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From:Shankar Unni Date:October 24 2001 4:48pm
Subject:Re: Length limit of 500 on primary keys?
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Steve Meyers wrote:

 > In a previous message, I failed to mention one of the main reasons you
 > would NOT want to use a 500-character primary key.  MySQL uses a key
 > buffer to keep as much index information in memory as possible.  The
 > longer the key, the less info it can keep in memory, and the more
 > often it will have to swap to disk.  If your key doesn't fit in the
 > key buffer, my tests have shown that there is a HUGE performance loss.

That's a very good point - thanks for bringing it up.  I'll bring it to the 
attention of the table's owner. Thanks for the ammo..

(Fortunately, this table isn't very big..)
--
Shankar.

Thread
Length limit of 500 on primary keys?Shankar Unni21 Oct
  • RE: Length limit of 500 on primary keys?Chris Bolt21 Oct
    • RE: Length limit of 500 on primary keys?Steve Meyers21 Oct
      • Re: Length limit of 500 on primary keys?Shankar Unni22 Oct
        • RE: Length limit of 500 on primary keys?Steve Meyers22 Oct
          • Re: Length limit of 500 on primary keys?Jeremy Zawodny23 Oct
            • RE: Length limit of 500 on primary keys?Steve Meyers23 Oct
              • RE: Length limit of 500 on primary keys?Steve Meyers23 Oct
                • Re: Length limit of 500 on primary keys?Shankar Unni24 Oct
              • Re: Length limit of 500 on primary keys?Bill Adams23 Oct
                • RE: Length limit of 500 on primary keys?Steve Meyers23 Oct
              • RE: Length limit of 500 on primary keys?Don Read23 Oct
            • Re: Length limit of 500 on primary keys?Dan Nelson24 Oct
Re: Length limit of 500 on primary keys?Heikki Tuuri23 Oct