diff --git a/docs/2.0/example-mysql2kafka.toml b/docs/2.0/example-mysql2kafka.toml
index 4b0d9c66..37e5bdbc 100644
--- a/docs/2.0/example-mysql2kafka.toml
+++ b/docs/2.0/example-mysql2kafka.toml
@@ -54,7 +54,7 @@ id = "another_id"
 
 [output]
 type = "async-kafka"
-[output.config]
+[output.config.kafka-global-config]
 broker-addrs = ["1.2.3.4:9002"]
 mode = "async"
 
diff --git a/pkg/inputs/mysqlstream/binlog_tailer.go b/pkg/inputs/mysqlstream/binlog_tailer.go
index d3b1c50f..1e79c0fc 100644
--- a/pkg/inputs/mysqlstream/binlog_tailer.go
+++ b/pkg/inputs/mysqlstream/binlog_tailer.go
@@ -627,6 +627,12 @@ func (tailer *BinlogTailer) AppendMsgTxnBuffer(msg *core.Msg) {
 	if len(tailer.msgTxnBuffer) >= config.TxnBufferLimit {
 		tailer.FlushMsgTxnBuffer()
 		tailer.ClearMsgTxnBuffer()
+
+		// send heartbeat to prevent sliding window timeout
+		heartbeat := NewHeartbeatMsg(tailer.AfterMsgCommit)
+		if err := tailer.emitter.Emit(heartbeat); err != nil {
+			log.Fatalf("failed to emit heartbeat msg: %v", errors.ErrorStack(err))
+		}
 	}
 }
 
diff --git a/pkg/inputs/mysqlstream/msg.go b/pkg/inputs/mysqlstream/msg.go
index 741618ff..fa4a2a4e 100644
--- a/pkg/inputs/mysqlstream/msg.go
+++ b/pkg/inputs/mysqlstream/msg.go
@@ -30,6 +30,7 @@ const (
 	ddl              binlogOp = "ddl"
 	xid              binlogOp = "xid"
 	barrier          binlogOp = "barrier"
+	heartbeat        binlogOp = "heartbeat"
 )
 
 type inputContext struct {
@@ -369,6 +370,20 @@ func NewBarrierMsg(callback core.MsgCallbackFunc) *core.Msg {
 	}
 }
 
+func NewHeartbeatMsg(callback core.MsgCallbackFunc) *core.Msg {
+	return &core.Msg{
+		Type:                core.MsgCtl,
+		Timestamp:           time.Now(),
+		Done:                make(chan struct{}),
+		InputContext:        inputContext{op: heartbeat},
+		InputStreamKey:      utils.NewStringPtr(inputStreamKey),
+		AfterCommitCallback: callback,
+		Phase: core.Phase{
+			Start: time.Now(),
+		},
+	}
+}
+
 func NewXIDMsg(ts int64, received time.Time, callback core.MsgCallbackFunc, position config.MySQLBinlogPosition) *core.Msg {
 	return &core.Msg{
 		Phase: core.Phase{
diff --git a/pkg/outputs/mysql/mysql_test.go b/pkg/outputs/mysql/mysql_test.go
index e2342a1b..c14d6ceb 100644
--- a/pkg/outputs/mysql/mysql_test.go
+++ b/pkg/outputs/mysql/mysql_test.go
@@ -2,6 +2,8 @@ package mysql
 
 import (
 	"bytes"
+	"fmt"
+	"strings"
 	"testing"
 
 	"github.com/pingcap/parser/ast"
@@ -124,3 +126,17 @@ func TestDDL(t *testing.T) {
 		require.Equal(t, expected[i], b.String())
 	}
 }
+
+func TestVarchar0(t *testing.T) {
+	s := "CREATE TABLE a (`scene` varchar(0) NOT NULL DEFAULT ' ' COMMENT '场景')"
+
+	p := parser.New()
+	stmt, err := p.ParseOneStmt(s, "", "")
+	require.NoError(t, err)
+
+	writer := &strings.Builder{}
+	ctx := format.NewRestoreCtx(format.RestoreStringSingleQuotes|format.RestoreKeyWordLowercase|format.RestoreNameBackQuotes, writer)
+	err = stmt.Restore(ctx)
+	require.NoError(t, err)
+	fmt.Println(writer.String())
+}