadStatsVarKey loadStatsVarKeyType = 0
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *LoadStatsExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *LoadStatsExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if len(e.info.Path) == 0 {
 		return errors.New("Load Stats: file path is empty")
diff --git a/executor/merge_join.go b/executor/merge_join.go
index c8b528f468a2a..b869ce2449b1f 100644
--- a/executor/merge_join.go
+++ b/executor/merge_join.go
@@ -132,7 +132,7 @@ func (t *mergeJoinInnerTable) nextRow() (chunk.Row, error) {
 	if t.curRow == t.curIter.End() {
 		t.reallocReaderResult()
 		oldMemUsage := t.curResult.MemoryUsage()
-		err := t.reader.NextChunk(t.ctx, t.curResult)
+		err := t.reader.Next(t.ctx, t.curResult)
 		// error happens or no more data.
 		if err != nil || t.curResult.NumRows() == 0 {
 			t.curRow = t.curIter.End()
@@ -234,8 +234,8 @@ func (e *MergeJoinExec) prepare(ctx context.Context, chk *chunk.Chunk) error {
 	return nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *MergeJoinExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *MergeJoinExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if !e.prepared {
 		if err := e.prepare(ctx, chk); err != nil {
@@ -319,7 +319,7 @@ func (e *MergeJoinExec) fetchNextInnerRows() (err error) {
 // may not all belong to the same join key, but are guaranteed to be sorted
 // according to the join key.
 func (e *MergeJoinExec) fetchNextOuterRows(ctx context.Context) (err error) {
-	err = e.outerTable.reader.NextChunk(ctx, e.outerTable.chk)
+	err = e.outerTable.reader.Next(ctx, e.outerTable.chk)
 	if err != nil {
 		return errors.Trace(err)
 	}
diff --git a/executor/pkg_test.go b/executor/pkg_test.go
index e718b081c7aa4..3a4f9a9b1c6cd 100644
--- a/executor/pkg_test.go
+++ b/executor/pkg_test.go
@@ -26,7 +26,7 @@ type MockExec struct {
 	curRowIdx int
 }
 
-func (m *MockExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+func (m *MockExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	colTypes := m.retTypes()
 	for ; m.curRowIdx < len(m.Rows) && chk.NumRows() < m.maxChunkSize; m.curRowIdx++ {
@@ -97,7 +97,7 @@ func (s *pkgTestSuite) TestNestedLoopApply(c *C) {
 	joinChk := join.newChunk()
 	it := chunk.NewIterator4Chunk(joinChk)
 	for rowIdx := 1; ; {
-		err := join.NextChunk(ctx, joinChk)
+		err := join.Next(ctx, joinChk)
 		c.Check(err, IsNil)
 		if joinChk.NumRows() == 0 {
 			break
diff --git a/executor/prepared.go b/executor/prepared.go
index aff2d676a22da..bd84bead3fa91 100644
--- a/executor/prepared.go
+++ b/executor/prepared.go
@@ -93,8 +93,8 @@ func NewPrepareExec(ctx sessionctx.Context, is infoschema.InfoSchema, sqlTxt str
 	}
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *PrepareExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *PrepareExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	vars := e.ctx.GetSessionVars()
 	if e.ID != 0 {
 		// Must be the case when we retry a prepare.
@@ -184,8 +184,8 @@ type ExecuteExec struct {
 	plan      plan.Plan
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *ExecuteExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *ExecuteExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	return nil
 }
 
@@ -220,8 +220,8 @@ type DeallocateExec struct {
 	Name string
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *DeallocateExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *DeallocateExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	vars := e.ctx.GetSessionVars()
 	id, ok := vars.PreparedStmtNameToID[e.Name]
 	if !ok {
diff --git a/executor/prepared_test.go b/executor/prepared_test.go
index ec35ff2e6be7d..3c9f51016cc93 100644
--- a/executor/prepared_test.go
+++ b/executor/prepared_test.go
@@ -105,7 +105,7 @@ func (s *testSuite) TestPrepared(c *C) {
 		rs, err = stmt.Exec(ctx)
 		c.Assert(err, IsNil)
 		chk := rs.NewChunk()
-		err = rs.NextChunk(ctx, chk)
+		err = rs.Next(ctx, chk)
 		c.Assert(err, IsNil)
 		c.Assert(rs.Close(), IsNil)
 
