Hi,
Char columns are used with fixed-length type table, whereas varchar are used
with dynamic table. If you have varchar columns in your table, all char
columns will be convert to varchar column (you can't have a fixed-length
table if your table contain varchar, blob or text field).
Here are the property of static table :
All CHAR, NUMERIC, and DECIMAL columns are space-padded to the column width.
Very quick.
Easy to cache.
Easy to reconstruct after a crash, because records are located in fixed
positions.
Doesn't have to be reorganized (with myisamchk) unless a huge number of
records are deleted and you want to return free disk space to the operating
system.
Usually requires more disk space than dynamic tables.
Jocelyn Fournier
Presence-PC
www.presence-pc.com
Dans un e-mail daté du 07/05/2001 23:42:12 Paris, Madrid (heure d'été),
[EMAIL PROTECTED] a écrit :
> Sujet :char -> varchar ?
> Date :07/05/2001 23:42:12 Paris, Madrid (heure d'été)
> From: [EMAIL PROTECTED] (Alec Solway)
> To: [EMAIL PROTECTED]
>
>
>
>
> Hi,
>
> In various create table statements char columns are converted to varchar..
> I was wondering why this was happening. Here's an example:
>
> CREATE TABLE realtors(name VARCHAR(255) not null, address VARCHAR(255) not
> null, city VARCHAR(255) not null, state CHAR(2) not null, country CHAR(2)
> not null, zip CHAR(5) not null, phone VARCHAR(50) not null, cell
> VARCHAR(50) not null, fax VARCHAR(50) not null, nvio VARCHAR(25) not null,
> estlead CHAR(5) not null, servicearea VARCHAR(255) not null);
> Query OK, 0 rows affected (0.11 sec)
>
> Here, zip and estlead have been converted to varchar(5).
>
>
> Thanks.
> Alec
>
>
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> Subject: char -> varchar ?
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