autocalculating DB fields based on info from other fields

[DANMOP]

When using forms for data entry, I have some fields that need to be
automatically calculated based on the info entered into other fields (ie the
calculated field is a difference in time between 2 other fields with time
entries)

 

[Allen Browne]

See:
Calculated fields
at:
http://allenbrowne.com/casu-14.html

The article explains how to create a calculated field using a query so it
can never be wrong, and under what circumstances you should create
calculated fields in your table.