Another quick Data Analysis eXpressions (DAX) update, given that I’ve been playing about with PowerPivot again this week. Following on from my exertions trying to work out how to return a month name in DAX, I found myself looking for a DAX equivalent of SQL Server’s
DATEDIFF function. Fortunately, this is reasonably straightforward. All we need to do is perform a regular subtraction on two dates and multiply the result by 1.0, which will return the number in serial date-time (the number of days since “1900-Jan-0”, which is how Excel stores dates).