If i've the following database
CREATE TABLE `my_table` (
`year` text,
`event` text
) ENGINE=MyISAM DEFAULT CHARSET=utf8;
INSERT INTO `my_table` VALUES ('2011', 'john');
INSERT INTO `my_table` VALUES ('2011', 'dave');
INSERT INTO `my_table` VALUES ('2010', 'hany');
My question is how to add id
auto_increment
so that it can be
INSERT INTO `my_table` VALUES (1, '2011', 'john');
INSERT INTO `my_table` VALUES (2, '2011', 'dave');
INSERT INTO `my_table` VALUES (3, '2010', 'hany');
I've tired this but failed
$q1 = "ALTER TABLE `my_table` ADD COLUMN `id` int(3) NOT NULL auto_increment";
mysql_query($q1) or die(mysql_error()." at row ".__LINE__);
and given me error Incorrect table definition
so how to do it correctly.
you should add first the COLUMN
then INDEX
and then AUTO_INCREMENT
ALTER TABLE `my_table` ADD COLUMN `id` int(3) NOT NULL;
ALTER TABLE `my_table` ADD PRIMARY KEY (`id`);
ALTER TABLE `my_table` CHANGE `id` `id` INT( 3 ) NOT NULL AUTO_INCREMENT;
OR 2 queries:
ALTER TABLE my_table ADD COLUMN `id` int (3) NOT NULL;
ALTER TABLE my_table ADD PRIMARY KEY `id`(`id`), CHANGE `id` `id` INT( 3 ) NOT NULL AUTO_INCREMENT;
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