[aaronem]

> Yes it probably is an overkill to understand how a db parses an actual SQL

Yes, I've thought that, too, but it turns out that, beyond a certain relatively low level of complexity, that's a great way to produce SQL queries which take a half hour to complete.

> but helpful to understand how an ORM converts to a SQL query.

Certainly, because there's a degree of complexity beyond which your ORM's going to start getting pathological and you're going to have to fall back on querying the database directly, which see point one.