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Comment by teacup50 | Hacker News Reader

> If you're not using an ORM, then you ultimately end up writing one.

Only if you assume that Object Relational Mapping is the only way to express type checked database access at the application layer.

ORMs are broken by design; there's no lossless bridge between relational theory and OO -- only inconsistent, error-prone, complex approximations.

Instead of bringing relational theory to the programming language, ORMs try to emulate OO behavior/method dispatch/etc in a world of transactions, deadlocks requiring retry of previous operations, on-disk serialization of data, etc.

In 2016, it's ORMs that are outdated.

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This. Ye Gods, this.

A project with nontrivial data relationships should start with the data model, not with a code model superimposed on data. ORM leads to bad data models and performance problems that are unfixable.

If only people would listen to this advice. The number of times I have started a project by trying to think about the data model only to get told "just build the models, we can change it later" drives me insane. Code is easy to change, your data model is not once it is in production.

Only if you use a single, concrete data model. If your domain supports the use of something like event sourcing, your "data model" is surprisingly easy to change. Or in this case, is = are, and data model = data models, and they're actually derived from your domain events, which can be replayed. At any time.

testify Brother/Sister Testify

Yep, for years my bias has been trending to the relational method of modeling data rather than the object oriented way.

The relational model is more flexible -- you can slice data up in any number of ways, rather than through a fixed hierarchy.

The relational model was developed by Date/Codd to address the needless complexity and brittle nature applications built around network or hierarchical databases of the 60s/70s, which are in many ways analogous to today's OO relationships.

More like relational databases are outdated. There was one truly committed effort to bring the database model into the programming language - EJB - and there's a reason it's now a curse word. The successful systems of the past ten years have been those that moved away from the relational model, using simple datastores controlled by application code.

I'd bet that there is more code written in the past 10 years that uses SQL, than that which uses "simple datastores". You don't hear it much, because it just works, all the problems are well known (and so are the various solutions & workarounds), and so it's boring. Whereas, "Company X has adopted No-SQL solution Y for its project Z! That means it works!" makes headlines.

Probably true as far as it goes. But I think that SQL is a smaller percentage of systems now than it was 10 years ago, and that the trend continues to be in that direction.

Only if you believe type theory and typed programming languages are outdated.

I'm not impressed with NoSQL; they have no answer to the limitations of relational theory beyond simply abandoning formalism entirely.

I believe type theory and typed programming languages are very valuable. But if you keep your logic in code and your store as a dumb store then the store doesn't need to know about them.

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