In Oracle, a NOT NULL constraint on a table column of VARCHAR in essence
says: "You need to put at least 1 character for a value". There is no such
thing as a zero-length string in Oracle, it's either NULL or it has some
characters.
To make Postgres perform an equivalent column edit, I am considering
defining table columns like ... mycol VARCHAR(20) NOT NULL CHECK (mycol
!='')
Is there any drawback to this? Is there a better way to do it? Any
thoughts? how about ....
mycol VARCHAR(20) NOT NULL CHECK (length(mycol) > 0)
or even
mycol VARCHAR(20) CHECK (length(mycol) > 0)
tia,
Mike