How the system works:

1 - You donate X Amount of dollars.
2 - When it has gone through, the sql table where the players steam id will get that amount added on or created if it does not exist

EXAMPLE:

If jim has 5 in donations on the sql database and donates another 10, it will now be 15.


IN GAME:

Players get their steamid checked against the sql database to see if they have credits.

If they do then load that amount.

They can buy things in game with credits such as ranks.