When to Stop Optimizing

The previous sections discussed simple queries. Even there we found ways to improve the queries, sometimes with increasingly better results over several iterations of tuning. When you work with complicated queries with a lot of JOIN conditions, a lot of columns in WHERE clauses, and GROUP BY clauses, you have even more choices. It’s possible to imagine that you could always find a way to make performance even faster and that these improvements can continue forever. So the question is when to consider a query properly optimized and put a stop to the research.

An in-depth knowledge of performance techniques could help you choose the proper solution. But there are still basic considerations that can help you to stop, even if you don’t consider yourself an expert.