@@ -176,7 +176,7 @@ func (s *testSuite) TestPrepared(c *C) {
 
 		// Coverage.
 		exec := &executor.ExecuteExec{}
-		exec.NextChunk(ctx, nil)
+		exec.Next(ctx, nil)
 		exec.Close()
 	}
 	cfg.PreparedPlanCache.Enabled = orgEnable
diff --git a/executor/revoke.go b/executor/revoke.go
index 6e98bbcc50652..38abbf07a8f22 100644
--- a/executor/revoke.go
+++ b/executor/revoke.go
@@ -50,8 +50,8 @@ type RevokeExec struct {
 	done bool
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *RevokeExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *RevokeExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	if e.done {
 		return nil
 	}
diff --git a/executor/set.go b/executor/set.go
index ee4f9fcff943e..43cfa8c74df53 100644
--- a/executor/set.go
+++ b/executor/set.go
@@ -42,8 +42,8 @@ type SetExecutor struct {
 	done bool
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *SetExecutor) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *SetExecutor) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.done {
 		return nil
diff --git a/executor/show.go b/executor/show.go
index 8ca2463ac9eec..6797d18f2eacc 100644
--- a/executor/show.go
+++ b/executor/show.go
@@ -61,8 +61,8 @@ type ShowExec struct {
 	cursor int
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *ShowExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *ShowExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.result == nil {
 		e.result = e.newChunk()
diff --git a/executor/simple.go b/executor/simple.go
index 59883b4025e45..a4d4387bccd81 100644
--- a/executor/simple.go
+++ b/executor/simple.go
@@ -47,8 +47,8 @@ type SimpleExec struct {
 	is        infoschema.InfoSchema
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *SimpleExec) NextChunk(ctx context.Context, chk *chunk.Chunk) (err error) {
+// Next implements the Executor Next interface.
+func (e *SimpleExec) Next(ctx context.Context, chk *chunk.Chunk) (err error) {
 	if e.done {
 		return nil
 	}
diff --git a/executor/sort.go b/executor/sort.go
index d93f4b024db00..e77455dd87eed 100644
--- a/executor/sort.go
+++ b/executor/sort.go
@@ -71,8 +71,8 @@ func (e *SortExec) Open(ctx context.Context) error {
 	return errors.Trace(e.children[0].Open(ctx))
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *SortExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *SortExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if !e.fetched {
 		err := e.fetchRowChunks(ctx)
@@ -112,7 +112,7 @@ func (e *SortExec) fetchRowChunks(ctx context.Context) error {
 	e.rowChunks.GetMemTracker().SetLabel("rowChunks")
 	for {
 		chk := chunk.NewChunk(fields)
-		err := e.children[0].NextChunk(ctx, chk)
+		err := e.children[0].Next(ctx, chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -294,8 +294,8 @@ func (e *TopNExec) Open(ctx context.Context) error {
 	return errors.Trace(e.SortExec.Open(ctx))
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *TopNExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *TopNExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if !e.fetched {
 		e.totalLimit = int(e.limit.Offset + e.limit.Count)
@@ -328,7 +328,7 @@ func (e *TopNExec) loadChunksUntilTotalLimit(ctx context.Context) error {
 	e.rowChunks.GetMemTracker().SetLabel("rowChunks")
 	for e.rowChunks.Len() < e.totalLimit {
 		srcChk := e.children[0].newChunk()
-		err := e.children[0].NextChunk(ctx, srcChk)
+		err := e.children[0].Next(ctx, srcChk)
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -364,7 +364,7 @@ func (e *TopNExec) executeTopN(ctx context.Context) error {
 	}
 	childRowChk := e.children[0].newChunk()
 	for {
-		err := e.children[0].NextChunk(ctx, childRowChk)
+		err := e.children[0].Next(ctx, childRowChk)
 		if err != nil {
 			return errors.Trace(err)
 		}
diff --git a/executor/union_scan.go b/executor/union_scan.go
index fec8cc32da422..d85d5229ce43d 100644
--- a/executor/union_scan.go
+++ b/executor/union_scan.go
@@ -113,8 +113,8 @@ type UnionScanExec struct {
 	cursor4SnapshotRows int
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (us *UnionScanExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (us *UnionScanExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	mutableRow := chunk.MutRowFromTypes(us.retTypes())
 	for i, batchSize := 0, us.ctx.GetSessionVars().MaxChunkSize; i < batchSize; i++ {
@@ -183,7 +183,7 @@ func (us *UnionScanExec) getSnapshotRow(ctx context.Context) (Row, error) {
 	us.snapshotRows = us.snapshotRows[:0]
 	for len(us.snapshotRows) == 0 {
 		chk := chunk.NewChunkWithCapacity(us.retTypes(), us.maxChunkSize)
-		err = us.children[0].NextChunk(ctx, chk)
+		err = us.children[0].Next(ctx, chk)
 		if err != nil || chk.NumRows() == 0 {
 			return nil, errors.Trace(err)
 		}
diff --git a/executor/write.go b/executor/write.go
index 1143e931b9f65..1f8cb2f8da01f 100644
--- a/executor/write.go
+++ b/executor/write.go
@@ -182,8 +182,8 @@ type DeleteExec struct {
 	finished bool
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *DeleteExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *DeleteExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.finished {
 		return nil
@@ -259,7 +259,7 @@ func (e *DeleteExec) deleteSingleTableByChunk(ctx context.Context) error {
 		chk := e.children[0].newChunk()
 		iter := chunk.NewIterator4Chunk(chk)
 
