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Comment by CuriousSkeptic | Hacker News Reader

My experience with hibernate, entity framework, nhibernate, and lastly dapper has basically left me thinking Dapper is all you'll ever want. I can't imagine a use case where I'd rather opt for NHibernate or EF at the moment.

(I might add, Dapper in combination with C#6 even gives me enough type saftey to be happy. String interpolation and the nameof operator complements dappers DTO approach nicely)

Since you seem to have similar experiences Im curious. When would you ditch dapper for the others?

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> basically left me thinking Dapper is all you'll ever want

Same here. And I don't know anybody who has worked on large enterprise EF systems that hasn't come to roughly the same conclusion. The type safety EF offers is extremely nice to have, no doubt, but the problem is it makes it so easy to create performance problems that _every_ system ends up with them. Probably half of my billable hours in the last few years has been addressing EF performance problems.

Dapper, with a few extensions, can give you type safety for 80% of your typical queries, and the rest can easily be done in stored procedures or with (my preference) Dapper's SqlBuilder. And using SSDT instead of EF code-first, you can easily and in a version-controlled way manage your schema, views, stored procedures, indices, etc., simplifying performance management and getting static analysis in your sql while still not losing straightforward and configurable migrations.

Type safety (no strings) and just as fast as Dapper (actually faster in some cases):

https://github.com/linq2db/linq2db

Do you use a Dapper extension for populating and persisting entities? (Last I looked at it as I recall this wasn't default functionality.)

Dapper does have very low-level basic functionality to insert or update entities. You need to write the SQL yourself so this gets very painful very quickly for complicated models where you want to persist child objects.

That someone would say "Dapper is all they need" leads me to think they only work on very small projects. You will drown in large projects if you use Dapper everywhere. Better to use a high level ORM like EntityFramework and sprinkle in some Dapper in performance critical code.

The only time EF creates performance problems is when the developer doesn't understand the concepts behind SQL. This isn't an ORM problem, it's a training problem.

As I see it, if your model is trivially mapped, you could probably go with something like ormlite on top of dapper. But if you need to custom map you model anyway you might just as well write SQL to map it as some custom dsl mapping thing for the ORM in question.

And, I don't use dapper for performance, I actually like its transparency and friction free interface to the db. Let's me get things done without workarounds. And most importantly, lets me use ssms with a repl flow, copying sql verbatim between vs and ssms.

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