Not necessarily. Sometimes the child will just have its own key
(InvoiceDetailId) and a foreign key to the Invoice table, InvoiceNumber.
Keri Hardwick
TC wrote in message <01beb294$fa0e55e0$53fa98cb_at_pentium>...
>
>Brad Pybus <brad_pybus_nospam_at_hotmail.com> wrote in article
><%%v73.1733$sk1.2500_at_client.news.psi.net>...
>> We never use multi-field primary keys.
>
>
>But how can you avoid so doing?
>
>In any master/detail relationship, the detail record will normally need a
>composite primary key, namely:
>* the master key of the parent table, plus
>* the extra field which distinguishes the child records for a given master.
>
>For example:
>* Invoice Header -primary key = InvoiceNumber;
>* Invoice Detail - primary key = (InvoiceNumber, InvoiceLineNumber).
>
>Yes? No?
>
>TC
>(No email)
Received on Wed Jun 09 1999 - 11:43:31 CDT
