Re: NULL vs NOT NULL in database

Your scenario is common. Like a wholesale company sells to individual mom-and-pop stores and big, multi-division/location chains. I'd put the branch/dept/division information in its own table. --- manel@semic.es (Manel Falc' i Aige) > wrote: >Imagin you have two kinds of customers that you want to invoice. The >first one doesn't have any branch or department (or maybe sometimes) >and the second one always has some branches or department. > >Therefore, the bills file could have costumer+branch as composite >primary key. Branch key could be sometimes null (o space) because not >always is required, but it's a key since you could have some files >related to, for exemple discounts, payment files for each customer or >customer+branches. Here is the join problem. Branch must be blank. > >So, As input statements don't accept blank value ... You'll have to >put it afterwards... and it's a nuisance ... > >Well, despite of my English I hope you have understood it ... > >Regards from Lleida, a little corner from Catalonia, Spain. >Manel Falc' > == Maintainer of the procrastinator's FAQ. Well, maybe tomorrow I will be. _____________________________________________________________ Want a new web-based email account ? ---> http://www.firstlinux.net