On Sun, Mar 18, 2001 at 03:58:46PM -0500, Ryan Shrout wrote:
>
> Could someone explain to me the difference between the
> Primary/Index/Unique attributes of MySQL? I am coming from using MS
> SQL where there is only the Primary key option.
And INDEXed column may have duplicate values in it. A UNIQUE one may
not.
A PRIMARY KEY is simply another way to say "UNIQUE" with the
side-effect that the PRIMARY KEY is stored first in the index file for
the table.
So UNIQUE is a special case of INDEX, and PRIMARY KEY is a special
case of UNIQUE.
Jeremy
--
Jeremy D. Zawodny, <[EMAIL PROTECTED]>
Technical Yahoo - Yahoo Finance
Desk: (408) 328-7878 Fax: (408) 530-5454
Cell: (408) 439-9951
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