I think that's often the case, but from what I hear, EF does a pretty good job.

But keep in mind, ORM is not designed for not should it replace all data access. It designed to handle 80-90% of standard CRUD operations.

>According to an article by Julie Lerman in MSDN Magazine last year, the ORM tools can generate some horribly inefficient SQL. I don't know whether that's true or how frequently it happens but that's what she wrote.