• EDIT: Don't get me wrong, the question is great. It applies to MS Access also. NULL is always screwing up my queries. I often wish the DB I work with spent a little more time in the planning stage and NULL was allowed less.

    Although you should limit NULL where possible, I have also found NULL to be a very usefull tool, the problem is knowing of their existance in the first place and taking it into account when you build your query.

    Some people argue that you should put an empty string into a field instead of a NULL. This is not always possible or advisable.

    And if you do some kind of outer join, you will end up with NULLS even if there aren't any in the data tables; so rather than shun them, I say the opposite, embrace the NULL, learn to bend them to your will and you will find that they arent as bad as some people claim.

    At least, that's been my experience.

    -d