Joe Celko's Thinking in Sets: Auxiliary, Temporal, and Virtual Tables in SQL

11.2. Heuristics

The following tricks and heuristics are not exactly mathematically precise scientific methods. In fact, some of them sound pretty weird. But as Larry Constantine once remarked, a method is a list of things that tells you what to do next, when you did not know what to do next. And you hope the method at least gets you to a workable solution, if not a good solution.

11.2.1. Put the Specification into a Clear Statement

This might sound obvious, but the operative word is “clear” statement. You need to ask questions at the start. Let me give some examples from actual problem statement having to do with a schema that models a typical orders and order details database.

1. “I want to see the most expensive item in each order.” How do ...