From: Paul DuBois
Date: September 11 2006 6:08pm
Subject: Re: Varchar mystery
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Jerry Schwartz wrote:
> I'm using MySQL Linux version 4.1.21 standard.
>  
> I have a table with fields of a variety of types, including varchar(255) and
> text (which might matter). When I do 
>  
> SELECT MAX(LENGTH(x)) FROM tx;
>  
> where x is a varchar(255), I get back 266 as the result of the query!
>  
> This isn't listed as one of the silent conversions - varchar(256) would be
> converted to text, but not varchar(255). What's going on?

Perhaps you are using multi-byte characters?  LENGTH() returns a length
in bytes. CHAR_LENGTH() returns the length in characters.