Gerry Schmitz wrote:"Reference data" is just that; there's nothing to validate. It's like a "comment"; subject to the whims of the client and not something to build a "system" around.
It's not 'Reference data'. It's a Reference Number. The Reference number in the customer's data file is a 'reference' to an Id in the client's accounting system. This matches an invoice from the client to a customer's payment. It's a reconciliation.
But that's not the question. See this[^]
Since my client can define new customers in the app, I need a way for them to tell me the FORMAT of the Reference Number. Then, my app is reading the file, I can verify the number so it can be looked up. The format of the Reference Number CAN be validated. I COULD use a RegEx, but defining the validation for it has to be user friendly.
The question, again, is how to allow the user some way of manually inputting the format of the reference number.
In theory, theory and practice are the same. But in practice, they never are.”
If it's not broken, fix it until it is.
Everything makes sense in someone's mind.