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mysql用户和账号--(mysql学习二)
客户端要连接oracle只有提供用户名、密码、网络字符串就可以了
mysql客户端要连接服务器要提供账号和密码.
账号=用户名@ip;
建一个user不是建一个用户而是建一个账号,同样删除一个uesr也是删除一个账号。root是用户名,root@loaclhost是账号名.
2、mysql参数文件
可以通过mysql --help查看加载路劲(注意不能输入;.只有在mysql>下才用输入;)
文件内容大的可以分为两部分:mysqld和其他
3、常用参数:
/G
/g和';':等价
/c:取消
/q和exit:等价
显示格式:
-B、-t、-X、-H
status查看数据库设置,查看字符集。
source等同于oracle的@,文件方式执行sql.
set password for 'root'@'localhost'=password('oracle');修改设置账号密码.
4、数据库
在oracle中schame是表示一个账号下的对象的集合等价于mysql的database;
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TooptimizeMySQLperformance,followthesesteps:1)Implementproperindexingtospeedupqueries,2)UseEXPLAINtoanalyzeandoptimizequeryperformance,3)Adjustserverconfigurationsettingslikeinnodb_buffer_pool_sizeandmax_connections,4)Usepartitioningforlargetablestoi


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