diff --git a/dtmcli/tcc.go b/dtmcli/tcc.go
index 9df1bd4..73d1172 100644
--- a/dtmcli/tcc.go
+++ b/dtmcli/tcc.go
@@ -24,7 +24,7 @@ type TccGlobalFunc func(tcc *Tcc) (*resty.Response, error)
 
 // TccGlobalTransaction begin a tcc global transaction
 // dtm dtm server address
-// gid 全局事务id
+// gid global transaction ID
 // tccFunc tcc事务函数，里面会定义全局事务的分支
 func TccGlobalTransaction(dtm string, gid string, tccFunc TccGlobalFunc) (rerr error) {
 	tcc := &Tcc{TransBase: *dtmimp.NewTransBase(gid, "tcc", dtm, "")}
diff --git a/dtmsvr/storage/boltdb/boltdb.go b/dtmsvr/storage/boltdb/boltdb.go
index d0cd912..eb3454d 100644
--- a/dtmsvr/storage/boltdb/boltdb.go
+++ b/dtmsvr/storage/boltdb/boltdb.go
@@ -13,7 +13,6 @@ import (
 	"time"
 
 	bolt "go.etcd.io/bbolt"
-	"gorm.io/gorm"
 
 	"github.com/dtm-labs/dtm/dtmcli/dtmimp"
 	"github.com/dtm-labs/dtm/dtmcli/logger"
@@ -298,8 +297,8 @@ func (s *BoltdbStore) FindBranches(gid string) []storage.TransBranchStore {
 	return branches
 }
 
-func (s *BoltdbStore) UpdateBranchesSql(branches []storage.TransBranchStore, updates []string) *gorm.DB {
-	return nil // not implemented
+func (s *BoltdbStore) UpdateBranches(branches []storage.TransBranchStore, updates []string) (int, error) {
+	return 0, nil // not implemented
 }
 
 func (s *BoltdbStore) LockGlobalSaveBranches(gid string, status string, branches []storage.TransBranchStore, branchStart int) {
diff --git a/dtmsvr/storage/redis/redis.go b/dtmsvr/storage/redis/redis.go
index f8cef4b..12ff277 100644
--- a/dtmsvr/storage/redis/redis.go
+++ b/dtmsvr/storage/redis/redis.go
@@ -7,7 +7,6 @@ import (
 	"time"
 
 	"github.com/go-redis/redis/v8"
-	"gorm.io/gorm"
 
 	"github.com/dtm-labs/dtm/dtmcli/dtmimp"
 	"github.com/dtm-labs/dtm/dtmcli/logger"
@@ -88,8 +87,8 @@ func (s *RedisStore) FindBranches(gid string) []storage.TransBranchStore {
 	return branches
 }
 
-func (s *RedisStore) UpdateBranchesSql(branches []storage.TransBranchStore, updates []string) *gorm.DB {
-	return nil // not implemented
+func (s *RedisStore) UpdateBranches(branches []storage.TransBranchStore, updates []string) (int, error) {
+	return 0, nil // not implemented
 }
 
 type argList struct {
diff --git a/dtmsvr/storage/sql/sql.go b/dtmsvr/storage/sql/sql.go
index 7e4e74d..02f85c0 100644
--- a/dtmsvr/storage/sql/sql.go
+++ b/dtmsvr/storage/sql/sql.go
@@ -63,11 +63,12 @@ func (s *SqlStore) FindBranches(gid string) []storage.TransBranchStore {
 	return branches
 }
 
-func (s *SqlStore) UpdateBranchesSql(branches []storage.TransBranchStore, updates []string) *gorm.DB {
-	return dbGet().Clauses(clause.OnConflict{
+func (s *SqlStore) UpdateBranches(branches []storage.TransBranchStore, updates []string) (int, error) {
+	db := dbGet().Clauses(clause.OnConflict{
 		OnConstraint: "trans_branch_op_pkey",
 		DoUpdates:    clause.AssignmentColumns(updates),
 	}).Create(branches)
+	return int(db.RowsAffected), db.Error
 }
 
 func (s *SqlStore) LockGlobalSaveBranches(gid string, status string, branches []storage.TransBranchStore, branchStart int) {
diff --git a/dtmsvr/storage/store.go b/dtmsvr/storage/store.go
index 54a40f9..1a9da9c 100644
--- a/dtmsvr/storage/store.go
+++ b/dtmsvr/storage/store.go
@@ -3,11 +3,12 @@ package storage
 import (
 	"errors"
 	"time"
-
-	"gorm.io/gorm"
 )
 
+// ErrNotFound defines the query item is not found in storage implement.
 var ErrNotFound = errors.New("storage: NotFound")
+
+// ErrUniqueConflict defines the item is conflict with unique key in storage implement.
 var ErrUniqueConflict = errors.New("storage: UniqueKeyConflict")
 
 type Store interface {
@@ -16,7 +17,7 @@ type Store interface {
 	FindTransGlobalStore(gid string) *TransGlobalStore
 	ScanTransGlobalStores(position *string, limit int64) []TransGlobalStore
 	FindBranches(gid string) []TransBranchStore
-	UpdateBranchesSql(branches []TransBranchStore, updates []string) *gorm.DB
+	UpdateBranches(branches []TransBranchStore, updates []string) (int, error)
 	LockGlobalSaveBranches(gid string, status string, branches []TransBranchStore, branchStart int)
 	MaySaveNewTrans(global *TransGlobalStore, branches []TransBranchStore) error
 	ChangeGlobalStatus(global *TransGlobalStore, newStatus string, updates []string, finished bool)
diff --git a/dtmsvr/svr.go b/dtmsvr/svr.go
index f241e18..be40e1c 100644
--- a/dtmsvr/svr.go
+++ b/dtmsvr/svr.go
@@ -77,13 +77,13 @@ func updateBranchAsync() {
 			}
 		}
 		for len(updates) > 0 {
-			dbr := GetStore().UpdateBranchesSql(updates, []string{"status", "finish_time", "update_time"})
+			rowAffected, err := GetStore().UpdateBranches(updates, []string{"status", "finish_time", "update_time"})
 
-			if dbr.Error != nil {
-				logger.Errorf("async update branch status error: %v", dbr.Error)
+			if err != nil {
+				logger.Errorf("async update branch status error: %v", err)
 				time.Sleep(1 * time.Second)
 			} else {
-				logger.Infof("flushed %d branch status to db. affected: %d", len(updates), dbr.RowsAffected)
+				logger.Infof("flushed %d branch status to db. affected: %d", len(updates), rowAffected)
 				updates = []TransBranch{}
 			}
 		}
diff --git a/test/store_test.go b/test/store_test.go
index 47cd425..486b807 100644
--- a/test/store_test.go
+++ b/test/store_test.go
@@ -94,7 +94,7 @@ func TestStoreWait(t *testing.T) {
 
 func TestUpdateBranchSql(t *testing.T) {
 	if !conf.Store.IsDB() {
-		r := registry.GetStore().UpdateBranchesSql(nil, nil)
-		assert.Nil(t, r)
+		_, err := registry.GetStore().UpdateBranches(nil, nil)
+		assert.Nil(t, err)
 	}
 }