Hi All, While thinking about SOLR-1131, something important just came to mind. If we allow poly fields to add fields to the schema (be it via dynamic fields, or explicit field decls, either way), then we introduce a disconnect between the existing XML schema, and the runtime schema instance. To my knowledge there is no write-back/flush back for changes made to the schema at run-time, and what's loaded on startup (correct me if I'm wrong).
Flushing back changes is probably _not_ a good idea for (at least) the following reasons: * someone may have put comments into the schema.xml file that helps them to understand the fields/etc. in the file -- the flush back operation would then have to deal with these, and dealing with formatting, etc., would be a hassle. * there may be existing tools (e.g., Schema editors, etc.) that may be developed, and allowing a SOLR instance to modify a schema file and flush it back may interfere with someone using an editor on their schema (though doing so at runtime whether you're using a tool or vi is not a good idea either way) That said, I'm wondering what the right compromise is here? My instinct says that PolyFields should _only_ be able to deal with fields that have already been recorded in the schema.xml file (yes, this is limiting). That's the only way to truly keep the schema and its run-time instance in sync, while preserving all the manual curation activities that have occurred in the schema and not stepping on any toes. Also, I'm (ack!) now leaning towards dynamic fields as a flexible method to do this (so long as they are pre-declared in the schema.xml file explicitly) -- that way you don't have to create (n+10) * m fields for a 10-dimensional point that's stored as well as indexed. So based, on this, and based on my knowledge of the existing patches, if we added a check that ensured that the dynamic field(s) already be declared in the schema at startup, then I think all is well. Thoughts? Cheers, Chris ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Chris Mattmann, Ph.D. Senior Computer Scientist NASA Jet Propulsion Laboratory Pasadena, CA 91109 USA Office: 171-266B, Mailstop: 171-246 Email: chris.mattm...@jpl.nasa.gov WWW: http://sunset.usc.edu/~mattmann/ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Adjunct Assistant Professor, Computer Science Department University of Southern California, Los Angeles, CA 90089 USA ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
