This tutorial is a bit the same as the counters tutorial except that it deals with the time aspect as well.

MyISAM does not have any key constraints. This means that you can't cascade deletes and updates to other tables as you would normally do. You can however simulate the Foreign Key Constraints using triggers.

Triggers are a great way to gateher statistics and have 'running progress counters'.

SQL injection is most common methodology employed by a hacker to exploit vulnerabilities in software applications. Vulnerabilities are basically weak links in the software that exposes unauthorized data/information to a user...

MySQL FAQs - Server Daemon mysqld Administration.

Advanced SQL using MySQL and phpMyAdmin.

The reason for having a database is to have vast amounts of data organized and readily available. SQL is the means by which we can communicate with the database and tell it to find exactly what we need...

When running more complex queries, such as concatenating strings, often times you may need to trim whitespace from the values.

Aggregate means a whole, the term is most used in economics (if you have ever taken an economics class, you probably remember how painful it was :)), it basically means ‘as a whole’. So, we’ll cover a few simple aggregate functions , avg,max, and min.

A word of warning about concatenating with sql, if the data used is one that is created by a user where query strings are created dynamically, there could be a possibility of an sql injection. This method is best used for outputting information you have in a database...