> Someone that uses an ORM knows when they shouldn't use them

That's not been my experience. But admittedly, I've usually been brought in when the slow query is killing the database. Then I look at the query that nobody with any subject matter knowledge would have written, come up with an alternate query that will give either the same result or something close enough. Sometimes I have to then dig in and figure out how to make that happen, because the ORM user doesn't always know how to make direct queries.

But it sure did make the easy things easier, as the other poster said.

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hparadiz an hour ago | parent [-]

People focus on the query writing aspect of ORMs too much. That's not that primary reason you use an ORM. It's primary purpose is to hydrate objects in the runtime. If I pull a datetime from SQL there's a lot of value in having a single piece of code handle that datetime the same way across the entire stack. I can unit test that handling once across the entire code base. Very few ORMs are aware of how the data is indexed and yes a lot of people will write code that generates a complex WHERE clause against columns that aren't indexed. But that's an understanding problem. I expect someone who uses an ORM to understand SQL well. Including indexes and fixed length tables. Obviously you are encountering code made by people who don't understand this but the problem isn't the ORM. They would have made that mistake with or without an ORM.

	▲	toast0 44 minutes ago \| parent [-]
		> I expect someone who uses an ORM to understand SQL well. From experience, I don't. ORMs are usually sold as 'learn this instead of learning SQL'. For many, the ORM creates the tables, alters the tables, and queries the tables; they don't see SQL and they don't know SQL. When that works, it works, but when it falls apart, they have to debug the SQL and the abstraction layer. I'd rather have fewer unnecessary abstraction layers. > If I pull a datetime from SQL there's a lot of value in having a single piece of code handle that datetime the same way across the entire stack. There's value there, datetimes are very complex, but the rest of the stuff it comes with obscures the value IMHO. > Obviously you are encountering code made by people who don't understand this but the problem isn't the ORM. They would have made that mistake with or without an ORM. It's hard to write the kind of complex queries I've seen by hand, and I like to imagine if you out how to do that, you'll also know why it's slow and not need my help... But the ORM is part of the problem, because when you've written bad queries by hand, and I give you a better query (or sequence of queries), it's easy to apply. When you've done it with an ORM, you may not even know where the query is made.