| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
 |
 | |||
| Oracle FAQ | Your Portal to the Oracle Knowledge Grid | |
|
| |||
Home -> Community -> Mailing Lists -> Oracle-L -> Re: RE: Primary keys vs. unique indexes
Hi!
Yes true, but I have not been able to understand WHY the primary key is required to define the foreign key..
Please understand me, I am aware that Oracle has put a restriction of primary/unique key being pre-requisite for foreign key definition, but I am trying to understand the 'reason' behind imposing that restriciton..
Perhaps some design 'guru' can help...
Hannah r u listening!
of course you can.
to quote the 8.1.6 SQL Reference manual restrictions on foreign keys:
The referenced UNIQUE or PRIMARY KEY constraint on the parent table must already be defined.
seems to me that that is pretty clear
>From: "Koivu, Lisa" <lkoivu_at_qode.com>
>Reply-To: ORACLE-L_at_fatcity.com
>To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
>Subject: RE: Primary keys vs. unique indexes
>Date: Thu, 30 Nov 2000 09:20:22 -0800
>
>What? Yes you can. I have anyway.
>
>Can you give me an example of when that would not work?
>
>Lisa Rutland Koivu
>Oracle Database Administrator
>Qode.com
>4850 North State Road 7
>Suite G104
>Fort Lauderdale, FL 33319
>
>V: 954.484.3191, x174
>F: 954.484.2933
>C: 954.658.5849
>http://www.qode.com
>
>"The information contained herein does not express the opinion or position
>of Qode.com and cannot be attributed to or made binding upon Qode.com."
>
>
>-----Original Message-----
>Sent: Thursday, November 30, 2000 11:51 AM
>To: Multiple recipients of list ORACLE-L
>
>
>The main difference is you can not reference an unique
>index with a foreign key.
>--- cemail_at_sprintmail.com wrote:
> >
> > What is the difference between building a table and
> > including
> > the primary key versus building the table and then
> > having creating
> > a unique index on the same keys? When you create a
> > table with
> > a primary key, doesn't Oracle store it as an index
> > anyway?
> >
> > -----
> > Sent using MailStart.com (
> > http://MailStart.Com/welcome.html )
> > The FREE way to access your mailbox via any web
> > browser, anywhere!
> >
> > --
> > Please see the official ORACLE-L FAQ:
> > http://www.orafaq.com
> > --
> > Author:
> > INET: cemail_at_sprintmail.com
> >
> > Fat City Network Services -- (858) 538-5051 FAX:
> > (858) 538-5051
> > San Diego, California -- Public Internet
> > access / Mailing Lists
> >
>--------------------------------------------------------------------
> > To REMOVE yourself from this mailing list, send an
> > E-Mail message
> > to: ListGuru_at_fatcity.com (note EXACT spelling of
> > 'ListGuru') and in
> > the message BODY, include a line containing: UNSUB
> > ORACLE-L
> > (or the name of mailing list you want to be removed
> > from). You may
> > also send the HELP command for other information
> > (like subscribing).
>
>
>__________________________________________________
>Do You Yahoo!?
>Yahoo! Shopping - Thousands of Stores. Millions of Products.
>http://shopping.yahoo.com/
>--
>Please see the official ORACLE-L FAQ: http://www.orafaq.com
>--
>Author: james ellis
> INET: jellis24_gso_at_yahoo.com
>
>Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051
>San Diego, California -- Public Internet access / Mailing Lists
>--------------------------------------------------------------------
>To REMOVE yourself from this mailing list, send an E-Mail message
>to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
>the message BODY, include a line containing: UNSUB ORACLE-L
>(or the name of mailing list you want to be removed from). You may
>also send the HELP command for other information (like subscribing).
-- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Rachel Carmichael INET: carmichr_at_hotmail.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). _____________________________________________________ Chat with your friends as soon as they come online. Get Rediff Bol at http://bol.rediff.com Participate in crazy auctions at http://auctions.rediff.com/auctions/ ------------------------------ From: "Cyril Thankappan" <cyril_thank_at_rediffmail.com> Date: 2 Dec 2000 07:17:18 -0000 Subject: Re: Oracle 8.1.7 on Linux. Hi! can you please tell me at which download site Oracle 8.1.7 for linux is available? Has Oracle solved the rman issue in Oracle 8.1.7? Thanks ------------- Original Message -------------- "Gogala, Mladen" <MGogala_at_oxhp.com> wrote: To:Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com> From:"Gogala, Mladen" <MGogala_at_oxhp.com> Date:Thu, 30 Nov 2000 07:20:24 -0800 Subject:Oracle 8.1.7 on Linux. oracle 8.1.7 EE for Linux suddenly appeared on the download site. does anybody know whether it works on RH7? Are the problems with glibc 2.2 resolved? I am dying to upgrade by wiping my system clean first.... -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Gogala, Mladen INET: MGogala_at_oxhp.com Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing). _____________________________________________________ Chat with your friends as soon as they come online. Get Rediff Bol at http://bol.rediff.com Participate in crazy auctions at http://auctions.rediff.com/auctions/Received on Sat Dec 02 2000 - 01:14:36 CST
 |
 |