I have a bit of a situation with a mySQL DB...
We have a registration queue, which ties a registration ID (Order) to a user in the form of an auto-incrementing key. When the registration process is completed, these users get migrated to another table and removed from the registration queue.
The second table houses the registered users. The registration ID (Order) is then passed into the column labelled 'Invoice'.
Today, the order/invoice numbers have seemed to 'reset' themselves... The previous day, the last Order/Invoice recorded was: 22904
Does anyone know what would cause this? I've been using Primary Keys for years with auto-increment and never have I seen anything like this. The Key type is set at bigint(20) for anyone that is wondering.
Registered users do get removed after the expiry date, but I thought auto-incrementing keys never use previous numbers.
Any help or insight on the matter is greatly appreciated.
Cheers, Matt