In some cases, multiple WordPress installations may become necessary. However, a problem arises when your host does not have enough MySQL Database allowance. You can alleviate this problem by installing multiple WordPress incarnations in one database.
For this you must install WordPress manually. One click programs like fantastic may prevent you from choosing the proper prefix.
You see, in order to allow multiple installations, you need to change the prefix “wp_“ during the installation in your config.php phase. You can use a different prefix and then use them for multiple WordPress installations. For example, your first one can be wpchris_ and the next can be wpben_ etc.
The prefixed SQL address will secure your blogs from the hackers. It will be very difficult for them to find out your SQL address with an unusual prefix. In fact, adding a prefix can also help you secure your single WordPress install.