diff --git a/pkg/container/vector/vector.go b/pkg/container/vector/vector.go
index e07bf281fa6b1..527fb2c167c7e 100644
--- a/pkg/container/vector/vector.go
+++ b/pkg/container/vector/vector.go
@@ -395,17 +395,23 @@ func (v *Vector) Dup(proc *process.Process) (*Vector, error) {
 			Ref:  v.Ref,
 		}, nil
 	case types.T_char, types.T_varchar, types.T_json:
+		var err error
+		var data []byte
+
 		vs := v.Col.(*types.Bytes)
-		data, err := proc.Alloc(int64(len(vs.Data)))
-		if err != nil {
-			return nil, err
-		}
 		ws := &types.Bytes{
-			Data:    data,
 			Offsets: make([]uint32, len(vs.Offsets)),
 			Lengths: make([]uint32, len(vs.Lengths)),
 		}
-		copy(ws.Data, vs.Data)
+		if len(vs.Data) > 0 {
+			if data, err = proc.Alloc(int64(len(vs.Data))); err != nil {
+				return nil, err
+			}
+			ws.Data = data
+			copy(ws.Data, vs.Data)
+		} else {
+			ws.Data = make([]byte, 0)
+		}
 		copy(ws.Offsets, vs.Offsets)
 		copy(ws.Lengths, vs.Lengths)
 		return &Vector{
diff --git a/pkg/sql/colexec/merge/merge.go b/pkg/sql/colexec/merge/merge.go
index 6b4ac2c1c9e7a..5019d0b9814c2 100644
--- a/pkg/sql/colexec/merge/merge.go
+++ b/pkg/sql/colexec/merge/merge.go
@@ -34,6 +34,9 @@ func Call(proc *process.Process, _ interface{}) (bool, error) {
 	}
 	for i := 0; i < len(proc.Reg.MergeReceivers); i++ {
 		reg := proc.Reg.MergeReceivers[i]
+		if reg.Ch == nil {
+			continue
+		}
 		v := <-reg.Ch
 		if v == nil {
 			reg.Ch = nil
diff --git a/pkg/sql/colexec/transfer/transfer.go b/pkg/sql/colexec/transfer/transfer.go
index 3a7ebe0765ee2..bc3cf7d6f1483 100644
--- a/pkg/sql/colexec/transfer/transfer.go
+++ b/pkg/sql/colexec/transfer/transfer.go
@@ -69,7 +69,7 @@ func Call(proc *process.Process, arg interface{}) (bool, error) {
 	vecs := n.vecs[:0]
 	for i := range bat.Vecs {
 		if bat.Vecs[i].Or {
-			vec, err := bat.Vecs[i].Dup(n.Proc)
+			vec, err := bat.Vecs[i].Dup(proc)
 			if err != nil {
 				clean(vecs, n.Proc)
 				return false, err
diff --git a/pkg/sql/compile/compile.go b/pkg/sql/compile/compile.go
index c957510dc707d..a78000cef6d22 100644
--- a/pkg/sql/compile/compile.go
+++ b/pkg/sql/compile/compile.go
@@ -71,8 +71,9 @@ func (c *compile) Build() ([]*Exec, error) {
 	es := make([]*Exec, len(stmts))
 	for i, stmt := range stmts {
 		es[i] = &Exec{
-			c:    c,
-			stmt: stmt,
+			c:          c,
+			stmt:       stmt,
+			affectRows: 0,
 		}
 	}
 	return es, nil
@@ -147,6 +148,18 @@ func (e *Exec) Columns() []*Col {
 	return e.resultCols
 }
 
+func (e *Exec) IncreaseAffectedRows(n uint64) {
+	e.affectRows += n
+}
+
+func (e *Exec) SetAffectedRows(n uint64) {
+	e.affectRows = n
+}
+
+func (e *Exec) GetAffectedRows() uint64 {
+	return e.affectRows
+}
+
 // Run applies the scopes to the specified data object
 // and run through the instruction in each of the scope.
 func (e *Exec) Run(ts uint64) error {
@@ -179,8 +192,10 @@ func (e *Exec) Run(ts uint64) error {
 		case Insert:
 			wg.Add(1)
 			go func(s *Scope) {
-				if err := s.Insert(ts); err != nil {
+				if rows, err := s.Insert(ts); err != nil {
 					e.err = err
+				} else {
+					e.SetAffectedRows(rows)
 				}
 				wg.Done()
 			}(e.scopes[i])
@@ -242,7 +257,6 @@ func (e *Exec) Run(ts uint64) error {
 			}(e.scopes[i])
 		}
 	}
-
 	wg.Wait()
 	return e.err
 }
diff --git a/pkg/sql/compile/scope.go b/pkg/sql/compile/scope.go
index 7489eb8085fc2..40c48214ee397 100644
--- a/pkg/sql/compile/scope.go
+++ b/pkg/sql/compile/scope.go
@@ -128,9 +128,11 @@ func (s *Scope) RemoteRun(e engine.Engine) error {
 
 	arg := s.Instructions[len(s.Instructions)-1].Arg.(*transfer.Argument)
 	defer func() {
-		arg.Reg.Wg.Add(1)
-		arg.Reg.Ch <- nil
-		arg.Reg.Wg.Wait()
+		if arg.Reg.Ch != nil {
+			arg.Reg.Wg.Add(1)
+			arg.Reg.Ch <- nil
+			arg.Reg.Wg.Wait()
+		}
 	}()
 	encoder, decoder := rpcserver.NewCodec(1 << 30)
 	conn := goetty.NewIOSession(goetty.WithCodec(encoder, decoder))
@@ -161,6 +163,12 @@ func (s *Scope) RemoteRun(e engine.Engine) error {
 		if err != nil {
 			return err
 		}
+		if arg.Reg.Ch == nil {
+			if bat != nil {
+				bat.Clean(s.Proc)
+			}
+			continue
+		}
 		arg.Reg.Wg.Add(1)
 		arg.Reg.Ch <- bat
 		arg.Reg.Wg.Wait()
@@ -168,10 +176,10 @@ func (s *Scope) RemoteRun(e engine.Engine) error {
 	return nil
 }
 
