Re: Redefining an existing Table Schema for Foreign Key Constraint - Question
От | Michelle Konzack |
---|---|
Тема | Re: Redefining an existing Table Schema for Foreign Key Constraint - Question |
Дата | |
Msg-id | 20081106213736.GB25016@tamay-dogan.net обсуждение исходный текст |
Ответ на | Re: Redefining an existing Table Schema for Foreign Key Constraint - Question (Harald Fuchs <hari.fuchs@gmail.com>) |
Список | pgsql-general |
Hallo Harald, Am 2008-11-03 13:41:52, schrieb Harald Fuchs: > In article <20294223.post@talk.nabble.com>, > Brian714 <bndang@uci.edu> writes: > > Customers Table > > id:integer -- primary key > > first_name:varchar(50) > > last_name:varchar(50) > > cc_id:integer references Creditcards.id > > address:varchar(200) > > email:varchar(50) > > password:varchar(20) > This is the usual 1:n relationship, but I think you got it backwards. > There are two questions to ask: > 1. Are there customers with more than one credit card? This could be a problem for the above table... > 2. Are there credit cards owned by more than one customer? CreditCards are personaly and sometimes (in France) I need an ID card to prove, that I am the holder... So how can one credit card can have more then one owner? Thanks, Greetings and nice Day/Evening Michelle Konzack Systemadministrator 24V Electronic Engineer Tamay Dogan Network Debian GNU/Linux Consultant -- Linux-User #280138 with the Linux Counter, http://counter.li.org/ ##################### Debian GNU/Linux Consultant ##################### Michelle Konzack Apt. 917 ICQ #328449886 +49/177/9351947 50, rue de Soultz MSN LinuxMichi +33/6/61925193 67100 Strasbourg/France IRC #Debian (irc.icq.com)
Вложения
В списке pgsql-general по дате отправления: