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MillenniumDB: Property graph and RDF engine, still in development

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Re: MillenniumDB: Property graph and RDF engine, still in development

#31

Post by bawolff »

j-pb wrote: post #13

These guys write really great papers! We implemented a simplified version of their ring index for our data space ( https://github.com/triblespace/tribles-rust/blob/master/src/... ), and it's a really simple and cool idea once you wrap your head around it. Funnily enough, we build this even before the paper was officially published, because we found a preprint on one of the authors blogs. The idea itself was published…

The whole ring index thing is one of the more fascinating ideas i've read about (i didnt realize milleniumDB was same authors). Sent me down a whole rabbit hole of learning about succinct data structures and burrows-wheeler transform.

Sometimes you encounter a computer science idea that just sounds like pure magic.

Re: MillenniumDB: Property graph and RDF engine, still in development

#32

Post by bawolff »

sunshine-o wrote: post #27

I got very interested in RDF about 20-25 years ago. Obviously it did not really succeeded but it seems some industries invested a lot into the tech and it is still around. Especially since AWS built a service around it. I am really curious, what are the top use cases for it today?

I think wikidata (https://query.wikidata.org) is one of the more well known ones.

Re: MillenniumDB: Property graph and RDF engine, still in development

#33

Post by PaulHoule »

kendallgclark wrote: post #28
PaulHoule wrote: post #25

Earlier quoted context omitted.

Personally I thought Stardog was trash, but if I'd had different requirements I might be happy with it. The trouble w/ OWL as I see it (talked about in that TR) is that people don't really want "first order logic", but they want "first order logic + arithmetic" which is a nightmare that Kurt Godel warned you about. (That ISO 20022 which that TR is related to is about the financial domain which is all about arithmetic…

You seem nice.

Sorry for the negativity Kendall but the semweb didn't return the love that I gave it. I did hundreds of sales calls that went nowhere, but my phone kept ringing for people who wanted me to work on neural nets.

Re: MillenniumDB: Property graph and RDF engine, still in development

#34

Post by UltraSane »

FjordWarden wrote: post #11
smarx007 wrote: post #9

I think if someone is just trying out RDF, it is better to start with Apache Jena/Fuseki or Eclipse RDF4J. Maybe https://github.com/oxigraph/oxigraph if you like to live dangerously (i.e. to use pre-1.0 DBMSs). Use of other systems involves factoring tradeoffs and considerations that are probably not the best for the newcomers. For example, qLever mentioned here is good in query performance and relative disk use but…

If you expect Jena to be more battle-tested because it is older, forget it, if the process is killed by a unexpected shutdown or some other reason it results in data corruption. At least this was my experience a few years ago. I found graph databases a beguiling idea when I first learned about them, and this is a welcome addition, but I've since temperated my excitement. They are not as flexible and universal a modal…

Property graphs map to relational databases pretty well. Using Neo4j's terminology

table name -> node label

table row -> node

table column -> node property

The result of a query is a sub-graph and is very composable.

Re: MillenniumDB: Property graph and RDF engine, still in development

#35

Post by Karrot_Kream »

hobofan wrote: post #14
smarx007 wrote: post #9

I think if someone is just trying out RDF, it is better to start with Apache Jena/Fuseki or Eclipse RDF4J. Maybe https://github.com/oxigraph/oxigraph if you like to live dangerously (i.e. to use pre-1.0 DBMSs). Use of other systems involves factoring tradeoffs and considerations that are probably not the best for the newcomers. For example, qLever mentioned here is good in query performance and relative disk use but…

As someone that has built production systems with Oxigraph (and a bit less with Jena), I'd recommend Oxigraph over Jena any day. Especially if you have you are working with a Rust-based tech stack. You can save so much time and headache based on less operational complexity and the architectural options it opens up. If you only reinvest part of that into building a framework for versioning/backups, etc. you'll have a…

Interesting. Do you think RDF is easier to work with in Rust's ecosystem than Java's ecosystem as a whole in your opinion? I've only touched Jena and worked with Java and Go systems with RDF.

Re: MillenniumDB: Property graph and RDF engine, still in development

#36

Post by UltraSane »

kendallgclark wrote: post #28
PaulHoule wrote: post #25

Earlier quoted context omitted.

