We have an app that receives, process and sends a string data in a particular format. I will explain this with a sample in that format. We have "**AB-123456**" where "**AB**" is always alphanumeric, "**123456**" is currently numeric, and "-" is the separator. We have a length and format restriction in place at our client side. 

Now, we want to update the format to "**AB-123456-1**" to meet a new business requirement, but the client team doesn't agree with that, since it will break their length restriction checks. But they are fine to use alphanumerals. One of the solution we proposed is to convert that number ("**123456**") to hex (we will get "**1E240**"), so the final representation of `AB-123456-1` will become `AB-1E2401`. I would like to check whether there is an alternate solution available for this type of problem.

The hex representation stays invisible to the customers. It is an indirect customer transaction and is not rendered in UI (it is a web service call). Our client use this field (specifically the numeric field) in their databases as unique field. As our client saves it as string in the database, converting to hex is ok for them, but it is more work for them if we are increasing the field length. In our end, we just receives the data, process it and send to the client.