# Confused about interaction between unique count and buckets **URL:** \ **Category:** Elasticsearch\ **Created:** [May 5, 2016, 2:15am UTC](https://discuss.elastic.co/t/confused-about-interaction-between-unique-count-and-buckets/49243 "2016-05-05T02:15:13Z")\ **Posts on this page:** 1\ **Showing post:** 1
**Author:** ![Fran\_Fabrizio](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/fran_fabrizio/32/9533_2.png) [@Fran\_Fabrizio](https://discuss.elastic.co/u/Fran_Fabrizio)\ **Post date:** [May 5, 2016, 2:15am UTC](https://discuss.elastic.co/t/confused-about-interaction-between-unique-count-and-buckets/49243/1 "2016-05-05T02:15:13Z")
Let's say I set my time range to be 2013-01-01 00:00:00.000 to 2013-01-31 23:59:59.999 (entire month of January 2013). Then I do a line graph visualization and keep the default y-axis setup which is a count of \_all documents in my index in that time range, it produces 1,565 hits. (just a dot at 1,565, since I haven't defined an x-axis). One of the fields in my documents is user\_id. If I then change the y-axis to do a Count of user\_id in that same time period, I get 1,565 hits. So far, nothing strange - every document has a user\_id, as I expect. Then I change the y-axis to be a Unique Count of user\_id instead, I get 488 hits. So far, so good - 488 unique users this month. If I then add a bucket - doesn't matter what kind, can be x-axis or split lines - on the scripted field term 'year' which is defined as doc['@timestamp'].getYear(), my hits go to **520**. I don't understand this - where are the extra documents coming from?? How can I have 488 unique user\_ids in my time period Jan 2013, but then have 520 unique user\_ids in time period Jan 2013 when I add year on the x-axis? "unique user\_ids by year" should not differ from "unique user\_ids" when the time period is just Jan 2013! This only seems to affect Unique Count. If I do the original plain count (1,565) and then add the 'year' sub-bucket, I still get 1,565, which is what I expect. So what am I not understanding about the interplay between Unique Count and buckets? --- _[View the full topic](https://discuss.elastic.co/t/confused-about-interaction-between-unique-count-and-buckets/49243)._