From: Martijn Tonies
Date: March 16 2006 6:58pm
Subject: Re: NULL columns
List-Archive: http://lists.mysql.com/mysql/195897
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> When doing an insert using NULL in the insert request, 
> what really is being written in the column?
> Is the word NULL being written? 
> Is any real space being consumed?

In the cases that you really want to store NULL ;-)


No, it's not the word "null".

Of course space is consumed.

How much depends, see, for example:
http://dev.mysql.com/doc/refman/5.0/en/static-format.html
or
http://dev.mysql.com/doc/refman/5.0/en/dynamic-format.html

This is for MyISAM, InnoDB behaves differently.

Martijn Tonies
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