Trying to write a query where I select patients based on a date field. There are 2 dates to be considered, Due Date and Discharge Date. I want to filter only those patients whose Discharge Date was 21 days or earlier than the Due Date. Tried retro-fitting some of the queries in this thread and haven't had much luck. Thanks to anyone who can help!

The Where clause would look something like:

WHERE DateDiff("d", [Discharge Date], [Due Date]) >= 21

That worked perfectly - thank you!