# Scrolling / sorting

**URL:** <https://discuss.elastic.co/t/scrolling-sorting/4907>\
**Category:** Elasticsearch\
**Created:** [July 20, 2011, 12:27pm UTC](https://discuss.elastic.co/t/scrolling-sorting/4907 "2011-07-20T12:27:41Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![Jan\_Kriesten](https://avatars.discourse-cdn.com/v4/letter/j/43a26b/32.png) [@Jan\_Kriesten](https://discuss.elastic.co/u/Jan_Kriesten)\
**Post date:** [July 20, 2011, 12:27pm UTC](https://discuss.elastic.co/t/scrolling-sorting/4907/1 "2011-07-20T12:27:41Z")

</div>

Hi,

I've got the following code to build up a scrolling search with  
elasticsearch:

public ActionFuture execute(final Client client) {  
final SearchRequest request = Requests.searchRequest();  
request.searchType(SearchType.SCAN);  
request.scroll(new TimeValue(timeout));  
final SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();  
sourceBuilder.query(query);  
sourceBuilder.from(0);  
sourceBuilder.size(scrollSize);  
sourceBuilder.explain(true);  
sourceBuilder.sort(sortField, SortOrder.ASC);  
request.source(sourceBuilder);

return client.search(request);  
}

There are two problems I encounter:

First, instead of returning 'scrollSize' elements I always get  
'scrollSize \* 3' elements with each scroll request. Did I miss  
something here?

Second, sorting is completely ignored with this query. What am I doing  
wrong?

Thanks for any hints!

Best regards, --- Jan.

---

<div class="post-metadata">

**Author:** ![Clinton\_Gormley](https://avatars.discourse-cdn.com/v4/letter/c/50afbb/32.png) [@Clinton\_Gormley](https://discuss.elastic.co/u/Clinton_Gormley)\
**Post date:** [July 20, 2011, 12:36pm UTC](https://discuss.elastic.co/t/scrolling-sorting/4907/2 "2011-07-20T12:36:03Z")

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Hi Jan

> First, instead of returning 'scrollSize' elements I always get  
> 'scrollSize \* 3' elements with each scroll request. Did I miss  
> something here?
> 
> Second, sorting is completely ignored with this query. What am I doing  
> wrong?

Nothing - it is working exactly as expected. The scan search\_type is  
intended for pulling large numbers of docs out of ES efficiently. It is  
not intended for returning search results to users.

Each scroll request receives a maximum of scrollSize \* $no\_of\_shards  
results (until each shard runs out of more results).

And sorting is ignored for scan requests.

clint

---

<div class="post-metadata">

**Author:** ![Jan\_Kriesten](https://avatars.discourse-cdn.com/v4/letter/j/43a26b/32.png) [@Jan\_Kriesten](https://discuss.elastic.co/u/Jan_Kriesten)\
**Post date:** [July 20, 2011, 2:09pm UTC](https://discuss.elastic.co/t/scrolling-sorting/4907/3 "2011-07-20T14:09:56Z")

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Hi Clint,

> Each scroll request receives a maximum of scrollSize \* $no\_of\_shards  
> results (until each shard runs out of more results).

is that the expected behavior for SearchSourceBuilder as well when  
setting from/size? Cause setting size to 10 also results in 30 hits.

Best regards, --- Jan.

---

<div class="post-metadata">

**Author:** ![Clinton\_Gormley](https://avatars.discourse-cdn.com/v4/letter/c/50afbb/32.png) [@Clinton\_Gormley](https://discuss.elastic.co/u/Clinton_Gormley)\
**Post date:** [July 20, 2011, 2:20pm UTC](https://discuss.elastic.co/t/scrolling-sorting/4907/4 "2011-07-20T14:20:01Z")

</div>

Hi Jan

> > Each scroll request receives a maximum of scrollSize \* $no\_of\_shards  
> > results (until each shard runs out of more results).
> 
> is that the expected behavior for SearchSourceBuilder as well when  
> setting from/size? Cause setting size to 10 also results in 30 hits.

I can only speak for the REST interface, don't know the Java API.

But for search\_type = scan, you will always get back a maximum of  
size x shards results on each scroll request. (size is, by default, 10)

So if you had 5 shards, you would get back a max of 50 results at a  
time, until each shard starts running out of results.

You know that you have pulled all results when you get zero results back

clint

---

<div class="post-metadata">

**Author:** ![Jan\_Kriesten](https://avatars.discourse-cdn.com/v4/letter/j/43a26b/32.png) [@Jan\_Kriesten](https://discuss.elastic.co/u/Jan_Kriesten)\
**Post date:** [July 20, 2011, 2:24pm UTC](https://discuss.elastic.co/t/scrolling-sorting/4907/5 "2011-07-20T14:24:31Z")

</div>

Hi Clinton,

> But for search\_type = scan, you will always get back a maximum of  
> size x shards results on each scroll request. (size is, by default, 10)

I meant SearchType.DFS\_QUERY\_AND\_FETCH is also returning size x shards -  
is that expected?

Best regards, --- Jan.

---

<div class="post-metadata">

**Author:** ![Clinton\_Gormley](https://avatars.discourse-cdn.com/v4/letter/c/50afbb/32.png) [@Clinton\_Gormley](https://discuss.elastic.co/u/Clinton_Gormley)\
**Post date:** [July 20, 2011, 2:30pm UTC](https://discuss.elastic.co/t/scrolling-sorting/4907/6 "2011-07-20T14:30:16Z")

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Hi Jan

> > But for search\_type = scan, you will always get back a maximum of  
> > size x shards results on each scroll request. (size is, by default, 10)
> 
> I meant SearchType.DFS\_QUERY\_AND\_FETCH is also returning size x shards -  
> is that expected?

Ah right. Then yes, that is expected:

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clint

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [July 6, 2017, 4:00am UTC](https://discuss.elastic.co/t/scrolling-sorting/4907/7 "2017-07-06T04:00:03Z")

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