Query IFF statement that leaves field unchange if condition returns as "false"

[louise]

Hello,
I want to make an IIF statement in a query that evaluates an existing field and, if it is null/blank, makes it equal to another field, but if it is already filled in (I/e., not null/blank) leaves it as it is.

so,
ShortTitle: IIF(Is Null, [...equals LongTitle], [equals itself])



Later, in a form, I want to edit whatever is in that field.

Can you give me some pointers?

Thanks

[JoeM]

Use the NZ function. See: http://www.techonthenet.com/access/f...dvanced/nz.php

Note that you cannot edit a calculated field in a Form, you can only edit the underlying field.

[Micron]

are you sure you cannot edit the control source on the fly? Not that I can think of a situation where that would be a good idea.

[ssanfu]

I agree with Joe; he is 100% correct.

Think about it. If the field in the query is a calculation, where is it stored? Not in a table. If it is not stored, how will you be able to edit the value later? You can only edit data stored in tables or unbound controls on a form.
Since you have created a (virtual) field ("ShortTitle") in a query, there is no way to edit the value later (unless you edit the existing field that the calculation is based on).

[Micron]

Note that you cannot edit a calculated field in a Form, you can only edit the underlying field.

Ok, I think I misinterpreted the meaning. I now realize the user wanted to edit data that was being calculated in a query field. I was thinking more along the lines of changing a calculation in an unbound control by modifying the expression used in the control source.