create user 'cai'@'localhost' identified by 'cai111';
create user 'caicai'@'localhost' identified by 'cai111';
select user,password,host from mysql.user;
drop user 'cai'@'%';
drop user 'cai'@'localhost
select user();
select current_user();
show grants;
show processlist;
delete from mysql.user where host='127.0.0.1' or host='localhost.localdomain';
flush privileges;
drop user 'caiyinliang'@'localhost';
select user,password,host from mysql.user;
create user 'caiyinliang'@'%' identified by 'cai111';
show grants for caiyinliang@'%';
grant select on test.* to 'caiyinliang'@'%' identified by 'cai111';