HTML5 and CSS3 All-in-One For Dummies, 3rd Edition

Chapter 4

Putting Data Together with Joins

In This Chapter

Using SQL functions

Creating calculated fields

Working with date values

Building views

Creating inner joins and link tables

Single tables aren't sufficient for most data. If you understand the rules of data normalization (see Chapter 3 of this minibook), you know how to break your data into a series of smaller tables. The question remains, though: How do you recombine all these broken-up tables to make something the user can actually use?

In this chapter, you discover several techniques for combining the data in your tables to create useful results.

I wrote a quick PHP script to help me with most of the figures in this chapter. Each SQL query I intend to look at is stored in a separate SQL file, and I can load up the file and look at it with the PHP code. Feel free to look over the code for showQuery on the companion website. ...