bug fix

linucb/views/collect_data.py

@@ -162,7 +162,8 @@ class CollectData(object):
                                 tag_list = list()
                                 click_topic_tag_list = list()
                                 collection_tag_sql_query_results = TopicTag.objects.using(settings.SLAVE_DB_NAME).filter(topic_id=topic_id).values_list("tag_id","is_online","is_collection")
-                                for tag_id,is_online,is_collection in collection_tag_sql_query_results:
+                                if len(collection_tag_sql_query_results)>0:
+                                 for tag_id,is_online,is_collection in collection_tag_sql_query_results:
                                     if is_online and is_collection == 1:
                                         click_topic_tag_list.append(tag_id)