on a related but slightly different example, what would happen if you had a
Primary Key consisting of 2 columns a & b (so the pkey enforces a unique
combination of a & b) and then created an index on one of the columns eg b.
Would the index on b have any effect, or does a primary key on 2 columns
work by creating individual indexes on both columns, meaning that there are
now 2 indexes on b and the second one would have no performance effect?
dan
-----Original Message-----
From: Rolf Hopkins [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, 6 February 2001 06:31
To: Jacob Friis Larsen; [EMAIL PROTECTED]
Subject: Re: INDEX() / UNIQUE()
Why would you want to? UNIQUE() is an INDEX() the only difference being
that UNIQUE can not have the same value a number of times whereas INDEX you
can.
----- Original Message -----
From: "Jacob Friis Larsen" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Tuesday, February 06, 2001 21:38
Subject: INDEX() / UNIQUE()
> Is there any idea in using both a INDEX() and UNIQUE() index on the same
> table field ?
>
>
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