Chapter 7

Subqueries versus Joins

The purpose of this chapter is to demonstrate how you can use subqueries as alternatives to joins. There are two main issues to consider in choosing between subqueries and joins (and/or other techniques as well):

image You must consider how you get information, which is often subjective. By understanding the limitations of joins and subqueries (and sets and other techniques, for that matter), you will broaden your choices as to how to get information from a database.

image You must consider performance. You usually have choices ...

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