Re: regex (not) matching null string

"David M. Kaplan" <dmkaplan@ucdavis.edu> writes:
> I have found that !~ and !~* do not match the null string even when one
> would expect them to.

NULL strings won't match anything.  I can't tell whether your row 3 is
an empty string or a NULL --- but if it's a NULL, this behavior is
not a bug.  Try "s IS NULL" if you want to find NULLs.

            regards, tom lane