BTW, I don't think Solr/SolrCloud *internally* does something that would trigger the ID field to be in the fieldCache and thus benefit from docValues. If I'm wrong, I'd like to know. It would take sorting on the field or using one of a variety of features that tend to advertise docValues being desirable.
I wish the FieldCache was explicitly opt-in. Hossman made inroads into this by adding a feature where you can disable it on a per-field basis but I think we overall forgot to set this as a new default in a major release. ~ David Smiley Apache Lucene/Solr Search Developer http://www.linkedin.com/in/davidwsmiley On Fri, Dec 23, 2022 at 11:21 AM Bram Van Dam <bram.van...@intix.eu> wrote: > Greetings, > > We ran into a pretty hairy problem on 7.7. TL;DR; we had to enable > docValues on the unique key field in a large SolrCloud instance, without > being able to reindex old data. > > This kind of worked, by specifying different config sets in > core.properties for different shards, where new shards would get the > schema from ZK and newly indexed data would (correctly) use DocValues, > while old data in older shards remained unaffected. > > This broke when old data was modified: Solr would use the new schema for > the updates, and the index would get corrupted because documents with > and without docValues would be mixed in the same segment in the same > core, which resulted in errors when retrieving the documents (curiously, > not when merging the segments?). > > The linked patch, by my colleague Danny, allows Solr to use the correct > schema when updating data in these old shards (based on the > configuration in core.properties). > > We realize that this is a pretty ugly hack for a rather specific > problem. But at the same time, Solr allows for different configSets to > be specified for different cores, and this patch sort of improves > support for that. > > This applies cleanly on (the admittedly ancient) branch_7_7. All tests > are green, precommit checks are OK. > > If there is any interest in this patch, we might be able to look in to > making it available on master or branch_9x. > > https://foss.intix.eu/solr/2022-12-solr-schema.patch > > Any feedback is of course greatly appreciated. > > Thanks, and season's greetings! > > - Bram > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@solr.apache.org > For additional commands, e-mail: dev-h...@solr.apache.org > >
