[SOLR-2242] Get distinct count of names for a facet field

• Type: New Feature
• Status: Resolved
• Priority: Minor
• Resolution: Duplicate
• Affects Version/s: 4.0-ALPHA
• Fix Version/s: 5.2, 6.0
• Component/s: Response Writers
• Assignee: Unassigned
• Reporter: Bill Bell
• Created: 18/Nov/10 00:05
• Updated: 02/Oct/19 17:23
• Resolved: 01/Jul/15 05:00

Description

When returning facet.field=<name of field> you will get a list of matches for distinct values. This is normal behavior. This patch tells you how many distinct values you have (# of rows). Use with limit=-1 and mincount=1.

The feature is called "namedistinct". Here is an example:

Parameters:
facet.numTerms or f.<field>.facet.numTerms = true (default is false) - turn on distinct counting of terms

facet.field - the field to count the terms
It creates a new section in the facet section...

http://localhost:8983/solr/select?shards=localhost:8983/solr,localhost:7574/solr&indent=true&q=*:*&facet=true&facet.mincount=1&facet.numTerms=true&facet.limit=-1&facet.field=price

http://localhost:8983/solr/select?shards=localhost:8983/solr,localhost:7574/solr&indent=true&q=*:*&facet=true&facet.mincount=1&facet.numTerms=false&facet.limit=-1&facet.field=price

http://localhost:8983/solr/select?shards=localhost:8983/solr,localhost:7574/solr&indent=true&q=*:*&facet=true&facet.mincount=1&facet.numTerms=true&facet.limit=-1&facet.field=price

This currently only works on facet.field.

<lst name="facet_counts">
<lst name="facet_queries"/>
<lst name="facet_fields">...</lst>
<lst name="facet_numTerms">
<lst name="localhost:8983/solr/">
<int name="price">14</int>
</lst>
<lst name="localhost:8080/solr/">
<int name="price">14</int>
</lst>
</lst>
<lst name="facet_dates"/>
<lst name="facet_ranges"/>
</lst>

OR with no sharding-

<lst name="facet_numTerms">
<int name="price">14</int>
</lst>

Several people use this to get the group.field count (the # of groups).

Issue Links

• duplicates: SOLR-6968 add hyperloglog in statscomponent as an approximate count
• is blocked by: SOLR-1682 Implement CollapseComponent
• relates to: SOLR-236 Field collapsing