Solution required for a Custom Web Control

Question

Hi

I have almost completed my E-Commerce website and needed help with one of the final implementations.

I need to have an Order Id\Ref upon checking out and thought the best way to go with this would be to...

1. Create an Order Id table in the database.
2. Create a Web Custom Control on the asp page to display the value.
3. Write the code to wire up the plumbing between UI to the DL.
4. Write a list of Order Ids in the database starting from 1 onwards.

I wondered how the auto incrementing of the Order Id can be done. So say that once Order Id 1 has gone how will the page know to display Order Id 2 automatically ready for the next customer?

Thanks

Steven