From fbc3fcc4afb502cc36a35b51b642fcba63539cf9 Mon Sep 17 00:00:00 2001
From: Guo Xiang Tan <tgx_world@hotmail.com>
Date: Fri, 25 Nov 2016 11:13:51 +0800
Subject: [PATCH] PERF: Make use of existing index.

---
 app/serializers/basic_group_serializer.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/app/serializers/basic_group_serializer.rb b/app/serializers/basic_group_serializer.rb
index 92d06c45419..7844e4f5121 100644
--- a/app/serializers/basic_group_serializer.rb
+++ b/app/serializers/basic_group_serializer.rb
@@ -46,6 +46,6 @@ class BasicGroupSerializer < ApplicationSerializer
   private
 
   def fetch_group_user
-    @group_user ||= (object.group_users & scope.user.group_users).first
+    @group_user ||= object.group_users.find_by(user_id: scope.user.id)
   end
 end