msaccess - query with time range

I have a table which contains data readings taken every 90 seconds. I need help defining a query that will allow me to report on instances of data being below a given level for a period greater than an hour, ie if the data reading only drops below a level for ten minutes I'm not bothered but if it drops below a level for longer than 60 minutes I need it to be displayed.



please help........

ta

gg

I have to create a sample data to check it out myself. It is easy to do thru vbprogramming in module. But by query I will try it and reply as soon as possible.



V.Subramanian

subbu@roots.co.in

supersubra@hotmail.com