diff --git a/client/dtmcli/consts.go b/client/dtmcli/consts.go
index bb87a15..a0aab2c 100644
--- a/client/dtmcli/consts.go
+++ b/client/dtmcli/consts.go
@@ -35,8 +35,8 @@ const (
 	DBTypeMysql = dtmimp.DBTypeMysql
 	// DBTypePostgres const for driver postgres
 	DBTypePostgres = dtmimp.DBTypePostgres
-	// DBTypeSqlServer const for driver SqlServer
-	DBTypeSqlServer = dtmimp.DBTypeSqlServer
+	// DBTypeSQLServer const for driver SQLServer
+	DBTypeSQLServer = dtmimp.DBTypeSQLServer
 )
 
 // MapSuccess HTTP result of SUCCESS
diff --git a/client/dtmcli/dtmimp/consts.go b/client/dtmcli/dtmimp/consts.go
index 036e6dc..362e8a9 100644
--- a/client/dtmcli/dtmimp/consts.go
+++ b/client/dtmcli/dtmimp/consts.go
@@ -36,8 +36,8 @@ const (
 	DBTypeMysql = "mysql"
 	// DBTypePostgres const for driver postgres
 	DBTypePostgres = "postgres"
-	// DBTypeSqlServer const for driver SqlServer
-	DBTypeSqlServer = "sqlserver"
+	// DBTypeSQLServer const for driver SQLServer
+	DBTypeSQLServer = "sqlserver"
 	// DBTypeRedis const for driver redis
 	DBTypeRedis = "redis"
 	// Jrpc const for json-rpc
diff --git a/client/dtmcli/dtmimp/db_special.go b/client/dtmcli/dtmimp/db_special.go
index 2f0c6d4..5a2bb83 100644
--- a/client/dtmcli/dtmimp/db_special.go
+++ b/client/dtmcli/dtmimp/db_special.go
@@ -96,7 +96,7 @@ func (*sqlserverDBSpecial) GetXaSQL(command string, xid string) string {
 	return ""
 }
 func init() {
-	dbSpecials[DBTypeSqlServer] = &sqlserverDBSpecial{}
+	dbSpecials[DBTypeSQLServer] = &sqlserverDBSpecial{}
 }
 
 // GetDBSpecial get DBSpecial for currentDBType
diff --git a/client/dtmcli/dtmimp/utils.go b/client/dtmcli/dtmimp/utils.go
index 223ed39..e62234f 100644
--- a/client/dtmcli/dtmimp/utils.go
+++ b/client/dtmcli/dtmimp/utils.go
@@ -229,13 +229,13 @@ func GetDsn(conf DBConf) string {
 		"postgres": fmt.Sprintf("host=%s user=%s password=%s dbname='%s' search_path=%s port=%d sslmode=disable",
 			host, conf.User, conf.Password, conf.Db, conf.Schema, conf.Port),
 		// sqlserver://sa:mypass@localhost:1234?database=master&connection+timeout=30
-		"sqlserver": getSqlServerConnectionString(&conf, &host),
+		"sqlserver": getSQLServerConnectionString(&conf, &host),
 	}[driver]
 	PanicIf(dsn == "", fmt.Errorf("unknow driver: %s", driver))
 	return dsn
 }
 
-func getSqlServerConnectionString(conf *DBConf, host *string) string {
+func getSQLServerConnectionString(conf *DBConf, host *string) string {
 	query := url.Values{}
 	query.Add("database", conf.Db)
 	u := &url.URL{
diff --git a/dtmsvr/config/config.go b/dtmsvr/config/config.go
index e9ba1e6..30f0115 100644
--- a/dtmsvr/config/config.go
+++ b/dtmsvr/config/config.go
@@ -20,8 +20,8 @@ const (
 	BoltDb = "boltdb"
 	// Postgres is postgres driver
 	Postgres = "postgres"
-	// SqlServer is SQL Server driver
-	SqlServer = "sqlserver"
+	// SQLServer is SQL Server driver
+	SQLServer = "sqlserver"
 )
 
 // MicroService config type for microservice based grpc
@@ -67,7 +67,7 @@ type Store struct {
 
 // IsDB checks config driver is mysql or postgres
 func (s *Store) IsDB() bool {
-	return s.Driver == dtmcli.DBTypeMysql || s.Driver == dtmcli.DBTypePostgres || s.Driver == dtmcli.DBTypeSqlServer
+	return s.Driver == dtmcli.DBTypeMysql || s.Driver == dtmcli.DBTypePostgres || s.Driver == dtmcli.DBTypeSQLServer
 }
 
