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SELECT * from products WHERE id='3' FOR UPDATE;
Àý2: (Ã÷È·Ö¸¶¨Ö÷¼ü£¬Èô²éÎ޴˱Ê×ÊÁÏ£¬ÎÞlock)
SELECT * from products WHERE id='-1' FOR UPDATE;
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SELECT * from products WHERE name='Mouse' FOR UPDATE;
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SELECT * from products WHERE id<>'3' FOR UPDATE;
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SELECT * from products WHERE id LIKE '3' FOR UPDATE;
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MySQLѧϰ(5)IN,GRANT,MD5,EXISTS

1.INµÄÓ÷¨
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NOT IN(value,..)ºÍINÓï·¨Ò»Ñù¡£
2.IF NOT EXISTS
CREATE ... IF NOT EXISTS stm; ...¿ÉÒÔʹDATABASE,TABLE,EVENT¡£ÈçCREATE TABLE IF NOT EXISTS t(id INT); 
3.MD5,MySQLÊý¾Ý¿âÌṩÁËmd5¼ÓÃܹ¦Ä ......

windowsµÄ64λƽ̨railsÁ¬½ÓmysqlµÄ·½·¨


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gem install mysql
ʹÓÃmysql£¬È磬rake db:migrate
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E:\study\ruby\rails_space>rake db:migrate
(in E:/study/ruby/rails_space)
!!! The bundled mysql.rb driver has been removed from Rails 2.2. Please install the mysql gem and try again: gem install mysql.
rake aborted!
193: ......

JDBCÁ¬½ÓMySQLÊý¾Ý¿âʵÏÖÔöɾ²é¸Ä

package com.qll.operate;
import java.sql.*;
public class OperateUser {
 String driver = "com.mysql.jdbc.Driver";
 String url = "jdbc:mysql://localhost:3306/test";
 String name = "root";
 String password = "123456";
 static Connection conn = null;
 Statement st = ......
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