Calculate field in Table.

[Cam]

Hello,

I have a table with a date/time field called CalDate. I
would like to create another field (don't know whether it
has to be a text or date/time field) called NextCalDate
which is one year from the CalDate. Another word is it is
automated/fill in as one year from the CalDate.
Is this possible to do in Access 97?
Thanks

 

[John Vinson]

Hello,

I have a table with a date/time field called CalDate. I
would like to create another field (don't know whether it
has to be a text or date/time field) called NextCalDate
which is one year from the CalDate. Another word is it is
automated/fill in as one year from the CalDate.
Is this possible to do in Access 97?
Thanks

Storing derived data such as this in your table accomplishes
three things: it wastes disk space; it wastes time (almost
any calculation will be MUCH faster than a disk fetch); and
most importantly, it risks data corruption. If one of the
underlying fields is subsequently edited, you will have data
in your table WHICH IS WRONG, and no automatic way to detect
that fact.

Just redo the calculation whenever you need it, either as a
calculated field in a Query or just as you're now doing it -
in the control source of a Form or a Report textbox. The expression
you want is

DateAdd("yyyy", 1, [CalDate])

 

[vbhelpme]

You cannot have a calculated field in a Access table per se. However,
you can use Visual Basic coding to do the calculation for you and have
the value return to your Access table.