Default value

[Guest]

Whenever I use the expression builder to select a field name in building an
expression in the default value property of a table field I get an error on
saving the table. How do I correct this?

 

[Allen Browne]

Access applies the Default Value before you begin entering any fields in the
new record. Since the field's don't have a value at this time, you cannot
make the Default Value of one field dependent on the value in another field.

One alternative is to use the AfterUpdate event of one control (in a form),
to set the value of another if it still IsNull().