mysql> show create table UserReports\G
*************************** 1. row
> ***************************
Table: UserReports
Create Table: CREATE TABLE
> `UserReports` (
`rolID` int(10) unsigned NOT NULL,
`repID` int(10) unsigned NOT NULL,
> PRIMARY KEY (`rolID`,`repID`),
KEY `repID` (`repID`),
CONSTRAINT
> `UserReports_ibfk_1` FOREIGN KEY (`rolID`) REFERENCES `UserRoles` (`rolID`) ON DELETE
> CASCADE,
CONSTRAINT `UserReports_ibfk_2` FOREIGN KEY (`repID`) REFERENCES `Reports`
> (`repID`) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=latin1
1 row in set (0.00
> sec)
----- Original Message ----
From: Baron Schwartz <baron@stripped>
To: Josh
> <josh2780@stripped>
Cc: mysql@stripped
Sent: Saturday, October 27, 2007
> 10:17:32 AM
Subject: Re: Table Size
Josh wrote:
> Hello,
>
> I have a database that is growing at a rate of 4-5 MB per day (that number is getting
> larger as well). Not too bad but I'm trying to clean up the tables to minimize the amount
> of space they take up.
>
> I have one particular table that has 2 columns:
> rolID int(10) unsigned
> repID int(10) unsigned
>
> Both are foreign keys to other tables.
>
> A "show table status" shows that this table has a Data_length=1081344 bytes.
> http://dev.mysql.com/doc/refman/5.0/en/storage-requirements.html shows that integers take
> up 4 bytes of space.
> There are currently 10472 rows in the table.
>
> 10472 x 4 x 2 = 83776
>
> What am I calculating wrong? Why is the Data_length value so much larger?
It depends on
> the storage engine, indexes, and possibly other things.
What's the output of SHOW CREATE
> TABLE for this table? If you can't
tell us that, what's the storage engine?
(yes, I
> know Index_length is separate, but humor me).
Baron
