mySQL 查询: ALTER TABLE `email2` DROP PRIMARY KEY ,
ADD PRIMARY KEY ( `adddate` ) MySQL 返回: #1075 - Incorrect table definition; there can be only one auto column and it must be defined as a key 增加一下主键竟然错误CREATE TABLE IF NOT EXISTS email2 (
emailid int(11) NOT NULL AUTO_INCREMENT,
mailto varchar(255) NOT NULL DEFAULT 'ALL',
adddate datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
PRIMARY KEY (emailid),) ENGINE=MyISAM 建好表了, 现要给这个表要加个主健, 为什么总是错
adddate datetime NOT NULL DEFAULT '0000-00-00 00:00:00',给这个adddate 加个主健
ALTER TABLE `email2` DROP PRIMARY KEY ,
ADD PRIMARY KEY ( `adddate` )
ADD PRIMARY KEY ( `adddate` ) MySQL 返回: #1075 - Incorrect table definition; there can be only one auto column and it must be defined as a key 增加一下主键竟然错误CREATE TABLE IF NOT EXISTS email2 (
emailid int(11) NOT NULL AUTO_INCREMENT,
mailto varchar(255) NOT NULL DEFAULT 'ALL',
adddate datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
PRIMARY KEY (emailid),) ENGINE=MyISAM 建好表了, 现要给这个表要加个主健, 为什么总是错
adddate datetime NOT NULL DEFAULT '0000-00-00 00:00:00',给这个adddate 加个主健
ALTER TABLE `email2` DROP PRIMARY KEY ,
ADD PRIMARY KEY ( `adddate` )
ADD PRIMARY KEY ( `adddate` ) int(11) NOT NULL AUTO_INCREMENT PRIMARY KEY COMMENT '主键';
ADD `adddate` int(11) NOT NULL AUTO_INCREMENT PRIMARY KEY COMMENT '主键';//或者ALTER TABLE `email2` CHANGE `主键名` `新主键名` int(11) NOT NULL AUTO_INCREMENT COMMENT '主键';
adddate datetime NOT NULL DEFAULT '0000-00-00 00:00:00',
ADD PRIMARY KEY ( `adddate` ) //上面那条把值全为0000-00-00 00:00:00 下面声明主键的的时候数据库重复,缺少唯一性.所以错...