T-sql Reset Row number on Field Change

Question

Similar to a recent post of mine \"t-sql sequential duration\"”, but not exactly the same, I want to reset the row number based on a change in column x (in my case, column \

Answer 1

I had success with this issue by using Rank():

SELECT RANK() OVER (PARTITION BY who ORDER BY custno, moddate) AS RANK

This returned your desired results. I actually found this post trying to solve the same problem.