> Does PostgreSQL suffer from this oddity as well? This distinction
> between an empty string and a NULL? Could you also please give me an
> example of where this would be useful from a business logic
> standpoint? Why should a NULL be different from an empty string,
> what's the big mysterious difference?
Nulls are also useful for data that is imported where there is not always a way
to determine
certain field values for a record.
Now suppose in a query you want to return all record that meet your criteria as
well as any that
might meet your criteria depending if the null value was actually known.
Select * from table
Where ((field1,field2,field3) = ('farmer','baker','shoemaker')) is unknown;
Now you can get all records that may meet your criteria.
Regards,
Richard Broersma Jr.
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