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From:Paul DuBois Date:May 26 1999 2:15pm
Subject:Re: SHOW COLUMNS confuses CHAR/VARCHAR
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At 8:49 AM -0500 5/26/99, kai@stripped wrote:
>>Description:
>The output of a
>  show columns from TABLE
>command has problems with CHAR and VARCHAR columns. The script in the next
>section produces the following output:
>
>Field	Type	Null	Key	Default	Extra
>Code	varchar(8)	YES		NULL
>Bank	varchar(40)	YES		NULL
>Method	char(2)	YES		NULL
>Name	varchar(40)	YES		NULL
>
>Each VARCHAR column was created as a CHAR column, and the CHAR column was
>created as a VARCHAR column.
>
>>How-To-Repeat:
>Execute the following script:
>
>#!/bin/bash
>set +x
>
>mysql -u root <<EOF
>
>drop database if exists bug;
>create database bug;
>use bug;
>
>create table Tab1 (
>  Code CHAR(8),
>  Bank CHAR(40),
>  Method VARCHAR(2),
>  Name CHAR(40)
>);
>
>show columns from Tab1;
>EOF
>
>>Fix:
>	???


MySQL silently changes CHAR(N) to VARCHAR(N) for N>=4 if you have any VARCHAR
columns since by including such columns in your table, the records become
variable-length anyway.

Reference:
http://www.mysql.com/Manual_chapter/manual_Reference.html#Silent_column_changes

--
Paul DuBois, paul@stripped
Northern League Chronicles: http://www.snake.net/nl/
Thread
SHOW COLUMNS confuses CHAR/VARCHARkai26 May
  • Re: SHOW COLUMNS confuses CHAR/VARCHARPaul DuBois26 May
    • Re: SHOW COLUMNS confuses CHAR/VARCHARA. Brandic26 May
      • Re: SHOW COLUMNS confuses CHAR/VARCHARPaul DuBois26 May
        • Re: SHOW COLUMNS confuses CHAR/VARCHARA. Brandic26 May