From: jmjacobs@ix.netcom.com (Jeff Jacobs)
Newsgroups: comp.databases.oracle
Subject: Re: primary keys and indexes
Date: 27 Oct 1994 15:34:50 GMT
Organization: Netcom
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Distribution: world
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In <38ipst$5ht@raffles.technet.sg> shchua@solomon.technet.sg (Chua Song Heng) writes: 

>
>are primary keys in version 7 also indexes?
>i want to know whether i need to create indexes if i am accessing the 
>table through the primary key.
>if primary key already exists, does creating index on the same fields 
>speed up access ?
>
>A prompt reply is appreciated. Thanks.
>
>

The uniqueness of primary keys is enforced by unique indexes.

When you create a primary key constraint, an index is automatically
creates, assuming the constraint is enabled.  (If not enabled, then
the index won't be created).

All of this is covered in the manuals.

-JJ

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