实训day2

Mysql语句

like 不加上“%”或者“_”就等于“等于”

like '%a' 查询以a结尾的
LIKE '_a%'查询第二个字符是a的  （以此类推）




自定义一个转义字符是escape




select * from user where userID not in(4,5,8) ORDER BY userID desc  按ID倒序排序


select * from user where userID not in(4,5,8) ORDER BY userID asc   按ID正序排序 


select * from user where userID not in(4,5,8) ORDER BY sex desc ，flag asc 先满足第一个条件在满足第二个条件


select password from user where userID<5   查找ID小于5的用户密码


select * from user where password like '%8%'  查找数据库中密码中间含有数字8的密码


update user set password='11111' where userID=5  修改数据库中ID为5的用户密码为111111


select * from user where password like '_8%'  选出数据库中密码第二位为8的用户


insert into user(username,password,sex,flag) values('qweqweqwe','222','1','1')   添加用户qweqweqwe,密码为222，男性，flag为1的数据


select * from user where password like '%7_'  查找数据库中用户密码倒数第二位为数字7的用户


insert into user(username,password,sex,flag) values('username','%312','1','3')  添加用户名为username,密码为%312，男性，flag为3的数据


select * from user where password like '%\%%'  查找数据库中用户密码中间含有%号的用户


select * from user where password like '\%%'


select * from user where userID not in(4,5,8) ORDER BY sex desc ，flag asc


select * from user where userID not in(4,5,8) ORDER BY userID desc 


select * from user where userID not in(4,5,8) ORDER BY userID asc


select * from user where password not like '\%%'


delete from user where userID=2  删除用户ID 为2的数据


select * from user where password like '\%%' or '%\%%'


select * from user where userID =4 or userID=5 or userID=7


select * from user where userID in (4,5,7)


select * from user where userID not in (4,5,7)


delete from user where userID=7


insert into user (username,password,sex,flag) values('sdfs','qwe11','0','1')