From: Dan Nelson
Date: July 23 2003 9:52pm
Subject: Re: Is it necessary to compress tables?
List-Archive: http://lists.mysql.com/mysql/145949
Message-Id: <20030723215239.GE3178@dan.emsphone.com>
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In the last episode (Jul 23), Jim McAtee said:
> > Does MySQL automatically handle deleted row cleanup, or is it
> > necessary to periodically do this manually for tables with a lot of
> > deletions?  If it's manual, what are the SQL commands to do this?
> >
> > Also, what happens when changes are made to a field definition? 
> > From, say, int to smallint, or tinyint to int, or varchar(255) to
> > varchar(10)?  Do temporary tables get created and the data copied
> > over, or does unused space end up in the data files, to be
> > collected later?
>
> Since I received no responses, maybe someone can take a moment to
> explain why this is such a stupid question.

Maybe not stupid, but definitely "please see the manual" questions.

Answers to Question 1:
http://www.mysql.com/doc/en/DELETE.html
http://www.mysql.com/doc/en/Optimisation.html
http://www.mysql.com/doc/en/OPTIMIZE_TABLE.html

Answer to Question 2:
http://www.mysql.com/doc/en/ALTER_TABLE.html


BTW - Please allow more than 2 hours between question and complaint.


-- 
	Dan Nelson
	dnelson@stripped