LogicBlox – Datalog REPL Tutorial
developer.logicblox.com
developer.logicblox.com
Next-Paradigm Programming Languages: What Will They Look Like and What Changes Will They Bring?
https://arxiv.org/abs/1905.00402
(In addition to seeing it cited by the Souffle paper I mentioned in a sibling comment.)
It was an interesting paper that gives a flavor for logic / declarative programming, e.g. how to reason about performance, and the problem of tiny changes causing asymptotic performance differences (a problem that SQL shares).
But I think it is mistitled -- it really is about a particular problem domain and is not about programming languages in general.
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'
addblock 'cost[icecream] = c ->
string(icecream), int(c).'
No active workspace
https://souffle-lang.github.io/
Some benchmarks here showing it beating a lot of other engines:
https://souffle-lang.github.io/pdf/cc.pdf (this paper also cites LogixBlox)
They translate datalog into a straightforward relational bytecode, then use Futamura projections to compile that bytecode into a template-heavy "monolithic" C++ program.
As far as I remember one of use of C++ templates is to specialize for different sizes of tuples, so fast assembly is generated for particular queries/facts. They are doing at least 3 nontrivial transformations, and the last step really leverages C++.
The generated C++ is also multi-threaded, which is a big win.
I watched a talk on Rust where Niko M said he prototyped the new borrow checker with Souffle I believe. It's somewhere on YouTube.
"I'm casually involved,"
Humble understatement of the year! Thank you for your work!
Probably the most popular implementation is datomic and its free variants. Which has a lot of convenience to it as you can embed custom java functions.
It's not datalog but cypher has a lot of amazing ideas like easily combining algorithms to potentially recursive relationship queries, eg, "Give me the all shortest paths between these two peoples where there's at most 6 hops" -> allShortestPaths((n1:Person)-[*..6]->(n2:Person)) .
We don't have online REPL just yet but Nextjournal is pretty great if you want to play through the tutorials interactively [1]. The other unique angle is that Crux gives you "bitemporal" Datalog queries. Oh and the MIT license :)