My problem is this:
I have a table 'history' with columns for ''date_time', 'event', 'sensor'.
The 'event' column may contain 'Calibrated', 'Damaged', 'Repaired'.
Since it is a history, the same sensor may be listed multiple times with a
date for each event.
I want only the most recent calibration event for undamaged sensors.
I am trying to figure out how to winnow out in a single query (no
intermediate
tables) the most recent event for each sensor which has been 'Calibrated' or
'Repaired' not 'Damaged' afterwards.
I had thought it would be so simple. But after much wrangling I seem to be
stumped.
--
Mistera Sturno - Rarest Extinct Bird
<(+)__ Gan Uesli Starling
((__/)=- Kalamazoo, MI, USA
`||`
++ http://starling.us