创建用户并授权
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grant all privileges on *.* to ‘www‘@‘localhost‘ identified by ‘123456‘; #授权www,所有操作，所有表权限
grant all privileges on *.* to ‘navicat‘@‘%‘ identified by ‘123456‘; #授权navicat,所有操作，所有表，所有主机权限
flush privileges; #刷新
show grants for ‘www‘@‘localhost‘; #查看权限
DROP USER ‘www‘@‘host‘;