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Datomic is Free

blog.datomic.com

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Re: Datomic is Free

#231

Post by JBiserkov »

brundolf wrote: post #177
augustl wrote: post #173

Earlier quoted context omitted.

Datomic already sort of does this :) You configure a storage backend (Datomic does not write to disk directly) which can be dynamodb, riak, or any JDBC database including postgres. You won't get readable data in PG though, as Datomic stores opaque compressed chunks in a key/value structure. The chunks are adressable via the small handful of built-in indexes that Datomic provides for querying, and the indexes are cove…

Interesting! I assumed Datomic was entirely custom Now I'm even more curious if you could skip Datomic and just do something like this directly with a relational DB in production

But why?! The whole point of Datomic is that it implements this entire immutable framework for you, on top of mutable storage.

So YOU can focus on building your own specific business logic, instead of re-implementing the immutable DB wheel.

Re: Datomic is Free

#232

Post by augustl »

thatwasunusual wrote: post #190

> Datomic's is perfect for probably 90% of small-ish backoffice systems that never has to be web scale (i.e. most of what I do at work). I will also argue that 90% of those don't need this. Just by seeing the term "web scale" makes me shy off.

Anecdotally, all the ones I've worked it where I've used SQL have needed it. I've always ended up wondering when, why and who changed an attribute to its current value, but that's not knowable unless you jump through hoops and manually implement it.

Re: Datomic is Free

#233

Post by JulianWasTaken »

bvanderveen wrote: post #224

From experience: Datomic Cloud is slow, expensive, resource intensive, designed in the baroque style of massively over-complicated CloudFormation astronautics. Hard to diagnose performance issues. Impossible to backup. Ran into one scenario where apparently we weren't quick enough to migrate to the latest version, AWS had dropped support for $runtime in Lambda, and it became impossible to upgrade the CloudFormation t…

I don't doubt your story of course, and I love Postgres, but comparing apples to oranges no?

Datomic's killer feature is time travel.

Did you simply not use that feature once you moved off Datomic (and if so why'd you pick Datomic in the first place)? Or are you using Postgres using some extension to add in?

Re: Datomic is Free

#234

Post by JimmyRuska »

RDFox is worth a try as an alternative, also datalog but C++ based, has incremental reasoning, and explainability. It's a database but also a rules engine that can chain any number of rules. As far as I know datomic is unique for its "query the database at any point in history" and incremental tracking of schema changes, easy to use UDFs, it really shines above other databases in that context.

Re: Datomic is Free

#235

Post by hoffs »

Scarbutt wrote: post #116
dagw wrote: post #98

Earlier quoted context omitted.

Worth keeping in mind that Nubank owns the company that makes Datomic, so that might colour their opinion. On the flip side they probably wouldn't have bought the company if they thought their product was crap.

My guess is they bought the company because they were already too invested in Datomic. So it was kind of forced to minimize risk.

Also helps them to tune it for their use cases where other users have to rely on closed sourceness of it

Re: Datomic is Free

#236

Post by bvanderveen »

JulianWasTaken wrote: post #233
bvanderveen wrote: post #224

From experience: Datomic Cloud is slow, expensive, resource intensive, designed in the baroque style of massively over-complicated CloudFormation astronautics. Hard to diagnose performance issues. Impossible to backup. Ran into one scenario where apparently we weren't quick enough to migrate to the latest version, AWS had dropped support for $runtime in Lambda, and it became impossible to upgrade the CloudFormation t…

I don't doubt your story of course, and I love Postgres, but comparing apples to oranges no? Datomic's killer feature is time travel. Did you simply not use that feature once you moved off Datomic (and if so why'd you pick Datomic in the first place)? Or are you using Postgres using some extension to add in?

We implemented it in Postgres with 'created_at' and 'deleted_at' columns on everything and filtering to make sure that the object 'exists' at the time the query is concerned with. Changes in relationships between objects are modeled as join tables with a boolean indicating whether the relationship is made or broken and at what time.

Our data model is not large and we had a very complete test suite already, so it was easy to produce another implementation backed by postgres, RAM, etc.

Re: Datomic is Free

#237

Post by newswasboring »

thomastjeffery wrote: post #138
newswasboring wrote: post #127

Earlier quoted context omitted.

Is it though? Seems to me that most marketing today is subterfuge.

Is most marketing good? I don't think so.

I don't know what you are calling "good". That is a super loaded word. I would say it is effective though. The baseline evidence for that is how much money gets spent in that industry, I guess.

Re: Datomic is Free

#238

Post by mardifoufs »

Naomarik wrote: post #58
endisneigh wrote: post #4

The price is certainly right, but has anyone used this in production? What was your experience like?

https://sayartii.com/ is using Datomic stored on postgres that I have set up on Linode. That was all done back in 2020 and haven't needed to touch it. Site now gets ~180M monthly reqs and I store an enormous amount of analytic data on Datomic (was supposed to be temporary) so users can see impressions/clicks per day for each advertisement. I'm surprised it's still working. Development experience is extremely nice usi…

Was it expensive to run? Now that it is free, I guess that's less of a concern!

Re: Datomic is Free

#239

Post by thomastjeffery »

newswasboring wrote: post #237
thomastjeffery wrote: post #138

Earlier quoted context omitted.

Is most marketing good? I don't think so.

I don't know what you are calling "good". That is a super loaded word. I would say it is effective though. The baseline evidence for that is how much money gets spent in that industry, I guess.

> The baseline evidence for that is how much money gets spent in that industry, I guess.

I can't imagine a clearer example of circular reasoning.

I can lift exactly as much weight as I decide to put on the barbell.

Re: Datomic is Free

#240

Post by kaba0 »

gleenn wrote: post #226
kaba0 wrote: post #219

Earlier quoted context omitted.

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.

Clojure uses objects for connections and things, but POJOs are harmful IMHO because it makes manipulation and collecting data a bespoke task every time. Every time you change the data, you have to change a class to represent the JSON and the ORM class and .... this is all just data

Well, that’s what Java records are for. As for having to change the type description, that’s more of a static typing discussion, though it can be generated — having a single source of truth and generating others is imo the best approach.
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