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Comment by PaulHoule | Hacker News Reader

Semweb people got burned out by the stress of making new standards which means that standards haven't been updated. We've needed a SPARQL 2 for a long time but we're never going to get it.

One thing I find interesting is that description logics (OWL) seem to have stayed a backwater in a time when progress in SAT and SMT solvers has been explosive.

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> Semweb people got burned out by the stress of making new standards which means that standards haven't been updated.

True. But and also, web standards seem to have mostly been abandoned/died beyond just semantic web. I am not sure how to explain it, but there was a golden age of making inter-operable higher-level data and protocol standards, and... it's over. There much less standards-making going on. It's not just SPARQL that could use a new version, but has no standards-making activity going on.

I can't totally explain it, and would love to read someone who thinks they can.

A recent paper connects SHACL (mentioned in OP) to description logic and OWL: https://arxiv.org/abs/2108.06096 . This is a surprising link which seems to have been missed by SemWeb practitioners when SHACL was proposed.

That's a very good point re SAT/SMT. F* (https://www.fstar-lang.org/) has done truly amazing things by making use of them, and it's great to be able to get sophisticated correctness checks while doing basically non of the work.

I'm going to have to go away and think about how one could effectively leverage this in a data setting, but I'd love to hear ideas.

It doesn't have anything directly to do with SAT but I'd say the #1 deficiency in RDFS and OWL is this.

Somebody might write

   :Today :tempF 32.0 .

   :Today :tempC 0.0 .

The point of RDFS and OWL is not to force people into a straightjacket the way people think it is but rather make it possible to write a rulebox after the fact that merges data together. You might wish you could write

   :tempC rdfs:subPropertyOf :tempF .

but you can't, what you really want is to write a rule like

   ?x :tempC ?y -> ?x :tempF ?y*1.8 + 32.0

but OWL doesn't let you do that. You can do it with SPIN but SPIN never got ratified and so far all the SPIN implementations are simple fixed point iterators and don't take advantage of the large advances that have happened with production rules systems since they fell out of fashion (e.g. systems in the 1980s broke down with 10,000 rules, in 2022 1,000,000 rules is often no problem.)

Wikidata is quite usable though with SPARQL through REST. To me the biggest problem seems lack of documentation but for small scale experiments interesting stuff can be done with it (with enough caching, probably with SQL). Running my own triple store seems a lot of work though, already choosing which one to use actually

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