How to Auto-Increment by Letter, Instead of Number, When Inserting into SQL Table?

Kurt Wireman

Hello, I'm looking for a way to auto-increment by letter (A-Z), for one of my columns in a SQL table. The situation is these are Quality Control disposition codes, so as a new reason is added to the table, I'd like it to increment automatically. Has anyone else had this requirement? Thank you in advance, I appreciate anyone's assistance.

unknown

What happens after the record count exceeds 26 records? Do you move on to AA, AB, AC, AD after Z?
What happens after a disposition code is deleted? For instance, if you have codes A,B, and C and B is deleted; is the next new code inserted B or D?

If you're not expecting to wrap the alphabet, and assuming you have an integer ID field, you can set the letter increment as a derived field: 
SELECT CHAR([interger ID field] + 64) You can test this directly in SSMS by querying SELECT CHAR(1 + 64) This will return the letter A

If your use case will have complicated business logic behind it, I'd consider writing a script to handle the logic and bind the script to a on data change event and keep the business logic in the application layer rather than the database.