Re: Difference of Primary key & Unique Indexes...

In a nutshell (and probably open to correction)

A Primary key uniquely identifies the record within the entity/table , where as a unique index uniquely identifies the column within the record. I have a table with invoices , a Primary key on the invoice_id column uniquely identifies each record, and prohibits duplicate invoices, whereas a unique index on part_number and part_line_number uniquely identifies each line on the invoice...Not the best example but I hope it helps.

Regards

Adrian
cucu_at_nongae.gsnu.ac.kr wrote in message
<34ad8ad1.347432982_at_news.snu.ac.kr>...
>Hi everybody...
>
>I'd like to know the difference of Primary Key and Unique Index.
>(PK : Primary Key, UI : Unique Index )
>Is there any difference of performance PK and UI?
>or
>what's the particular difference of PK and UI?
>
>Thanks in advance and mail me.
>
>ksjune_at_sys.gsnu.ac.kr
>
Received on Sat Jan 03 1998 - 00:00:00 CST