Re: postgresql vs mysql

> 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.