授权命令：
1.全部权限：grant all on *.* to user@192.168.10.2 identified by "pass"；
2.部分权限：grant select,insert into on *.* to user@192.168.10.2 identified by "pass"
查看用户授权表：
select user,host,password from mysql.user;
mysql下默认存在mysql数据库，里边的user表存储着用户和授权信息。
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遇到的问题：本地的navicat链接不上我虚拟机的mysql
解决：需要虚拟机的mysql授权给本地的ip：grant all on *.* to user@192.168.64.21 identified by "pass"；