lucene-solr-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Erick Erickson <erickerick...@gmail.com>
Subject Re: Grouping and result pagination
Date Fri, 17 Mar 2017 15:07:12 GMT
I think the answer is that you have to co-locate the docs with the
same value you're grouping by on the same shard whether in SolrCloud
or not...

Hmmm: from: https://cwiki.apache.org/confluence/display/solr/Result+Grouping#ResultGrouping-DistributedResultGroupingCaveats

"group.ngroups and group.facet require that all documents in each
group must be co-located on the same shard in order for accurate
counts to be returned."

Best,
Erick

On Fri, Mar 17, 2017 at 8:00 AM, Shawn Heisey <apache@elyograg.org> wrote:
> We use pagination (start/rows) frequently with our queries.  Nothing
> unusual there.
>
> Now we have need to use grouping with a request like this, for a
> set-mode search, where only one document from each set is returned:
>
> http://idxb1.REDACTED.com:8981/solr/ncmain/lbcheck?q=*:*&group=true&group.field=set_name&group.sort=set_lead%20desc&group.limit=1&rows=50
>
> We've worked through most of the problems encountered with this idea.
> The first page of results works perfectly.
>
> The remaining problem is that I cannot seem to paginate -- set the start
> value to 50, 100, etc.  I found some information saying that
> group.ngroups=true is required for pagination, so I added that.  I have
> found that occasionally I can load page two (rows=50&start=50), but that
> *most* of the time, I can't even get page two to load, and further pages
> have never worked.  The response contains no documents.
>
> The index is distributed (sharded), but not running SolrCloud.
>
> The server where I am trying this is running a SNAPSHOT build of 4.9.  I
> haven't had an opportunity yet to try a newer version -- we don't have
> newer versions on any of the machines for this index.  I can only
> upgrade as far as 5.3, because that's as far as we can go with a
> third-party plugin we are using.
>
> I found the following issue, which says it was fixed before 4.0 was
> released:
>
> https://issues.apache.org/jira/browse/SOLR-2207
>
> Does anyone know whether pagination with grouping is expected to work,
> and if so, how to do it?
>
> Thanks,
> Shawn
>

Mime
View raw message