-		err := e.children[0].NextChunk(ctx, chk)
+		err := e.children[0].Next(ctx, chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -339,7 +339,7 @@ func (e *DeleteExec) deleteMultiTablesByChunk(ctx context.Context) error {
 		chk := e.children[0].newChunk()
 		iter := chunk.NewIterator4Chunk(chk)
 
-		err := e.children[0].NextChunk(ctx, chk)
+		err := e.children[0].Next(ctx, chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -711,8 +711,8 @@ func (k loadDataVarKeyType) String() string {
 // LoadDataVarKey is a variable key for load data.
 const LoadDataVarKey loadDataVarKeyType = 0
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *LoadData) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *LoadData) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	// TODO: support load data without local field.
 	if !e.IsLocal {
@@ -995,8 +995,8 @@ func batchMarkDupRows(ctx sessionctx.Context, t table.Table, rows [][]types.Datu
 	return rows, nil
 }
 
-// NextChunk implements Exec NextChunk interface.
-func (e *InsertExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements Exec Next interface.
+func (e *InsertExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.finished {
 		return nil
@@ -1268,7 +1268,7 @@ func (e *InsertValues) getRowsSelectChunk(ctx context.Context, cols []*table.Col
 		chk := selectExec.newChunk()
 		iter := chunk.NewIterator4Chunk(chk)
 
-		err := selectExec.NextChunk(ctx, chk)
+		err := selectExec.Next(ctx, chk)
 		if err != nil {
 			return nil, errors.Trace(err)
 		}
@@ -1580,8 +1580,8 @@ func (e *ReplaceExec) exec(ctx context.Context, rows [][]types.Datum) (Row, erro
 	return nil, nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *ReplaceExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *ReplaceExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if e.finished {
 		return nil
@@ -1673,8 +1673,8 @@ func (e *UpdateExec) exec(ctx context.Context, schema *expression.Schema) (Row,
 	return Row{}, nil
 }
 
-// NextChunk implements the Executor NextChunk interface.
-func (e *UpdateExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+// Next implements the Executor Next interface.
+func (e *UpdateExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	if !e.fetched {
 		err := e.fetchChunkRows(ctx)
@@ -1714,7 +1714,7 @@ func (e *UpdateExec) fetchChunkRows(ctx context.Context) error {
 	globalRowIdx := 0
 	for {
 		chk := chunk.NewChunk(fields)
-		err := e.children[0].NextChunk(ctx, chk)
+		err := e.children[0].Next(ctx, chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
diff --git a/privilege/privileges/cache.go b/privilege/privileges/cache.go
index 4f7d067841b61..6a127362a634d 100644
--- a/privilege/privileges/cache.go
+++ b/privilege/privileges/cache.go
@@ -186,7 +186,7 @@ func (p *MySQLPrivilege) loadTable(sctx sessionctx.Context, sql string,
 	chk := rs.NewChunk()
 	it := chunk.NewIterator4Chunk(chk)
 	for {
-		err = rs.NextChunk(context.TODO(), chk)
+		err = rs.Next(context.TODO(), chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
diff --git a/server/conn.go b/server/conn.go
index 74db5aba8c5f6..df2cb26a7b25a 100644
--- a/server/conn.go
+++ b/server/conn.go
@@ -955,13 +955,13 @@ func (cc *clientConn) writeChunks(ctx context.Context, rs ResultSet, binary bool
 	chk := rs.NewChunk()
 	gotColumnInfo := false
 	for {
-		// Here server.tidbResultSet implements NextChunk method.
-		err := rs.NextChunk(ctx, chk)
+		// Here server.tidbResultSet implements Next method.
+		err := rs.Next(ctx, chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
 		if !gotColumnInfo {
-			// We need to call NextChunk before we get columns.
+			// We need to call Next before we get columns.
 			// Otherwise, we will get incorrect columns info.
 			columns := rs.Columns()
 			err = cc.writeColumnInfo(columns)
diff --git a/server/driver.go b/server/driver.go
index 42968c6c2fd23..9b2b1eaceb598 100644
--- a/server/driver.go
+++ b/server/driver.go
@@ -119,6 +119,6 @@ type PreparedStatement interface {
 type ResultSet interface {
 	Columns() []*ColumnInfo
 	NewChunk() *chunk.Chunk
-	NextChunk(context.Context, *chunk.Chunk) error
+	Next(context.Context, *chunk.Chunk) error
 	Close() error
 }
diff --git a/server/driver_tidb.go b/server/driver_tidb.go
index 85735baccddc1..016561b2b18cd 100644
--- a/server/driver_tidb.go
+++ b/server/driver_tidb.go
@@ -293,8 +293,8 @@ func (trs *tidbResultSet) NewChunk() *chunk.Chunk {
 	return trs.recordSet.NewChunk()
 }
 
