Introduction

In the previous chapter, you were presented with the ways in which PHP can be used to interact with a filesystem in order to process uploaded files, write in text files, and create files and directories, to name but a few aspects. Also, you were shown how a SQL server can be used with PHP to manipulate structured data, such as user accounts or a contacts list.

Handling errors in an application is very important and keeping an eye on them leads to early bug detection, performance improvements, and the overall robustness of the application. Errors can be triggered to signal a number of malfunctions—missing data, bad syntax, deprecated features, and more, and can bring a halt to the script process, depending on severity. For example, when a database connection is not possible, the application would emit a fatal error, which could be handled by writing in a log file, sending an alert email to maintainers/developers with rich trace information (such as connection...