Here's a script I don't quite understand:
PostalCode as PostCode,
Where not Exists(PostCode,PostalCode);
What is the use of Where not Exists(PostCode,PostalCode)?
Thanks for help!
Here you go
after you understand the Exist function and in addition to the information described on the link above, you can replace your script by this:
Where not Exists(PostCode);
Retrieving data ...