-func (trs *tidbResultSet) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
-	return trs.recordSet.NextChunk(ctx, chk)
+func (trs *tidbResultSet) Next(ctx context.Context, chk *chunk.Chunk) error {
+	return trs.recordSet.Next(ctx, chk)
 }
 
 func (trs *tidbResultSet) Close() error {
diff --git a/server/tidb_test.go b/server/tidb_test.go
index 3d030a8107dd6..ffdb3fdad39d0 100644
--- a/server/tidb_test.go
+++ b/server/tidb_test.go
@@ -400,7 +400,7 @@ func (ts *TidbTestSuite) TestCreateTableFlen(c *C) {
 	c.Assert(err, IsNil)
 	rs, err := qctx.Execute(ctx, "show create table t1")
 	chk := rs[0].NewChunk()
-	err = rs[0].NextChunk(ctx, chk)
+	err = rs[0].Next(ctx, chk)
 	c.Assert(err, IsNil)
 	cols := rs[0].Columns()
 	c.Assert(err, IsNil)
@@ -429,7 +429,7 @@ func (ts *TidbTestSuite) TestShowTablesFlen(c *C) {
 	c.Assert(err, IsNil)
 	rs, err := qctx.Execute(ctx, "show tables")
 	chk := rs[0].NewChunk()
-	err = rs[0].NextChunk(ctx, chk)
+	err = rs[0].Next(ctx, chk)
 	c.Assert(err, IsNil)
 	cols := rs[0].Columns()
 	c.Assert(err, IsNil)
diff --git a/session/bench_test.go b/session/bench_test.go
index accdb4e117935..777876e570c02 100644
--- a/session/bench_test.go
+++ b/session/bench_test.go
@@ -84,7 +84,7 @@ func prepareJoinBenchData(se Session, colType string, valueFormat string, valueC
 func readResult(ctx context.Context, rs ast.RecordSet, count int) {
 	chk := rs.NewChunk()
 	for count > 0 {
-		err := rs.NextChunk(ctx, chk)
+		err := rs.Next(ctx, chk)
 		if err != nil {
 			log.Fatal(err)
 		}
diff --git a/session/bootstrap.go b/session/bootstrap.go
index a00c5159232bc..06b05084c5514 100644
--- a/session/bootstrap.go
+++ b/session/bootstrap.go
@@ -275,7 +275,7 @@ func getTiDBVar(s Session, name string) (sVal string, isNull bool, e error) {
 	r := rs[0]
 	defer terror.Call(r.Close)
 	chk := r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	if err != nil || chk.NumRows() == 0 {
 		return "", true, errors.Trace(err)
 	}
@@ -489,7 +489,7 @@ func upgradeToVer12(s Session) {
 	defer terror.Call(r.Close)
 	chk := r.NewChunk()
 	it := chunk.NewIterator4Chunk(chk)
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	for err == nil && chk.NumRows() != 0 {
 		for row := it.Begin(); row != it.End(); row = it.Next() {
 			user := row.GetString(0)
@@ -501,7 +501,7 @@ func upgradeToVer12(s Session) {
 			updateSQL := fmt.Sprintf(`UPDATE mysql.user set password = "%s" where user="%s" and host="%s"`, newPass, user, host)
 			sqls = append(sqls, updateSQL)
 		}
-		err = r.NextChunk(ctx, chk)
+		err = r.Next(ctx, chk)
 	}
 	terror.MustNil(err)
 
