upper limit of "time" entry

[ReneeB]

Can't find an answer to a seemingly easy question... I'm sure you can help o-wise-ones.

How do I put an upper limit on the amount of time allowed in a date/time field?

For example - during a heart procedure a person is exposed to radiation, it will never be more than a total time of 10 minutes. I want to know how much, but I want data integrity so I don't want them to be able to enter more than 10 minutes.


Thanks,
Renee

 

[spikepl]

The simplest? Validation rule in that textbox property:
<=10

You can also use the field's BeforeUpdate event, and cancel the update if the value is not to your liking.

BTW: do not use a date/time field for this but just a numerical field. Access does not know timespans (i.e. length of time from some point to another point in time) but only specific dates and timepoints.

 

[ReneeB]

Ok, that does make sense, thanks.
So if I want min:sec - I have to have 2 data fields and concatenate them when I display/print...?

 

[spikepl]

Hmm.. I may have jumped the gun, in that I doubt that anybody gets more than 24 hours of X-ray exposure

So for small amounts of time, date/time is OK I guess.. you can abuse it like that (just beware how access stores and perceives times and dates http://support2.microsoft.com/kb/210276)

so ,eg., the validation rule for less than 10 minutes would be

<#0:10:00#

 

[ReneeB]

Thanks Spikepl.
I tried that and when I entered it the rule converted to <#12:10:00 AM#
then I gave it a try - I got an error message when I tried 9:00 (9 minutes)
so I entered 00:09, which would be 12:09 AM but it displays 9AM instead of 9 minutes. Then I looked at the format and changed it from short time to nn:ss, same thing.
I think I liked your first idea - number fields, I don't have so many of these that I can't do a minute & second field. Unless you have a different solution.
rb

 

[ReneeB]

Success!!! Thanks so much for your guidance, it really helped. It was a piece of cake when I made them numbers and did a little logical addition
Thanks again