-func (s *Scope) Insert(ts uint64) error {
+func (s *Scope) Insert(ts uint64) (uint64, error) {
 	o, _ := s.Operator.(*insert.Insert)
 	defer o.R.Close()
-	return o.R.Write(ts, o.Bat)
+	return uint64(o.Bat.Vecs[0].Length()), o.R.Write(ts, o.Bat)
 }
 
 func (s *Scope) Explain(u interface{}, fill func(interface{}, *batch.Batch) error) error {
diff --git a/pkg/sql/compile/top.go b/pkg/sql/compile/top.go
index 16891cba8b4ed..b4b3ae90c6ac6 100644
--- a/pkg/sql/compile/top.go
+++ b/pkg/sql/compile/top.go
@@ -32,7 +32,7 @@ func (c *compile) compileTopOutput(o *top.Top, mp map[string]uint64) ([]*Scope,
 			mp[g.Name]++
 		}
 	}
-	ss, err := c.compile(o.Prev.(*projection.Projection), mp)
+	ss, err := c.compileOutput(o.Prev.(*projection.Projection), mp)
 	if err != nil {
 		return nil, err
 	}
diff --git a/pkg/sql/compile/types.go b/pkg/sql/compile/types.go
index 93cae2d5f5142..646dc711d3c00 100644
--- a/pkg/sql/compile/types.go
+++ b/pkg/sql/compile/types.go
@@ -85,6 +85,8 @@ type Exec struct {
 	resultCols []*Col
 	scopes     []*Scope
 	c          *compile
+	//affectRows stores the number of rows affected while insert / update / delete
+	affectRows uint64
 	//e a dbengine instance
 	e engine.Engine
 	//stmt ast of a single sql
diff --git a/pkg/sql/protocol/protocol.go b/pkg/sql/protocol/protocol.go
index bf3a777030f02..928d6b7b170d6 100644
--- a/pkg/sql/protocol/protocol.go
+++ b/pkg/sql/protocol/protocol.go
@@ -1126,8 +1126,10 @@ func EncodeVector(v *vector.Vector, buf *bytes.Buffer) error {
 				size += uint64(v)
 			}
 			buf.Write(encoding.EncodeUint64(size))
-			for i, j := int64(0), int64(cnt); i < j; i++ {
-				buf.Write(vs.Get(i))
+			if size > 0 {
+				for i, j := int64(0), int64(cnt); i < j; i++ {
+					buf.Write(vs.Get(i))
+				}
 			}
 		}
 	case types.T_tuple:
diff --git a/pkg/vm/pipeline/pipeline.go b/pkg/vm/pipeline/pipeline.go
index d51369b365ffa..a85a0ffd9b286 100644
--- a/pkg/vm/pipeline/pipeline.go
+++ b/pkg/vm/pipeline/pipeline.go
@@ -16,6 +16,8 @@ package pipeline
 
 import (
 	"bytes"
+	"fmt"
+	"matrixone/pkg/container/batch"
 	"matrixone/pkg/vm"
 	"matrixone/pkg/vm/engine"
 	"matrixone/pkg/vm/mempool"
@@ -86,6 +88,9 @@ func (p *Pipeline) Run(segs []engine.Segment, proc *process.Process) (bool, erro
 }
 
 func (p *Pipeline) RunMerge(proc *process.Process) (bool, error) {
+	var end bool
+	var err error
+
 	proc.Mp = mempool.New()
 	defer func() {
 		proc.Reg.InputBatch = nil
@@ -96,11 +101,13 @@ func (p *Pipeline) RunMerge(proc *process.Process) (bool, error) {
 		vm.Clean(p.instructions, proc)
 		return false, err
 	}
-	i := 0
 	for {
-		i++
 		proc.Reg.InputBatch = nil
-		if end, err := vm.Run(p.instructions, proc); err != nil || end {
+		if end, err = vm.Run(p.instructions, proc); err != nil || end {
+			{
+				fmt.Printf("+++%p begin clean\n", p)
+			}
+			p.clean(proc)
 			return end, err
 		}
 	}
@@ -121,6 +128,30 @@ func (p *Pipeline) prefetch(segs []engine.Segment, proc *process.Process) *queue
 	return q
 }
 
+func (p *Pipeline) clean(proc *process.Process) {
+	for _, reg := range proc.Reg.MergeReceivers {
+		if reg.Ch != nil {
+			v := <-reg.Ch
+			switch {
+			case v == nil:
+				reg.Ch = nil
+				reg.Wg.Done()
+			default:
+				bat := v.(*batch.Batch)
+				if bat == nil || bat.Attrs == nil {
+					reg.Ch = nil
+					reg.Wg.Done()
+				} else {
+					bat.Clean(proc)
+					reg.Ch = nil
+					reg.Wg.Done()
+				}
+			}
+		}
+	}
+
+}
+
 // prefetch
 func (q *queue) prefetch(attrs []string) error {
 	if q.prefetchIndex == len(q.blocks) {