I have a table (Excel sheet, whatever...) containing PeopleSoft login information with three columns: Login Time, Logout Time, Time Spent.

My manager has been asked to use that to provide a minute by minute run down of concurrent logins for the entire data set (day).

So, the SELECT for the table is like so:

SELECT LOGIN.Login, LOGIN.[Log out], LOGIN.[Time in]
FROM LOGIN;

Output looks like this:

Login Log out Time in
11/1/10 12:36 AM 11/1/10 12:42 AM 0:06
...

What I need is:

Time Concurrent_Logins
11/1/10 12:36 AM 16
...

So, this is quite complicated. Any thoughts?