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Datomic is Free

blog.datomic.com

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191–200 of 436 posts

Re: Datomic is Free

#191

Post by bruiseralmighty »

electroly wrote: post #53
augustl wrote: post #11

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). Writing in a single thread removes a whole host of problems in understanding (and implementing) how data changes over time. (And a busy MVCC sql db spends 75% of its time doing coordination, not actual writes, so a single thread applying a queue of transactions in sequence can be fast…

> Someone needs to have the working set of your database in memory, why shouldn't it be your app server and business logic? This one confused me. The obvious reason why you don't want the whole working set of your database in the app server's memory is because you have lots of app servers, whereas you only have one database[1]. This suggests that you put the working set of the database in the database , so that you s…

This is true, but the tradeoff is that now your central DB is a bottleneck that is difficult to scale.

Having the applications keep a cached version of the db means that when one of them runs a complex or resource intensive query, it's not affecting everyone else.

Re: Datomic is Free

#192

Post by thewataccount »

electroly wrote: post #183
thewataccount wrote: post #180

Earlier quoted context omitted.

Is RethinkDB still around? They actually have recent commits, and a release last year.

The company is gone, but the open source project lives on. We still use it in production.

How's it been for production?

Would you recommend using it, or would it be better to go with a safer option?

Re: Datomic is Free

#193

Post by gleenn »

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?

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 trivial to extract and manipulate data from a structure. It's a subtle difference at first but when everything is like that it makes your system far simpler. Unfortunately I can't remember exactly where the part of this talk is.

Re: Datomic is Free

#194

Post by tasuki »

riku_iki wrote: post #189
alecco wrote: post #92

Earlier quoted context omitted.

Just the temporal properties alone make it very useful for anything where it matters like billing, finance, inventory. Else you are in views/schema/indexing hell to do it on top of SQL. There is some SQL temporal support but it's not great and varies a lot. Also since it's not native to the storage it has a lot of complexity issues under the rug making it not great. Many financial systems use Event Sourcing (OOP + OR…

> Just the temporal properties alone make it very useful for anything where it matters like billing, finance, inventory. you can easily create datamodel to have this in SQL dbs: create table transaction_history(..., execution_time timestamp);

This is not an answer, it's the beginning of a question. Yes sure, we know `create table` and we know it's a good idea to record the execution timestamp. What exactly do you put in the place of the three dots?

Re: Datomic is Free

#195

Post by electroly »

thewataccount wrote: post #192
electroly wrote: post #183

Earlier quoted context omitted.

The company is gone, but the open source project lives on. We still use it in production.

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 not to rip it out, but we're not developing new things on it.

Re: Datomic is Free

#196

Post by chrisjc »

espeed wrote: post #186
chrisjc wrote: post #157

Earlier quoted context omitted.

Curious why you're asking this question when it seems to have little to do with Datomic going "free"? Did you mean Datomic WASM on the horizon? Or am I missing some other connection between SQLite and Datomic?

Datomic Wasm backed by SQLite.

Interesting!

What are you using SQLite for? If it's analytics, perhaps DuckDB WASM might be an option?

Re: Datomic is Free

#197

Post by slim »

erichocean wrote: post #165
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…

Eh, it's Java bytecode and it's Apache 2. So you can patch Datomic and extend it without breaking the license.

You can also probably decompile it

Re: Datomic is Free

#198

Post by ingenieroariel »

simonw wrote: post #7
NickBusey wrote: post #2

Free as in beer. Not free as in speech. > Is it Open Source? Datomic binaries are provided under the Apache 2 license which grants all the same rights to a work delivered in object form. Datomic will continue to be developed at Nubank, where it is a critical piece of our infrastructure.

I find that answer confusing. I don't think I've ever seen binaries being licensed under Apache 2 without the relevant source code before.

I saw Fabrice Bellard do it this year (MIT): The CPU version is released as binary code under the MIT license. The GPU version is commercial software. Please contact fabrice at bellard dot org for the exact terms.

https://bellard.org/ts_server/

Re: Datomic is Free

#199

Post by TheCoelacanth »

nerdponx wrote: post #86
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…

I didn't realize it was possible to release binaries under a different license from the source code that generated them. In this case, is the "source code" just the physical machine code or bytecode in the binary?

If you think about it, that's happening every time that you get a closed-source binary distributed to you. They're giving you a license to the binary, but not to the source.

It's certainly weird for the binary license to be Apache, rather than some proprietary EULA, though.

Re: Datomic is Free

#200

Post by samuell »

gleenn wrote: post #174
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…

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.

Thanks for the comment!

I was more thinking of the means to define your data "classes" (or whatever it is called on this context) though, rather than how it is passed around.

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