diff --git a/session/bootstrap_test.go b/session/bootstrap_test.go
index 66cb14bbad793..2d6a7cbcb7f42 100644
--- a/session/bootstrap_test.go
+++ b/session/bootstrap_test.go
@@ -51,7 +51,7 @@ func (s *testBootstrapSuite) TestBootstrap(c *C) {
 	c.Assert(r, NotNil)
 	ctx := context.Background()
 	chk := r.NewChunk()
-	err := r.NextChunk(ctx, chk)
+	err := r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsFalse)
 	datums := ast.RowToDatums(chk.GetRow(0), r.Fields())
@@ -67,7 +67,7 @@ func (s *testBootstrapSuite) TestBootstrap(c *C) {
 	r = mustExecSQL(c, se, "SELECT COUNT(*) from mysql.global_variables;")
 	c.Assert(r, NotNil)
 	chk = r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.GetRow(0).GetInt64(0), Equals, globalVarsCount())
 
@@ -88,7 +88,7 @@ func (s *testBootstrapSuite) TestBootstrap(c *C) {
 	c.Assert(r, NotNil)
 
 	chk = r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	datums = ast.RowToDatums(chk.GetRow(0), r.Fields())
 	match(c, datums, 3)
@@ -148,7 +148,7 @@ func (s *testBootstrapSuite) testBootstrapWithError(c *C) {
 	mustExecSQL(c, se, "USE mysql;")
 	r := mustExecSQL(c, se, `select * from user;`)
 	chk := r.NewChunk()
-	err := r.NextChunk(ctx, chk)
+	err := r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsFalse)
 	row := chk.GetRow(0)
@@ -162,14 +162,14 @@ func (s *testBootstrapSuite) testBootstrapWithError(c *C) {
 	// Check global variables.
 	r = mustExecSQL(c, se, "SELECT COUNT(*) from mysql.global_variables;")
 	chk = r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	v := chk.GetRow(0)
 	c.Assert(v.GetInt64(0), Equals, globalVarsCount())
 
 	r = mustExecSQL(c, se, `SELECT VARIABLE_VALUE from mysql.TiDB where VARIABLE_NAME="bootstrapped";`)
 	chk = r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsFalse)
 	row = chk.GetRow(0)
@@ -192,7 +192,7 @@ func (s *testBootstrapSuite) TestUpgrade(c *C) {
 	// bootstrap with currentBootstrapVersion
 	r := mustExecSQL(c, se, `SELECT VARIABLE_VALUE from mysql.TiDB where VARIABLE_NAME="tidb_server_version";`)
 	chk := r.NewChunk()
-	err := r.NextChunk(ctx, chk)
+	err := r.Next(ctx, chk)
 	row := chk.GetRow(0)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsFalse)
@@ -221,7 +221,7 @@ func (s *testBootstrapSuite) TestUpgrade(c *C) {
 	// Make sure the version is downgraded.
 	r = mustExecSQL(c, se1, `SELECT VARIABLE_VALUE from mysql.TiDB where VARIABLE_NAME="tidb_server_version";`)
 	chk = r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsTrue)
 
