Json facet on string fields run lot slower than on numeric fields. Try and
see if you can represent studentid as a numeric field.
On Apr 30, 2017 1:19 PM, "Mikhail Ibraheem" <mikhail.ibrah...@oracle.com>
wrote:
> Hi,
>
> I am trying to do aggregation with JSON faceting but performance is very
> bad for one of the requests:
>
> json.facet={
>
> studentId:{
>
> type:terms,
>
> limit:-1,
>
> field:"studentId",
>
> facet:{
>
> x:"sum(grades)"
>
> }
>
> }
>
> }
>
>
>
> This request finishes in 250 seconds, and we can't paginate for this
> service for functional reason so we have to use limit:-1, and the
> cardinality of the studentId is 7500.
>
>
>
> If I try the same with flat facet it finishes in 3 seconds :
> stats=true&facet=true&stats.field={!tag=piv1
> sum=true}grades&facet.pivot={!stats=piv1}studentId
>
>
>
> We are hoping to use one approach json or flat for all our services. JSON
> facet performance is better for many case.
>
>
>
> Please advise on why the performance for this is so bad and if we can
> improve it. Also what is the default algorithm used for json facet.
>
>
>
> Thanks
>
> Mikhail
>
