diff --git a/engine_table.go b/engine_table.go
index 21365dde..001d72e7 100644
--- a/engine_table.go
+++ b/engine_table.go
@@ -26,11 +26,12 @@ func (engine *Engine) tbNameWithSchema(v string) string {
 }
 
 func isSubQuery(tbName string) bool {
-	if len(tbName) <= 6 {
+	const selStr = "select"
+	if len(tbName) <= len(selStr)+1 {
 		return false
 	}
 
-	return strings.EqualFold(tbName[:5], "select") || strings.EqualFold(tbName[:6], "(select")
+	return strings.EqualFold(tbName[:len(selStr)], selStr) || strings.EqualFold(tbName[:len(selStr)+1], "("+selStr)
 }
 
 // TableName returns table name with schema prefix if has
diff --git a/session_query_test.go b/session_query_test.go
index c77695f6..7e72357f 100644
--- a/session_query_test.go
+++ b/session_query_test.go
@@ -371,15 +371,16 @@ func TestJoinWithSubQuery(t *testing.T) {
 	assert.NoError(t, err)
 	assert.EqualValues(t, 1, cnt)
 
+	tbName := testEngine.Quote(testEngine.TableName("join_with_sub_query_depart", true))
 	var querys []JoinWithSubQuery1
-	err = testEngine.Join("INNER", builder.Select("id").From(testEngine.Quote(testEngine.TableName("join_with_sub_query_depart", true))),
+	err = testEngine.Join("INNER", builder.Select("id").From(tbName),
 		"join_with_sub_query_depart.id = join_with_sub_query1.depart_id").Find(&querys)
 	assert.NoError(t, err)
 	assert.EqualValues(t, 1, len(querys))
 	assert.EqualValues(t, q, querys[0])
 
 	querys = make([]JoinWithSubQuery1, 0, 1)
-	err = testEngine.Join("INNER", "(SELECT id FROM `join_with_sub_query_depart`) join_with_sub_query_depart", "join_with_sub_query_depart.id = join_with_sub_query1.depart_id").
+	err = testEngine.Join("INNER", "(SELECT id FROM "+tbName+") join_with_sub_query_depart", "join_with_sub_query_depart.id = join_with_sub_query1.depart_id").
 		Find(&querys)
 	assert.NoError(t, err)
 	assert.EqualValues(t, 1, len(querys))