Retrieve the ip address with php

Sometimes is usefull to know the ip address of our website users, to do this we can use php.
To retrieve the ip address using php is necessary the specific environment variable.

Count the number of rows in a MySQL query, the COUNT function

Many times it'snecessary to count the result lines of a query. There are two ways to do this, php (mysql_num_rows) and MySQL with the COUNT. In this post I show the MySQL COUNT function.

Close a window in one click

With Javascript it's possible close a window in one click, to do this is necessary a link or a button and only one line of code!