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CREATE TABLE `user` (
  `id` int(5) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(10) DEFAULT NULL,
  `password` varchar(10) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=4 DEFAULT CHARSET=latin1
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1 name1 123456
2 name2 123456
3 name3 123456
4 name4  NULL
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£¨3£©select count(password) from `user`
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create table 't_user' (
    'id' int(11) not null auto_increment,
    'name' varchar(100) not null default '',
    primary key ('id')
) type=myisam;
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