Chapter 15. Joining Tables

In this chapter, you’ll learn what joins are, why they are used, and how to create SELECT statements using them.

Understanding Joins

One of SQL’s most powerful features is the capability to join tables on-the-fly within data retrieval queries. Joins are one of the most important operations you can perform using SQL SELECT, and a good understanding of joins and join syntax is an extremely important part of learning SQL.

Before you can effectively use joins, you must understand relational tables and the basics of relational database design. What follows is by no means a complete coverage of the subject, but it should be enough to get you up and running.

Understanding Relational Tables

The best way to understand relational tables ...

Get MySQL® Crash Course now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.