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Datomic is Free

blog.datomic.com

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Re: Datomic is Free

#321

Post by samuell »

mtnygard wrote: post #225
samuell wrote: post #148

Question to people having used Datomic: Based on experience with Prolog, I always thought using Datalog in a database like Datomic would mean being able to model your data model using stored queries as a very expressive way of creating "classes". And that by modeling your data model using nested such queries, you alleviate the need for an ORM, and all the boilerplate and duplication of defining classes both in SQL an…

You can definitely use Datomic in the way you describe, in at least a few different ways. I haven't often seen queries stored in the database itself. It's more common to have the queries as data in the application. Since queries are ordinary Clojure data structures, it's even more common to see functions that build queries from inputs or functions that transform queries (e.g., adding a tenant-id filter clause). Datom…

Great, many thanks for this elaboration!

Re: Datomic is Free

#322

Post by praptak »

It's free as in beer not as in freedom and the way they formulated that part made me wary of their intentions. (I'm still a huge fan of Clojure)

Re: Datomic is Free

#323

Post by augustl »

bt1a wrote: post #314
augustl wrote: post #212

Earlier quoted context omitted.

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

when do you ever have to do one query per array of items? genuinely curious

I suppose I think of this the other way around. When the query engine is inside your app, the query engine doesn't need to do loop-like things. So you can have a much simpler querying language and mix it with plain code, kind of similar to how you don't need a templating language in React (and in Clojure when you use hiccup to represent HTML)

Additionally, this laziness means your business logic can dynamically choose which data to pull in based on results of queries, and you end up with running fewer queries as you'll never need to pull in extra data in one huge query in case business logic needs it.

Re: Datomic is Free

#324

Post by oblio »

gleenn wrote: post #284
greg7mdp wrote: post #215

Earlier quoted context omitted.

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

Yes, this hit home so hard. All objects are bespoke mini languages that add little to no value and simultaneously make it hard to remember and hard to use. Just use maps!

An object is a schema, though.

A map is... Whatever you put in it.

Re: Datomic is Free

#325

Post by oblio »

xmlblog wrote: post #280
newlisp wrote: post #256

Earlier quoted context omitted.

Welcome to sales tactics ;) Datomic is great but as another commenter said, is good for "small-ish backoffice systems that never has to be web scale". You almost probably can rely on querying history for internal applications. I think their primary market was for companies to use it internally but they never made this clear.

> "small-ish backoffice systems that never has to be web scale". Doesn't production use of Datomic by Nubank and Netflix (to mention just two examples) belie this assertion?

Nubank is one thing, but for Netflix, just like for any big company 10000 DB technologies are probably in use at the same time.

And 9996 of them are used for stuff like the internal HR DB or other minor projects.

Re: Datomic is Free

#326

Post by oblio »

hoffs wrote: post #230
beders wrote: post #170

Every single day I wish the architects at my current job had chosen Datomic instead of Postgresql. It would have saved us so so much time and trouble. The time traveling ability alone would have been so useful so many times. Also the ability to annotate transactions is awesome. So many goodies. Here's a good summary: https://medium.com/@val.vvalval/what-datomic-brings-to-busin...

I am almost certain you don't.

Don't what?

Re: Datomic is Free

#327

Post by KingMob »

xmlblog wrote: post #280
newlisp wrote: post #256

Earlier quoted context omitted.

Welcome to sales tactics ;) Datomic is great but as another commenter said, is good for "small-ish backoffice systems that never has to be web scale". You almost probably can rely on querying history for internal applications. I think their primary market was for companies to use it internally but they never made this clear.

> "small-ish backoffice systems that never has to be web scale". Doesn't production use of Datomic by Nubank and Netflix (to mention just two examples) belie this assertion?

Alternatively, Datomic wasn't performing up to snuff, and they found it cheaper to buy Cognitect than do a DB migration :D

Re: Datomic is Free

#328

Post by KingMob »

nightski wrote: post #67
a2800276 wrote: post #56

Earlier quoted context omitted.

If it wasn't a publicity stunt, it certainly had the effects of one: I've never heard of Datomic before and here they are at the top of hackernews! > And, in practice, it's not that much different for the average user if only the binaries are Apache licensed. When was the last time you needed to open up the Postgres source code and modify something? Sure, if you're playing a game it probably doesn't make a difference…

Rich Hickey started Datatomic (along with Stuart Halloway & Justin Gehtland). He also created the Clojure programming language and has been on Hacker News numerous times with many popular talks. In fact they all have made famous contributions. Many businesses use Microsoft SQL Server or Oracle and don't need access to the source. I'm not saying open source isn't nice, but it is absolutely not a requirement for IT inf…

Gehtland was the CEO of Cognitect, and Relevance before that. I doubt he's written a line of code in years.

Re: Datomic is Free

#329

Post by Moru »

kamma4434 wrote: post #201
brundolf wrote: post #177

Earlier quoted context omitted.

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

Yes, but you end up rewriting Datomic!

Nah, our (not very good) implementation existed 10 years before Datomic :-)

Re: Datomic is Free

#330

Post by KingMob »

moomin wrote: post #100
frou_dh wrote: post #39

Earlier quoted context omitted.

If that's the case then all the people running around praising the ""simplicity"" of golang got the wrong end of the stick completely from Rich's classic presentations.

The thing is, Hickey was entirely right to reject this idea of “Simplicity” being the same thing as “Easy”. But he then decided to conflate in “comprehensible” which it turns out is very much a matter of aesthetics. Turns out if you really focus on composability above other concerns you get Haskell.

The problem is his disdain for "easy". It's one thing to create composable building blocks, but frequently, 99% of users will use them in the exact same way, so you might as well produce the easy thing on top of the simple thing, too.

The Clojure tools.build process has this exact problem. It's too low-level, so everyone got to write their own build scripts on top of that to do the same thing as everyone else. Now there's a situation of a 1000s of bespoke build scripts and 3-4 different front-ends, all effectively doing the same thing.

"In my line of work, sister, sometimes a second chance is a chance to mistake the same mistake twice" - State and Main

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