Re: primary keys and indexes

From: Jeff Jacobs <jmjacobs_at_ix.netcom.com>
Date: 27 Oct 1994 15:34:50 GMT
Message-ID: <38ohaq$nl9_at_ixnews1.ix.netcom.com>


In <38ipst$5ht_at_raffles.technet.sg> shchua_at_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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 Internet: jmjacobs_at_ix.netcom.com Received on Thu Oct 27 1994 - 16:34:50 CET

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