Ed said:
I was running a report that had been working since the start of my database.
When I attempt to run this report now I get the error message above.
I have not changed anything in either the report or the query .
you are trying to use a null value in a calculation of some sort. Maybe
now one of the fields in your data source has null in it and you later
use that field in a sum or grouping of some sort?
If so always use nz() to convert nulls to something else.
eg if I'm finding the average of a field called pay and there is any
chance of pay ever being null, instead of writing =average([pay]) write
= average( nz([pay]) ). In this case pay will be converted to zero if
was originally null.
I have situations where the field is an alphabetic character and I am
conditionally formatting the field based on a function that I have
written. I pass the value into the function as a string. In that case I
use nz(TheChar,"nothing") instead of just TheChar. Then if TheChar is
null, the nz will convert it to the string "nothing" and my function can
test for it. Without nz it tries to pass a null into a string and I
would get the same error as you.
Howard
