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Datomic is Free

blog.datomic.com

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Re: Datomic is Free

#211

Post by thewataccount »

electroly wrote: post #195
thewataccount wrote: post #192

Earlier quoted context omitted.

How's it been for production? Would you recommend using it, or would it be better to go with a safer option?

We've never had any issue with it on a typical three-node install in Kubernetes. It requires essentially no ongoing management. That said, it can't be ignored that the company went under and now it's in community maintenance mode. If you don't have a specific good use for Rethink's changefeed functionality, which sets it apart from the alternatives, I'm not sure I could recommend it for new development. We've chosen…

Interesting thank you!

I remember back when it came out it was a big deal that it could easily scale master-master nodes and the object format was a big thing because of Mongo back then.

That was before k8's wasn't a thing back then, and most of the failover for other databases wasn't a thing just yet. I'm too scared to use it because they have a community but they're obviously nowhere as active as the Postgres and other communities.

Re: Datomic is Free

#212

Post by augustl »

tyre wrote: post #208
dimitar wrote: post #115

Earlier quoted context omitted.

Consider this use case - in addition to your web app, you have a reporting service that makes heavy duty reports; if you run one at a bad time, bad things might happen like users not being able to log in or do any other important work, because the database is busy with the reports. So in a traditional DB you might have a DBA set up a reporting database so the operational one is not affected. Using Datomic the reporti…

With AWS you can create a replica with a few clicks. Latency is measured in milliseconds for the three-nines observed usage. I don’t think this is a huge challenge (anymore) for Postgres or whatever traditional database.

A few milliseconds per query adds up if you're doing one query per item in a list with 100s or 1000s of elements :)

Re: Datomic is Free

#213

Post by blatant303 »

Datomic is an event-sourced db, and it makes it hard to introduce retroactive corrections to the data when your program's semantic already rely on using datomic's time travelling abilities: at one point you'll need to to distinguish between event time and recording time as explained in this excellent blog post:

https://vvvvalvalval.github.io/posts/2018-11-12-datomic-even...

This is why I' rather use XTDB [1], a database similar to datomic in spirit, but with bitemporality baked in.

[1] https://www.xtdb.com

Re: Datomic is Free

#214

Post by daveguy »

jchw wrote: post #30

Not complaining about the actual announcement itself here: seems pretty sweet all things considered, But: the "Is it Open Source?" section should lead with "No." It's not a complicated question, and it's not a complicated answer. I think it's weird to talk about having "all the same rights" without explaining why that matters particularly (it does matter, it's just not explained much!) but it is somewhat tangential t…

Given the recent bait and switch moves by many companies from free-for-everyone open source to free-for-users-only (eg apache to agpl), it seems like doing this with "binaries only" practically admits to a bait and switch plan.

Re: Datomic is Free

#215

Post by greg7mdp »

gleenn wrote: post #193
PreachSoup wrote: post #187

Earlier quoted context omitted.

Question: What's the difference between nested oop objects (composition over inheiritance) vs maps of nested structures?

Rich Hickey has a great talk about how Objects are data structures with unique interfaces that are unnecessary complexity. He showed and example of a web server with a web request object with request headers etc etc. Doing simple things like collecting information out of that nested object structure is bespoke and harder than it should be for no real gain. If everything is a map or list or set, it becomes completely…

This? https://www.youtube.com/watch?v=aSEQfqNYNAc

Re: Datomic is Free

#216

Post by blatant303 »

PreachSoup wrote: post #187
gleenn wrote: post #174

Earlier quoted context omitted.

Clojure in general is all about passing around little maps of data and in particular not using OO to model. So Datomic naturally continues that by returning maps of nested structures to represent your query results and does side-step the ORM completely.

Question: What's the difference between nested oop objects (composition over inheiritance) vs maps of nested structures?

"It is better to have 100 functions operate on one data structure than to have 10 functions operate on 10 data structures."

Alan Perlis.

Re: Datomic is Free

#217

Post by blatant303 »

hombre_fatal wrote: post #156
stonemetal12 wrote: post #99

Earlier quoted context omitted.

>used Clojure fulltime for five years. How did that work out for you? Usually following a hype cycle, there is a negative hype cycle i.e. Mongo is webscale, then Mongo is a buggy mess. Clojure seemed to just fade away. Did it turn out well or are there interesting pitfalls that make it not as great as advertised?

Clojure is just really niche. Even an ecosystem that stays the same size overtime is dwarfed by the continually growing, continually polished competitor ecosystems that will pull people from the small niches. The best things about Clojure are things you don't really appreciate until you've already done the work to learn them. For example, I never would have known how amazing it was to evaluate code inside the editor…

You don't need paredit. I use Sublime and ctrl+shift+space. Been writing Clojure for 10 years or so.

Re: Datomic is Free

#218

Post by janosos »

bavell wrote: post #202
gleenn wrote: post #193

Earlier quoted context omitted.

Rich Hickey has a great talk about how Objects are data structures with unique interfaces that are unnecessary complexity. He showed and example of a web server with a web request object with request headers etc etc. Doing simple things like collecting information out of that nested object structure is bespoke and harder than it should be for no real gain. If everything is a map or list or set, it becomes completely…

> Unfortunately I can't remember exactly where the part of this talk is. If you or anyone else remembers, I'd love to watch

https://youtu.be/aSEQfqNYNAc

The full video: [Time 0:49:06] https://www.youtube.com/watch?v=VSdnJDO-xdg

Transcript here: https://github.com/matthiasn/talk-transcripts/blob/master/Hi...

Re: Datomic is Free

#219

Post by kaba0 »

gleenn wrote: post #193
PreachSoup wrote: post #187

Earlier quoted context omitted.

Question: What's the difference between nested oop objects (composition over inheiritance) vs maps of nested structures?

Rich Hickey has a great talk about how Objects are data structures with unique interfaces that are unnecessary complexity. He showed and example of a web server with a web request object with request headers etc etc. Doing simple things like collecting information out of that nested object structure is bespoke and harder than it should be for no real gain. If everything is a map or list or set, it becomes completely…

I think there is a need for objects. An active connection, talking to the GPU, etc are not data -- identity is essential for their operation.

OOP is probably the best way to model such,.. well objects, allowing them a private, encapsulated state, and making it only modifiable, or even viewable through a well-defined public interface that enforces all its invariants.

Re: Datomic is Free

#220

Post by LukeEF »

There are already a few open-source alternatives that run datalog variant query languages. I'd point the curious towards TerminusDB [1] and TypeDB [2]. TerminusDB is implemented in prolog (and rust) so an alternative with datalog in the heart.

[1] https://github.com/terminusdb/terminusdb [2] https://github.com/vaticle/typedb

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