select-n-plus-1

Let’s say you have a collection of Car objects (database rows), and each Car has a collection of Wheel objects (also rows). In other words, Car → Wheel is a 1-to-many relationship. Now, let’s say you need to iterate through all the cars, and for each one, print out a list of the wheels. The naive O/R implementation would do the following: And then for each Car: … Read more