This article speaks to me. So many times I have needed to go back and fix queries that were naively written this way like it was some kind of "optimization". There is no difference in effort between writing a join or doing the ORM-double-round-trip in the vast majority of cases. People are so afraid of doing joins I see people doing subqueries with the id in a subselect because "joins are slow". The worst is usually some kind of pseudo-join and then an aggregate or filtering in the application code. It drives me up the wall when I see it in code review, usually because I get into some argument about "joins are slow" (with no evidence) and then I have to go and rewrite the query and maybe add an index to show that, yes - an aggregate that takes seconds and a ton of memory in the application code can in fact take milliseconds in the database.
The NoSQL people have really done a lot of brain-damage to this industry.
It's so pervasive that I've starting using this kind of question in our technical interviews, doing a double round-trip ends the interview for anyone higher than a junior.
The NoSQL people have really done a lot of brain-damage to this industry.
It's so pervasive that I've starting using this kind of question in our technical interviews, doing a double round-trip ends the interview for anyone higher than a junior.