Query on previous row value

Here's my problem. I need to generate a query that will display a date field then the computed time lapse from the queries' previous row.

T_DATE

11:34:17
11:35:32
11:42:32

I need to display

T_DATE TIME_LAPSE
------- --------

11:34:17   (null)
11:35:32   00:01:15
11:42:32   00:07:00

Please advise. Thanks

Jeff Received on Fri Apr 12 2002 - 14:44:25 CDT