How to avoid a null field as a key

[QuickQuestion]

Reading a linked table that uses a postal code to assign the package to the right driver from another table, VB aborts when the postal code is empty (OK when there is a space in the field).

How could I test the rsIn.Field("POSTAL&quot to identify the problem and replace it with a field containing a space?

I tried
if rsIn.Field("POSTAL&quot = " ",
if rsIn.Field("POSTAL&quot = "", and
if rsIn.Field("POSTAL&quot is Null without success.

Thanks for your help

 

[woyler]

try
if isNull(rsIn.Field("POSTAL&quot) then
rsIn.Field("POSTAL&quot = " "
end if

 

[QuickQuestion]

It works. Thanks