This is a pragmatic piece of Fowler on the rather dry topic of Object-relational mappings - in short, the attempt to marry an object-oriented code base with a relational data base.
Usually you’d get enough early success to commit deeply to the framework and only after a while did you realize you were in a quagmire - this is where I sympathize greatly with Ted Neward’s famous quote that object-relational mapping is the Vietnam of Computer Science
What Fowler refers to here, is Ted Neward’s article “The Vietnam Of Computer Science”
After working on a few different projects, I’ve always ended up using ORM for normal operations and Stored Procedures for the complex stuff.
If using MS products, the Database project type in Visual Studio even adds some basic static checking to SQL to help you out a little.
Had the pleasure of taking over maintenance of a moderately complex application with a data access layer based entirely on Stored Procedures once - that was fun…