I would agree with the comments made on P19, that it seems impossible to find advice about strategies for avoiding the 'n+1 selects' problem.
It is difficult finding references to articles describing the issue by other sources. The explanation and example given in section 13.2.5 (pages 584-588) is great, I would just like to do more background reading to help me better understand all of the issues involved.
The only one I found so far is :
Please let me know if you have come across any other links about this issue, maybe described under a different name.