in reply to
Writing It Myself, DWIM, and Expectations
Now, I know there's a difference between "" and undef in Perl, just like I know there's a difference between "" and NULL in my database.
Not if your database follows the SQL-92 standard!
Seriously, databases are not supposed to have the idea of an empty string. I learned this from mpeppler when he explained to me why DBD::Sybase was converting empty strings into spaces. Of course to confuse the issue, some databases (eg MySQL IIRC) do allow empty strings.