Crux: Bitemporal graph query db for Clojure and java

github.com

6 pointsCurrentB2 comments

Nice to see that temporal or even bitempiral database systems get developed lately more and more (but most of the time just as extensions to an existing system), thus I enjoyed reading about your native approach.

Do you store all revisions in one huge LSM- tree indexed by the transactional start- and end-times?

I'm developing one myself (already started around 2005 or 2006 by a Ph.D. student) and I'm still eager to put forth the ideas of a versioned data store :-)

> Do you store all revisions in one huge LSM- tree indexed by the transactional start- and end-times

Specifically, RocksDB uses an LSM tree whilst LMDB uses a B+ tree. You can get a feel for how Crux maintains its indexes here: https://github.com/juxt/crux/blob/master/src/crux/codec.clj#...

Crux doesn't natively track valid-to (end) times, but you can transact a Delete into the future to achieve the same logical result.

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