Date Diff Formula

[gheyman]

In a table I need to calculate the Numbers of days between two Fields (ActualStart, ActualFinish)

These two are fields are in this same table.

I assume its a DateDif

 

[gheyman]

Thanks Joe.

I did add a the unbound for the Date difference and it works. But what happened when I have a Field for Actual finish date which I want a default date until the user enters one. The default would be the Actual start date plus that unbound number (number of planned days)? Where and how do I do that? is it not in an "Actual Finish" field under default?

 

[Joe4]

Are you saying what to do when the Actual Finish Date is not populated?
You can use the NZ function to tell it what to use (as a default) if the field is blank.
For example, the following formula subtracts StartDate from EndDate, but if EndDate is null (empty), it uses the current date as the default.

Nz([StartDate],Date())-[EndDate]

See here for a complete explanation on the Nz function: https://www.techonthenet.com/access/functions/advanced/nz.php

 

[gheyman]

Thanks, but I'm still not getting it.

The field Name is "Actual Start Date". Its a Date field that the user will eventually update. But until he does the field should have a default value. I want the default value be the result of a formula. Is this possible?

 

[Joe4]

I don't think you can use formulas as the default values of date fields in a table (though you can use the current date; see: https://support.office.com/en-us/ar...rols-99508d03-b28b-4057-9652-dac1c4c60d86#bm5). However, you can apply your formula logic when you do your calculations. Just use the Nz function like I showed, and put your formula in the second argument of the Nz function. If you look at that link I sent, that last sentence should make sense.