@@ -236,7 +236,7 @@ func (s *testBootstrapSuite) TestUpgrade(c *C) {
 	se2 := newSession(c, store, s.dbName)
 	r = mustExecSQL(c, se2, `SELECT VARIABLE_VALUE from mysql.TiDB where VARIABLE_NAME="tidb_server_version";`)
 	chk = r.NewChunk()
-	err = r.NextChunk(ctx, chk)
+	err = r.Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsFalse)
 	row = chk.GetRow(0)
diff --git a/session/session.go b/session/session.go
index 3609a9f605f4d..e209bae05baf1 100644
--- a/session/session.go
+++ b/session/session.go
@@ -610,7 +610,7 @@ func drainRecordSet(ctx context.Context, rs ast.RecordSet) ([]types.Row, error)
 	var rows []types.Row
 	for {
 		chk := rs.NewChunk()
-		err := rs.NextChunk(ctx, chk)
+		err := rs.Next(ctx, chk)
 		if err != nil || chk.NumRows() == 0 {
 			return rows, errors.Trace(err)
 		}
@@ -860,7 +860,7 @@ func (s *session) PrepareStmt(sql string) (stmtID uint32, paramCount int, fields
 	// So we have to call PrepareTxnCtx here.
 	s.PrepareTxnCtx(ctx)
 	prepareExec := executor.NewPrepareExec(s, executor.GetInfoSchema(s), sql)
-	err = prepareExec.NextChunk(ctx, nil)
+	err = prepareExec.Next(ctx, nil)
 	if err != nil {
 		err = errors.Trace(err)
 		return
diff --git a/session/session_test.go b/session/session_test.go
index 95b1da81a7148..8cbff9ce28aef 100644
--- a/session/session_test.go
+++ b/session/session_test.go
@@ -934,7 +934,7 @@ func (s *testSessionSuite) TestResultType(c *C) {
 	rs, err := tk.Exec(`select cast(null as char(30))`)
 	c.Assert(err, IsNil)
 	chk := rs.NewChunk()
-	err = rs.NextChunk(context.Background(), chk)
+	err = rs.Next(context.Background(), chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.GetRow(0).IsNull(0), IsTrue)
 	c.Assert(rs.Fields()[0].Column.FieldType.Tp, Equals, mysql.TypeVarString)
@@ -1655,7 +1655,7 @@ func (s *testSchemaSuite) TestTableReaderChunk(c *C) {
 	var count int
 	var numChunks int
 	for {
-		err = rs.NextChunk(context.TODO(), chk)
+		err = rs.Next(context.TODO(), chk)
 		c.Assert(err, IsNil)
 		numRows := chk.NumRows()
 		if numRows == 0 {
@@ -1688,7 +1688,7 @@ func (s *testSchemaSuite) TestInsertExecChunk(c *C) {
 	var idx int
 	for {
 		chk := rs.NewChunk()
-		err = rs.NextChunk(context.TODO(), chk)
+		err = rs.Next(context.TODO(), chk)
 		c.Assert(err, IsNil)
 		if chk.NumRows() == 0 {
 			break
@@ -1722,7 +1722,7 @@ func (s *testSchemaSuite) TestUpdateExecChunk(c *C) {
 	var idx int
 	for {
 		chk := rs.NewChunk()
-		err = rs.NextChunk(context.TODO(), chk)
+		err = rs.Next(context.TODO(), chk)
 		c.Assert(err, IsNil)
 		if chk.NumRows() == 0 {
 			break
@@ -1757,7 +1757,7 @@ func (s *testSchemaSuite) TestDeleteExecChunk(c *C) {
 	c.Assert(err, IsNil)
 
 	chk := rs.NewChunk()
-	err = rs.NextChunk(context.TODO(), chk)
+	err = rs.Next(context.TODO(), chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows(), Equals, 1)
 
@@ -1789,7 +1789,7 @@ func (s *testSchemaSuite) TestDeleteMultiTableExecChunk(c *C) {
 	var idx int
 	for {
 		chk := rs.NewChunk()
-		err = rs.NextChunk(context.TODO(), chk)
+		err = rs.Next(context.TODO(), chk)
 		c.Assert(err, IsNil)
 
 		if chk.NumRows() == 0 {
@@ -1809,7 +1809,7 @@ func (s *testSchemaSuite) TestDeleteMultiTableExecChunk(c *C) {
 	c.Assert(err, IsNil)
 
 	chk := rs.NewChunk()
-	err = rs.NextChunk(context.TODO(), chk)
+	err = rs.Next(context.TODO(), chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows(), Equals, 0)
 	rs.Close()
@@ -1834,7 +1834,7 @@ func (s *testSchemaSuite) TestIndexLookUpReaderChunk(c *C) {
 	chk := rs.NewChunk()
 	var count int
 	for {
-		err = rs.NextChunk(context.TODO(), chk)
+		err = rs.Next(context.TODO(), chk)
 		c.Assert(err, IsNil)
 		numRows := chk.NumRows()
 		if numRows == 0 {
@@ -1854,7 +1854,7 @@ func (s *testSchemaSuite) TestIndexLookUpReaderChunk(c *C) {
 	chk = rs.NewChunk()
 	count = 0
 	for {
-		err = rs.NextChunk(context.TODO(), chk)
+		err = rs.Next(context.TODO(), chk)
 		c.Assert(err, IsNil)
 		numRows := chk.NumRows()
 		if numRows == 0 {
diff --git a/session/tidb.go b/session/tidb.go
index 55eda92682c26..edfd96c2c4ec3 100644
--- a/session/tidb.go
+++ b/session/tidb.go
@@ -222,7 +222,7 @@ func GetRows4Test(ctx context.Context, sctx sessionctx.Context, rs ast.RecordSet
 		chk := rs.NewChunk()
 		iter := chunk.NewIterator4Chunk(chk)
 
