[refset]

I asked Rich about his thoughts on query optimizers last year (not in the context of Datomic specifically) and his only reservation was around the practical implications for the operational experience. Specifically, that database systems should always provide the means for developers to control exactly how/when/whether existing (cached) execution plans get re-optimized, otherwise query optimizers can actually be a source of greater problems than they solve, particularly for applications with extremely rapid changes in data.