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Date: Sun, 27 May 2007 20:44:20 +0200
To: "Alexander Staubo" <alex@purefiction.net>
Subject: Re: Feature suggestion : FAST CLUSTER
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> How does it know what to cluster by? Does it gather statistics about
> query patterns on which it can decide an optimal clustering, or does
> it merely follow a clustering previously set up by the user?

	Nothing fancy, InnoDB ALWAYS clusters on the primary key, whatever it is.  
So, if you can hack your stuff into having a primary key that clusters  
nicely, good for you. If not, well...
	So, I used (topic_id, post_id) as the PK, even though it isn't the real  
PK (this should be post_id)...