-		err := rs.NextChunk(ctx, chk)
+		err := rs.Next(ctx, chk)
 		if err != nil {
 			return nil, errors.Trace(err)
 		}
diff --git a/statistics/boostrap.go b/statistics/boostrap.go
index 8df521565221e..7b5f3d5fe21f2 100644
--- a/statistics/boostrap.go
+++ b/statistics/boostrap.go
@@ -61,7 +61,7 @@ func (h *Handle) initStatsMeta(is infoschema.InfoSchema) (statsCache, error) {
 	chk := rc[0].NewChunk()
 	iter := chunk.NewIterator4Chunk(chk)
 	for {
-		err := rc[0].NextChunk(context.TODO(), chk)
+		err := rc[0].Next(context.TODO(), chk)
 		if err != nil {
 			return nil, errors.Trace(err)
 		}
@@ -128,7 +128,7 @@ func (h *Handle) initStatsHistograms(is infoschema.InfoSchema, tables statsCache
 	chk := rc[0].NewChunk()
 	iter := chunk.NewIterator4Chunk(chk)
 	for {
-		err := rc[0].NextChunk(context.TODO(), chk)
+		err := rc[0].Next(context.TODO(), chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
@@ -198,7 +198,7 @@ func (h *Handle) initStatsBuckets(tables statsCache) error {
 	chk := rc[0].NewChunk()
 	iter := chunk.NewIterator4Chunk(chk)
 	for {
-		err := rc[0].NextChunk(context.TODO(), chk)
+		err := rc[0].Next(context.TODO(), chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
diff --git a/statistics/ddl.go b/statistics/ddl.go
index 145cb0b282906..8f4905e7677c8 100644
--- a/statistics/ddl.go
+++ b/statistics/ddl.go
@@ -101,7 +101,7 @@ func (h *Handle) insertColStats2KV(tableID int64, colInfo *model.ColumnInfo) err
 			return errors.Trace(err)
 		}
 		chk := rs[0].NewChunk()
-		err = rs[0].NextChunk(ctx, chk)
+		err = rs[0].Next(ctx, chk)
 		if err != nil {
 			return errors.Trace(err)
 		}
diff --git a/statistics/sample.go b/statistics/sample.go
index 33065fa35f986..279fb883b14f7 100644
--- a/statistics/sample.go
+++ b/statistics/sample.go
@@ -158,7 +158,7 @@ func (s SampleBuilder) CollectColumnStats() ([]*SampleCollector, *SortedBuilder,
 	chk := s.RecordSet.NewChunk()
 	it := chunk.NewIterator4Chunk(chk)
 	for {
-		err := s.RecordSet.NextChunk(ctx, chk)
+		err := s.RecordSet.Next(ctx, chk)
 		if err != nil {
 			return nil, nil, errors.Trace(err)
 		}
diff --git a/statistics/statistics_test.go b/statistics/statistics_test.go
index 41429322e3969..98e709816a5d6 100644
--- a/statistics/statistics_test.go
+++ b/statistics/statistics_test.go
@@ -82,7 +82,7 @@ func (r *recordSet) getNext() []types.Datum {
 	return row
 }
 
-func (r *recordSet) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+func (r *recordSet) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	row := r.getNext()
 	if row != nil {
@@ -174,7 +174,7 @@ func buildPK(sctx sessionctx.Context, numBuckets, id int64, records ast.RecordSe
 	ctx := context.Background()
 	for {
 		chk := records.NewChunk()
-		err := records.NextChunk(ctx, chk)
+		err := records.Next(ctx, chk)
 		if err != nil {
 			return 0, nil, errors.Trace(err)
 		}
@@ -200,7 +200,7 @@ func buildIndex(sctx sessionctx.Context, numBuckets, id int64, records ast.Recor
 	chk := records.NewChunk()
 	it := chunk.NewIterator4Chunk(chk)
 	for {
-		err := records.NextChunk(ctx, chk)
+		err := records.Next(ctx, chk)
 		if err != nil {
 			return 0, nil, nil, errors.Trace(err)
 		}
diff --git a/store/mockstore/mocktikv/analyze.go b/store/mockstore/mocktikv/analyze.go
index 7f8e0737613e2..b04647b19e997 100644
--- a/store/mockstore/mocktikv/analyze.go
+++ b/store/mockstore/mocktikv/analyze.go
@@ -210,16 +210,7 @@ func (e *analyzeColumnsExec) getNext(ctx context.Context) ([]types.Datum, error)
 	return datumRow, nil
 }
 
