From: Dan Nelson
Date: June 10 2006 7:30pm
Subject: Re: dropping primary key - 99%CPU
List-Archive: http://lists.mysql.com/mysql/198812
Message-Id: <20060610193005.GB10770@dan.emsphone.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii

In the last episode (Jun 10), Gaspar Bakos said:
> Could someone explain why dropping a primary key of a table (of
> ~1million rec) may take up to minutes of time and 99%CPU?
> 
> Naively, I would have thought that this involves only updating the
> index file.

Currently mysql handles all "ALTER TABLE" commands by rebuilding the
entire table and all indexes.

-- 
	Dan Nelson
	dnelson@stripped