lock and transaction

[gianpaolo fabiani]

I have a db with this table

CREATE TABLE `customers` (
`idcustomer` int(10) unsigned NOT NULL auto_increment,
`Customer Name` varchar(45) NOT NULL default '',
PRIMARY KEY (`idcustomer`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

INSERT INTO `customers` (`idcustomer`, `Customer Name`) VALUES (NULL, 'OLDCustomer');

If I execute this operation

START TRANSACTION;
lock table customers WRITE;
UPDATE `customers` SET `Customer Name`='MODIFYcustomer' WHERE `idcustomer`=1;
unlock table;
ROLLBACK;

SELECT * FROM `customers`;
'idcustomer','Customer Name'
'1','MODIFYcustomer'

The record changes. Is it correct? Or is it a bug?


If I execute the same operation with a different order the record doesen't change

lock table customers WRITE;
START TRANSACTION;
UPDATE `customers` SET `Customer Name`='AAAAAcustomer' WHERE `idcustomer`=1;
ROLLBACK;
unlock table;

SELECT * FROM `customers`;
'idcustomer','Customer Name'
'1','MODIFYcustomer'


Thanks
Gianpaolo