multiple field range

[Guest]

I am trying to find the minimum and maximum values across four fields. Data
is collected four times a day ergo four fields. I need to get the
maximum/min pH for the month. So far all I have been able to find is the
min/max of the individual field. I am very new at access so the help will be
appreciated.

 

[AlCamp]

Nevpoe,
You need to redesign your table.
Try a table with just 2 fields to start with
example tblPHReadings...
PHReadingDateTime - Date Field
PHReading - Numeric

Now using a continuous form (or just the table itself), you would just
make entries as they occur...
Here's 5 sample records...
1/1/05 09:00 12.7
1/1/05 12:45 13.2
1/1/05 17:22 12.4
1/1/05 21:27 14.2
1/2/05 09:15 11.9 etc etc......
Now you can use a Date Range as the criteria for a DMax and DMin lookup
against your data.
hth
Al Camp

 

[Ed Warren]

Al has hit it on the head
Using his design you also do not have to redesign you application when the
'powers that be' decide to start testing 20 times a day and/or drop to 3
times a day.

Cheers,

Ed Warren

 

[Guest]

How do I get the time to be automatically 0200, 0600, 1400, or 1800hrs so
that the that people using to the database cannot enter the wrong times?
These should be there only options for each day.

 

[AlCamp]

nevpoe,
Try setting up 4 buttons on your entry form. Call them
cmd0200, cmd0600, cmd1400, and cmd1800
Users would just click the appropriate button, and the code behind them
would be like...

PHReadingDateTime = Date + #2:00:00 AM# (cmd0200)

Also, if you have the PHReadingDateTime field Format set to
m/d/yy @ hh:nn, your entries will look like...
01/25/05 @ 0200
hth
Al Camp

 

[Guest]

Thanks, I already have the buttons. I will try the date codes.