>I see. But the following also works (unless you see something I am missing):
>
>

>IF (!ISNULL(EVALUATE(FIELD(i))) AND ISNULL(OLDVAL(FIELD
>(i), "V_V_MYTABLE"))) OR ;
>(ISNULL(EVALUATE(FIELD(i))) AND !ISNULL(OLDVAL(FIELD
>(i), "V_V_MYTABLE"))) OR ;
>!(EVALUATE(FIELD(i)) == OLDVAL(FIELD(i), "V_V_MYTABLE"))
>

>
>Thank you.

Yes, this seems to be correct.

The version of code I referenced is a little bit longer but more self-explanatory, IMO.