We should rather work towards better documentation and perhaps tooling on what schema updates are "safe" without reindexing. It is NOT safe to change a field's type (or add docValues in-flight). Would be nice if the user is alerted about this when deploying the new schema. Masking the issue by alllowing mixed schema across the cluster is probably not a good idea. While it COULD work for some use cases, other kind of schema differences will fail loudly further down the road.
Jan > 3. jan. 2023 kl. 03:54 skrev Shawn Heisey <apa...@elyograg.org>: > > On 1/2/23 02:29, Bram Van Dam wrote: >> Mixtures of old and new schemas are not supported here. In fact, this patch >> was made specifically to prevent that: it allows Solr Cloud to always use >> the "old" schema for old shards. Simply put the configSet in ZK and refer to >> it in core.properties. >> We noticed that once documents with multiple schemas got merged into a >> single segment, things would break horribly (in this case because some docs >> had DocValues on the unique field and others did not). > > Some features like grouping appear to require docValues to work at all. If > some shards have docValues and some don't, those features are likely to break > horribly, or at least not return expected results. > > For everything to work right, whenever a schema change is made that involves > docValues at all, a complete index wipe followed by a full reindex is usually > required by Lucene. Without this patch, the breakage when the reindex is not > done is a very loud Exception. I fear that this patch would result in > incorrect results being returned without an error for features that use > docValues, like grouping, sorting, facets, etc. > > But I do not know enough about the Lucene internals to know if my fear is > justified. > > Thanks, > Shawn > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@solr.apache.org > For additional commands, e-mail: dev-h...@solr.apache.org > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@solr.apache.org For additional commands, e-mail: dev-h...@solr.apache.org