-// Next implements the ast.RecordSet Next interface.
-func (e *analyzeColumnsExec) Next(ctx context.Context) (types.Row, error) {
-	row, err := e.getNext(ctx)
-	if row == nil || err != nil {
-		return nil, errors.Trace(err)
-	}
-	return types.DatumRow(row), nil
-}
-
-func (e *analyzeColumnsExec) NextChunk(ctx context.Context, chk *chunk.Chunk) error {
+func (e *analyzeColumnsExec) Next(ctx context.Context, chk *chunk.Chunk) error {
 	chk.Reset()
 	row, err := e.getNext(ctx)
 	if row == nil || err != nil {
diff --git a/store/tikv/gcworker/gc_worker.go b/store/tikv/gcworker/gc_worker.go
index 955225ab549b6..5aa1622c1d415 100644
--- a/store/tikv/gcworker/gc_worker.go
+++ b/store/tikv/gcworker/gc_worker.go
@@ -889,7 +889,7 @@ func (w *GCWorker) loadValueFromSysTable(key string, s session.Session) (string,
 		return "", errors.Trace(err)
 	}
 	chk := rs[0].NewChunk()
-	err = rs[0].NextChunk(ctx, chk)
+	err = rs[0].Next(ctx, chk)
 	if err != nil {
 		return "", errors.Trace(err)
 	}
diff --git a/store/tikv/sql_fail_test.go b/store/tikv/sql_fail_test.go
index 643194cf2b72a..eec2437652c7f 100644
--- a/store/tikv/sql_fail_test.go
+++ b/store/tikv/sql_fail_test.go
@@ -73,7 +73,7 @@ func (s *testSQLSuite) TestFailBusyServerCop(c *C) {
 		}
 		c.Assert(err, IsNil)
 		chk := rs[0].NewChunk()
-		err = rs[0].NextChunk(context.Background(), chk)
+		err = rs[0].Next(context.Background(), chk)
 		c.Assert(err, IsNil)
 		c.Assert(chk.NumRows() == 0, IsFalse)
 		c.Assert(chk.GetRow(0).GetString(0), Equals, "True")
@@ -109,7 +109,7 @@ func (s *testSQLSuite) TestCoprocessorStreamRecvTimeout(c *C) {
 
 	chk := res[0].NewChunk()
 	for {
-		err := res[0].NextChunk(ctx, chk)
+		err := res[0].Next(ctx, chk)
 		c.Assert(err, IsNil)
 		if chk.NumRows() == 0 {
 			break
diff --git a/table/tables/tables_test.go b/table/tables/tables_test.go
index 4602503c9a6db..a056d7eec50ed 100644
--- a/table/tables/tables_test.go
+++ b/table/tables/tables_test.go
@@ -159,7 +159,7 @@ func (ts *testSuite) TestTypes(c *C) {
 	rs, err := ts.se.Execute(ctx, "select * from test.t where c1 = 1")
 	c.Assert(err, IsNil)
 	chk := rs[0].NewChunk()
-	err = rs[0].NextChunk(ctx, chk)
+	err = rs[0].Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsFalse)
 	_, err = ts.se.Execute(ctx, "drop table test.t")
@@ -172,7 +172,7 @@ func (ts *testSuite) TestTypes(c *C) {
 	rs, err = ts.se.Execute(ctx, "select * from test.t where c1 = 1")
 	c.Assert(err, IsNil)
 	chk = rs[0].NewChunk()
-	err = rs[0].NextChunk(ctx, chk)
+	err = rs[0].Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsFalse)
 	row := chk.GetRow(0)
@@ -187,7 +187,7 @@ func (ts *testSuite) TestTypes(c *C) {
 	rs, err = ts.se.Execute(ctx, "select c1 + 1 from test.t where c1 = 1")
 	c.Assert(err, IsNil)
 	chk = rs[0].NewChunk()
-	err = rs[0].NextChunk(ctx, chk)
+	err = rs[0].Next(ctx, chk)
 	c.Assert(err, IsNil)
 	c.Assert(chk.NumRows() == 0, IsFalse)
 	c.Assert(chk.GetRow(0).GetFloat64(0), DeepEquals, float64(2))