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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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£¨1£©select count(*) from `user`
£¨2£©select count(name) from `user`
£¨3£©select count(password) from `user`
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# mysql -uroot -p
Enter password:
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
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# mysqladmin -uroot -p password 'newpassword'
Enter pass ......

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GRANT ALL PRIVILEGES ON *.* TO 'root'@'ÄãµÄÔ¶¶Ëip' IDENTIFIED BY 'ÄãµÄÃÜÂë' WITH GRANT OPTION;
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GRANT ALL PRIVILEGES ON *.* TO 'root'@'10.10.19.220' IDENTIFIED BY '123456' WITH GRANT OPTION;
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CREATE TABLE `test1` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `name` varchar(20) NOT NULL,
  `desc` varchar(100) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
£¨1£©ÒÔϲéѯ»á±¨´íÎó£º[Err] 1221 - Incorrect usage of UNION and ORDE ......
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