Thanks for taking time to write a detailed answer. We use Solr to both store our data and to perform aggregations, using faceting or streaming expressions. When required analysis is too complex to do in Solr, we export large query results from Solr to a more capable analysis tool.
So I guess all fields need to be docValues="true", because export handler and streaming both require fields to have docValues, and even if I won't use a field in queries or facets, it should be in available to read in result set. Fields that won't be searched or faceted can be (indexed=false stored=false docValues=true) right? --uyilmaz On Mon, 19 Oct 2020 14:14:27 -0400 Michael Gibney <mich...@michaelgibney.net> wrote: > As you've observed, it is indeed possible to facet on fields with > docValues=true, indexed=false; but in almost all cases you should > probably set indexed=true. 1. for distributed facet count refinement, > the "indexed" approach is used to look up counts by value; 2. assuming > you're wanting to do something usual, e.g. allow users to apply > filters based on facet counts, the filter application would use the > "indexed" approach as well. Where indexed=false, if either filtering > or distributed refinement is attempted, I'm not 100% sure what > happens. It might fail, or lead to inconsistent results, or attempt to > look up results via the equivalent of a "table scan" over docValues (I > think the last of these is what actually happens, fwiw) ... but none > of these options is likely desirable. > > Michael > > On Mon, Oct 19, 2020 at 1:42 PM uyilmaz <uyil...@vivaldi.net.invalid> wrote: > > > > Thanks! This also contributed to my confusion: > > > > https://lucene.apache.org/solr/guide/8_4/faceting.html#field-value-faceting-parameters > > > > "If you want Solr to perform both analysis (for searching) and faceting on > > the full literal strings, use the copyField directive in your Schema to > > create two versions of the field: one Text and one String. Make sure both > > are indexed="true"." > > > > On Mon, 19 Oct 2020 13:08:00 -0400 > > Alexandre Rafalovitch <arafa...@gmail.com> wrote: > > > > > I think this is all explained quite well in the Ref Guide: > > > https://lucene.apache.org/solr/guide/8_6/docvalues.html > > > > > > DocValues is a different way to index/store values. Faceting is a > > > primary use case where docValues are better than what 'indexed=true' > > > gives you. > > > > > > Regards, > > > Alex. > > > > > > On Mon, 19 Oct 2020 at 12:51, uyilmaz <uyil...@vivaldi.net.invalid> wrote: > > > > > > > > > > > > Hey all, > > > > > > > > From my little experiments, I see that (if I didn't make a stupid > > > > mistake) we can facet on fields marked as both indexed and stored being > > > > false: > > > > > > > > <field name="nonStorednonIndexedDocvalues" type="string" > > > > indexed="false" stored="false" docValues="true"/> > > > > > > > > I'm suprised by this, I thought I would need to index it. Can you > > > > confirm this? > > > > > > > > Regards > > > > > > > > -- > > > > uyilmaz <uyil...@vivaldi.net> > > > > > > -- > > uyilmaz <uyil...@vivaldi.net> -- uyilmaz <uyil...@vivaldi.net>
