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Comment by troyk | Hacker News Reader

Am I the only one that hardly ever needs a case-sensitive query/index on string data? This is the one feature I miss from the MySQL glory days. With postgres, I use the citext type (case-insensitive text) but I guess Mongo and ReThinkDB expect you to either store the data as all lower or upper, or duplicate the field (for indexing).

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The reason we (and probably Mongo folks) do it this way is because JSON is case-sensitive, so making indexes case-insensitive wouldn't work very well.

EDIT: it looks like I misread your comment. I was talking about index/field names, while I think you were talking about field values. In this case Sam's comment below is correct -- once we add string.toLower() (which is very easy) you'll be able to do case-insensitive indexing if you like because the indexing system supports arbitrary reql expressions. If you're using rethink and this is important to you, let me (slava@rethinkdb.com) know, and we'll prioritize this.

Are the indices based on reql expressions updated incrementally?

How about making indices based on map-reduce? Would that work? Would they be updated incrementally?

Yes, indices are updated incrementally. You can currently only evaluate an index for a given row based only on that row, not on other rows. The reasons for this are pretty deep -- if you start evaluating indexes on a row based on other rows, the result becomes non-deterministic and can't easily be replicated across the cluster. Once we introduce value-based replication (as opposed to evaluation-based replication we have now) this will become possible.

Installed and played with (1.3 I think) and it looks very promising but the ability to query and order by case-insensitive text is a requirement for us. Our app deals with user provided names of people, places and things that are commonly searched and sorted.

So not using RethinkDB today, but I am 100% in love with what you guys are trying to accomplish.

I added a github issue for this -- https://github.com/rethinkdb/rethinkdb/issues/845. We should solve this soon.

If or once a string.toLower() function is added to RQL, you'll be able to have case-insensitive indexes in RethinkDB, because you can index on arbitrary functions of your rows.

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