what is the difference between null and empty function???
Null is a expression. Empty is nothing. It is called isEmpty and is a function
When you work with If or Case there is a chance to check boolean 1 or 0.
If ( YourField = "" ; "Field is empty" )
but it also works with
If ( IsEmpty( YourField ) ; "Field is empty)
other discussions (here) about NULL:
and more if you search for 'NULL'
The SQL NULL is well-known. Other than usage within 'sql' in some form the NULL is not common within FileMaker.
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