Thanks, Jeff, very useful! I ran in to the datetime2 issue just yesterday while trying what turned out to be an unnecessary modification to my audit system. It's kind of odd: I don't recall doing a lot of datediff work over the years until this job where we need awareness of expired eye exams and such.
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[font="Arial"]Knowledge is of two kinds. We know a subject ourselves or we know where we can find information upon it. --Samuel Johnson[/font]