 // GetDBConf returns db conf info
diff --git a/dtmsvr/storage/sql/sql.go b/dtmsvr/storage/sql/sql.go
index 8ae53a4..569c966 100644
--- a/dtmsvr/storage/sql/sql.go
+++ b/dtmsvr/storage/sql/sql.go
@@ -107,7 +107,7 @@ func (s *Store) LockGlobalSaveBranches(gid string, status string, branches []sto
 		g := &storage.TransGlobalStore{}
 		var dbr *gorm.DB
 		// sqlserver sql should be: SELECT * FROM "trans_global" with(RowLock,UpdLock) ,but gorm generates "FOR UPDATE" at the back, raw sql instead.
-		if conf.Store.Driver == config.SqlServer {
+		if conf.Store.Driver == config.SQLServer {
 			dbr = tx.Raw("SELECT * FROM trans_global with(RowLock,UpdLock) WHERE gid=? and status=? ORDER BY id OFFSET 0 ROW FETCH NEXT 1 ROWS ONLY ", gid, status).First(g)
 		} else {
 			dbr = tx.Clauses(clause.Locking{Strength: "UPDATE"}).Model(g).Where("gid=? and status=?", gid, status).First(g)
@@ -169,16 +169,10 @@ func (s *Store) LockOneGlobalTrans(expireIn time.Duration) *storage.TransGlobalS
 	nextCronTime := getTimeStr(int64(expireIn / time.Second))
 	where := fmt.Sprintf(`next_cron_time < '%s' and status in ('prepared', 'aborting', 'submitted')`, nextCronTime)
 
-	order := map[string]string{
-		dtmimp.DBTypeMysql:     `order by rand()`,
-		dtmimp.DBTypePostgres:  `order by random()`,
-		dtmimp.DBTypeSqlServer: `order by rand()`,
-	}[conf.Store.Driver]
-
 	ssql := map[string]string{
-		dtmimp.DBTypeMysql:     fmt.Sprintf(`select id from trans_global where %s %s limit 1`, where, order),
-		dtmimp.DBTypePostgres:  fmt.Sprintf(`select id from trans_global where %s %s limit 1`, where, order),
-		dtmimp.DBTypeSqlServer: fmt.Sprintf(`select top 1 id from trans_global where %s %s`, where, order),
+		dtmimp.DBTypeMysql:     fmt.Sprintf(`select id from trans_global where %s order by rand() limit 1`, where),
+		dtmimp.DBTypePostgres:  fmt.Sprintf(`select id from trans_global where %s order by random() limit 1`, where),
+		dtmimp.DBTypeSQLServer: fmt.Sprintf(`select top 1 id from trans_global where %s order by rand()`, where),
 	}[conf.Store.Driver]
 	var id int64
 	err := db.ToSQLDB().QueryRow(ssql).Scan(&id)
@@ -211,7 +205,7 @@ func (s *Store) ResetCronTime(after time.Duration, limit int64) (succeedCount in
 	where := map[string]string{
 		dtmimp.DBTypeMysql:     fmt.Sprintf(`next_cron_time > '%s' and status in ('prepared', 'aborting', 'submitted') limit %d`, nextCronTime, limit),
 		dtmimp.DBTypePostgres:  fmt.Sprintf(`id in (select id from trans_global where next_cron_time > '%s' and status in ('prepared', 'aborting', 'submitted') limit %d )`, nextCronTime, limit),
-		dtmimp.DBTypeSqlServer: fmt.Sprintf(`id in (select top %d id from trans_global where next_cron_time > '%s' and status in ('prepared', 'aborting', 'submitted') )`, limit, nextCronTime),
+		dtmimp.DBTypeSQLServer: fmt.Sprintf(`id in (select top %d id from trans_global where next_cron_time > '%s' and status in ('prepared', 'aborting', 'submitted') )`, limit, nextCronTime),
 	}[conf.Store.Driver]
 
 	sql := fmt.Sprintf(`UPDATE trans_global SET update_time='%s',next_cron_time='%s' WHERE %s`,
@@ -329,7 +323,7 @@ func wrapError(err error) error {
 }
 
 func getTimeStr(afterSecond int64) string {
-	if conf.Store.Driver == config.SqlServer {
+	if conf.Store.Driver == config.SQLServer {
 		return dtmutil.GetNextTime(afterSecond).Format(time.RFC3339)
 	}
 	return dtmutil.GetNextTime(afterSecond).Format("2006-01-02 15:04:05")
diff --git a/dtmutil/db.go b/dtmutil/db.go
index 4237ccf..db09ab9 100644
--- a/dtmutil/db.go
+++ b/dtmutil/db.go
@@ -30,7 +30,7 @@ func getGormDialetor(driver string, dsn string) gorm.Dialector {
 	if driver == dtmcli.DBTypePostgres {
 		return postgres.Open(dsn)
 	}
-	if driver == dtmcli.DBTypeSqlServer {
+	if driver == dtmcli.DBTypeSQLServer {
 		return sqlserver.Open(dsn)
 	}
 	dtmimp.PanicIf(driver != dtmcli.DBTypeMysql, fmt.Errorf("unknown driver: %s", driver))
diff --git a/test/main_test.go b/test/main_test.go
index 5b2c1ce..9568992 100644
--- a/test/main_test.go
+++ b/test/main_test.go
@@ -53,7 +53,7 @@ func TestMain(m *testing.M) {
 		conf.Store.User = ""
 		conf.Store.Password = ""
 		conf.Store.Port = 6379
-	} else if tenv == config.SqlServer {
+	} else if tenv == config.SQLServer {
 		conf.Store.User = "sa"
 		conf.Store.Password = "p@ssw0rd"
 		conf.Store.Port = 1433