PHP script for creating order numbers with checksum and prefix
I made these two functions to create order numbers with checksum and prefix.
It uses a predefined prefix "OLR" and a 2 digit checksum at the end of the order number. So if real identifier of an order is 1000 the order number will be OLR0100095
1000 => OLR0100095
prefix: OLR
order_id: 1000
checksum: 95