More Power for Datomic Datalog: Negation, Disjunction, and Range Optimizations by Stuart Halloway.
From the post:
Today’s Datomic release includes a number of enhancements to Datomic’s Datalog query language:
- Negation, via the new not and not-join clauses
- Disjunction (or) without using rules, via the new or and or-join clauses
- Required rule bindings
- Improved optimization of range predicates
Each is described below, and you can follow the examples from the mbrainz data set in Java or in Clojure.
The four hours of video in Datomic Training Videos may not be enough for you to appreciate this post but you will soon enough!
If you want a steep walk on queries, try Datomic Queries and Rules. Not for the faint of heart.
Enjoy!