Personally I thought Stardog was trash, but if I'd had different requirements I might be happy with it. The trouble w/ OWL as I see it (talked about in that TR) is that people don't really want "first order logic", but they want "first order logic + arithmetic" which is a nightmare that Kurt Godel warned you about. (That ISO 20022 which that TR is related to is about the financial domain which is all about arithmetic…

You seem nice.

You mean brutally honest.

Re: MillenniumDB: Property graph and RDF engine, still in development

#37

Post by UltraSane »

jerven wrote: post #10

MilleniumDB is an interesting engine, as is Qlever mentioned in other comments. I think both are good candidates at making RDF graphs one or two orders of magnitude cheaper to host as sparql endpoints. Both seem to have arrived at the stage of transitioning from research to production code. Very exiting for those of us providing our data in RDF and exposing Sparql. AWs Neptune analytics is also very interesting, allo…

It seems like writing Cypher to query RDF would be hard.

Re: MillenniumDB: Property graph and RDF engine, still in development

#38

Post by kendallgclark »

PaulHoule wrote: post #33
kendallgclark wrote: post #28

Earlier quoted context omitted.

You seem nice.

Sorry for the negativity Kendall but the semweb didn't return the love that I gave it. I did hundreds of sales calls that went nowhere, but my phone kept ringing for people who wanted me to work on neural nets.

That’s tough. Not sure what that has to do with Stardog. Biggest companies in the world rely on it daily and you say it’s trash. I couldn’t find an email from you using it since 2013. I guess we figured something out. NNs are cool too; at last count we use half a dozen different ones including GNNs… NeSy is hot and I can hardly read a paper these days that doesn’t talk about triples.

Re: MillenniumDB: Property graph and RDF engine, still in development

#39

Post by PaulHoule »

kendallgclark wrote: post #38
PaulHoule wrote: post #33

Earlier quoted context omitted.

Sorry for the negativity Kendall but the semweb didn't return the love that I gave it. I did hundreds of sales calls that went nowhere, but my phone kept ringing for people who wanted me to work on neural nets.

That’s tough. Not sure what that has to do with Stardog. Biggest companies in the world rely on it daily and you say it’s trash. I couldn’t find an email from you using it since 2013. I guess we figured something out. NNs are cool too; at last count we use half a dozen different ones including GNNs… NeSy is hot and I can hardly read a paper these days that doesn’t talk about triples.

(1) I'll grant it was a long time ago. Things could have changed a lot.

(2) It's generic that a new database comes out, gets hyped, but turns out to be "trash" when you try to use it. If a new database was actually good that would be exceptional. (Probably in 2013 it satisfied somebody's requirements but the hype for Stardog in 2013 seemed to be entirely out of line with what I needed for the project I was doing at the time)

I thought Postgres was trash in 2001 and called it CrashGreSlow, now I swear by it. Early on people were making big claims for it that were not substantiated but people did the hard work over a long time to make it great.

I thought mongodb was trash when it came out, then I worked for a place that used it despite the engineers believing it was trash and begging me not to use it for a spike prototype. It never got better. Now it is common knowledge that mongodb is trash.

(3) Maybe it's not fair but I was hurt by the experience, my wife was furious at the balance I'd run up on the HELOC chasing my Moby Dick. As an applications programmer who was accustomed to getting things right I had a terrible opinion of most of the luminaries in the semantic web field at the time many of whom were shipping code that was academic quality at best.

Re: MillenniumDB: Property graph and RDF engine, still in development

#40

Post by AtlasBarfed »

UltraSane wrote: post #34
FjordWarden wrote: post #11

Earlier quoted context omitted.

If you expect Jena to be more battle-tested because it is older, forget it, if the process is killed by a unexpected shutdown or some other reason it results in data corruption. At least this was my experience a few years ago. I found graph databases a beguiling idea when I first learned about them, and this is a welcome addition, but I've since temperated my excitement. They are not as flexible and universal a modal…

Property graphs map to relational databases pretty well. Using Neo4j's terminology table name -> node label table row -> node table column -> node property The result of a query is a sub-graph and is very composable.

I think it maps much better to document databases.

Nodes are just documents.

You just need to slap on a relations document type for the graph edges, and to store edge properties

I was close to finishing at least version 1.0 of a document/graph database on top of Cassandra and dynamodb.

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