Comment by zkomp | Hacker News Reader

Comment by zkomp | Hacker News Reader

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As far as I know, in my experience. Stored procedures in postgres are good when you really use the database and care about the data, you need transactions, need to handle races and concurrency etc. Whereas ORMs break down at this point or prevent you even getting to a point when you can use your database as a database.

Why pretend your SQL database is about objects? It is not... (it is about data)

A stored procedure can act like a view or a query, or use procedural logic. Point is: your app can call it and get a concistent result, no matter what refactoring has been going on.

A direct query needs to know too much about the database (orm generated or otherwise) which prevent refactoring and couples app to database harder...

You can rename or merge tables, views functions in the database but the interface the app use (stored procedures/DAL) will stay the same and work the same way.

As for app logic... I prefer bussiness logic in the database, not the app when the data is important. Application logic stay in your application, data dependent bussiness logic stay with the data.

Every single implementation where I've seen "business logic in the database" has been an unmitigated disaster.

On the other hand, having well factored microservices (out of process) or in process modules have worked out really well with modern devops and software engineering principals - easy push button deployments and rollbacks, unit testing, A/B deployments, etc.

I think bussiness logic in the database has prevented disasters in the projects I have worked on. I honestly dont see how it could have been solved better...

It probably depends on the domain/problems.

My experience is with transaction heavy financial systems or similar, with web frontends, microservices sprinkled around in different languages...

The web app or java worker should be allowed to focus in its problems, the bussiness logic needs to live in one central place, which happens to be in the database accessed through thightly controled interface in the form of stored procedures.

And what's stopping you from having a tightly controlled interface with a REST Api that is easily deployed, rolled back, unit tested, source controlled and deployed?

I like data. A database is created to handle it, give you tools to query, modify, scale, secure the data.

A rest api... how and why should it be responsible for your data? It solved a different problem.

You might not even need a database I guess, and then anything goes.

I need and like my database, and have suffered trying to get along with different ORMs. SQL is so good at what it is designed to do if you just let it.

(And why just one rest api? How about 100 restapis, some microservices, some web apps, some background workers, many different languages. One database. No ORM)

(have we come to some max nesting level here, cant reply to the child comment)

One db can be a problem, or a strenght depending on the domain; And I really dislike religious design, esp microservices.

I have less problems by avoiding ORMs (and religios microservice arch, or fundamentalist interpretations of rest)

Database handles the shared state in a heterogenous environment. We need it to be centralized to keep track of money, the apps can't do that, two independent databases cant do that either. It must be one system that guarantees concistency.

It works great, there is no downtime. The interfaces are defined, the database stands alone, updates are deployed separately.

Database handles the shared state in a heterogenous environment. We need it to be centralized to keep track of money, the apps can't do that, two independent databases cant do that either.

Why can't apps "keep track of money"? I'm assuming you're referring to transactions. Apps can create transactions and you can share transactions across apps using distributed transaction (I'm not saying distributed transaction is a good idea).

One database is still an issue. When you have a clear slice with one microservice being in charge of one set of data, it's easier to scale, slice, rewrite, and you can deploy and iterate faster without interdependencies.

And you lose all of the benefits of microservices if there is still a tight coupling between unrelated (from a domain perspective) to tables.

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