mysql_connection class is in charge of establishing a connection to the MySQL server. This class is a wrapper of the basic functions like open, close, send sql, send command. It allows personnalized error trapping and can also trap errors for you but in a very gruesome way stopping all execution.

mysql_connection class also offers several usefull functions like:
- sql_insert_id() which returns the last inserted id by this connection
- sql_data_format() which will transform any ' into a ' format so the sql string will not suffer brutal stops because of a misplaced '

The basic information you need to use this class is what follows:
Step 1: Create the object
needed: hostname, username, password and database used by this connection
Step 2: Open the connection
call: open()
Step 3: Send any sql request or sql command
call: send_result_sql() or send_command_sql()
Step 4: Close the connection