Explain this syntax?

[#1]

Hi,

ISNULL(Fieldname) <> -1   means what?

[luciancotea · Accepted solution]

ISNULL(Fieldname) <> -1

ISNULL(Fieldname) <> TRUE()

ISNULL(Fieldname) = FALSE()

NOT ISNULL(Fieldname)

Means if Fieldname is not null

[Peter_Cammaert]

-1 corresponds to the value true.

The expression equals:

IsNull(FiueldName) <> true()

[#4]

Take text-box & put =ISNULL(Fieldname)

If result is -1 then it states field contains Null values else if returned result is 0 then not null..