Pros and Cons

The promise of database abstraction is the ability to access any database using identical methods. This gives developers the flexibility to change the back-end database with minimal impact on code. Another advantage of an API such as PDO is a reduced learning curve. Instead of having to learn the specifics of each different database, you can learn one interface and use it with any database. Lastly, with an API you may be able to use features not available to the native database—prepared statements, for example—but more about that later.

On the negative side, a data-access abstraction layer may adversely affect performance and may deprive you of the ability to use non-standard features natively supported by specific databases. It may also introduce an unwanted degree of complexity into your code.

The best way to make a decision about the suitability of PDO is to try it. Converting the SQLite application created in Chapter 15 is a good way to do this. Our SQLite application makes use of a limited number of the features of PDO, so we'll also look at some of PDO's additional capabilities. We won't look at every detail, but this chapter will show you enough to allow you to make an informed decision.

Note:

If you are running PHP 5.0.x you can install PDO using PEAR. See the PHP site for instructions. If you install the latest version of PDO you will be able to use SQLite version 3.