diff --git a/engine.go b/engine.go
index f52148a..ee98ed0 100644
--- a/engine.go
+++ b/engine.go
@@ -168,6 +168,8 @@ func (engine *Engine) SetLogger(logger interface{}) {
 		realLogger = t
 	case log.Logger:
 		realLogger = log.NewLoggerAdapter(t)
+	default:
+		panic("logger should implement either log.ContextLogger or log.Logger")
 	}
 	engine.logger = realLogger
 	engine.DB().Logger = realLogger
@@ -209,6 +211,11 @@ func (engine *Engine) SetColumnMapper(mapper names.Mapper) {
 	engine.tagParser.SetColumnMapper(mapper)
 }
 
+// SetTagIdentifier set the tag identifier
+func (engine *Engine) SetTagIdentifier(tagIdentifier string) {
+	engine.tagParser.SetIdentifier(tagIdentifier)
+}
+
 // Quote Use QuoteStr quote the string sql
 func (engine *Engine) Quote(value string) string {
 	value = strings.TrimSpace(value)
diff --git a/engine_group.go b/engine_group.go
index cdd9dd4..3e91cbd 100644
--- a/engine_group.go
+++ b/engine_group.go
@@ -167,6 +167,14 @@ func (eg *EngineGroup) SetMapper(mapper names.Mapper) {
 	}
 }
 
+// SetTagIdentifier set the tag identifier
+func (eg *EngineGroup) SetTagIdentifier(tagIdentifier string) {
+	eg.Engine.SetTagIdentifier(tagIdentifier)
+	for i := 0; i < len(eg.slaves); i++ {
+		eg.slaves[i].SetTagIdentifier(tagIdentifier)
+	}
+}
+
 // SetMaxIdleConns set the max idle connections on pool, default is 2
 func (eg *EngineGroup) SetMaxIdleConns(conns int) {
 	eg.Engine.DB().SetMaxIdleConns(conns)
diff --git a/interface.go b/interface.go
index 0fe9cbe..55162c8 100644
--- a/interface.go
+++ b/interface.go
@@ -101,6 +101,7 @@ type EngineInterface interface {
 	SetCacher(string, caches.Cacher)
 	SetConnMaxLifetime(time.Duration)
 	SetColumnMapper(names.Mapper)
+	SetTagIdentifier(string)
 	SetDefaultCacher(caches.Cacher)
 	SetLogger(logger interface{})
 	SetLogLevel(log.LogLevel)
diff --git a/session_tx.go b/session_tx.go
index 5779170..f50bbf1 100644
--- a/session_tx.go
+++ b/session_tx.go
@@ -84,3 +84,8 @@ func (session *Session) Commit() error {
 	}
 	return nil
 }
+
+// if current session is in a transaction
+func (session *Session) IsInTx() bool {
+	return !session.isAutoCommit
+}
\ No newline at end of file
diff --git a/tags/parser.go b/tags/parser.go
index a301d12..45dd6d9 100644
--- a/tags/parser.go
+++ b/tags/parser.go
@@ -63,6 +63,11 @@ func (parser *Parser) SetColumnMapper(mapper names.Mapper) {
 	parser.columnMapper = mapper
 }
 
+func (parser *Parser) SetIdentifier(identifier string) {
+	parser.ClearCaches()
+	parser.identifier = identifier
+}
+
 func (parser *Parser) ParseWithCache(v reflect.Value) (*schemas.Table, error) {
 	t := v.Type()
 	tableI, ok := parser.tableCache.Load(t)
diff --git a/tags/parser_test.go b/tags/parser_test.go
index ff304a5..c3bf805 100644
--- a/tags/parser_test.go
+++ b/tags/parser_test.go
@@ -80,3 +80,26 @@ func TestUnexportField(t *testing.T) {
 		assert.NotEqual(t, "public", col.Name)
 	}
 }
+
+func TestParseWithOtherIdentifier(t *testing.T) {
+	parser := NewParser(
+		"xorm",
+		dialects.QueryDialect("mysql"),
+		names.GonicMapper{},
+		names.SnakeMapper{},
+		caches.NewManager(),
+	)
+
+	type StructWithDBTag struct {
+		FieldFoo string `db:"foo"`
+	}
+	parser.SetIdentifier("db")
+	table, err := parser.Parse(reflect.ValueOf(new(StructWithDBTag)))
+	assert.NoError(t, err)
+	assert.EqualValues(t, "struct_with_db_tag", table.Name)
+	assert.EqualValues(t, 1, len(table.Columns()))
+
+	for _, col := range table.Columns() {
+		assert.EqualValues(t, "foo", col.Name)
+	}
+}