SQL Server find datediff between different rows, sum

Question

I am trying to build a query that analyzes data in our time tracking system. Every time a user swipes in or out, it makes a row recording the swipe time and On or Off site (entr

Answer 1

First you need to talk with the business side and decide on a set of matching rules.

After that I suggest that you add a status field to the table where you record the status of each row (matched, unmatched, deleted etc). Whenever a row is added you should try to match it to make a pair. A successful match sets the status of both rows to matched, otherwise the new row will be unmatched.