创建QQ数据库
#创建数据库 CREATE DATABASE QQ #创建表名 并且添加列 DROP TABLE IF EXISTS `dbo.BaseInfo`; CREATE TABLE `student`( QQID INT PRIMARY KEY AUTO_INCREMENT, NickName VARCHAR(32), Sex INT, Age INT , Province VARCHAR(256), City VARCHAR(32), Address VARCHAR(32), Phone INT ) #修改表名 ALTER TABLE student RENAME BaseInfo #添加BaseInfo表qq表的信息数据 INSERT INTO student (QQID,NickName,Sex,Age,Province,City,Address,Phone)VALUES (8855678,‘独行侠‘,1,38,‘北京‘,‘海淀区‘,‘上地‘,003), (54789625,‘蝴蝶飞飞‘,1,16,‘北京‘,‘朝阳区‘,‘亚运村‘,001), (88662753,‘青青草‘,0,20,‘河南省‘,‘安阳‘,‘汤阴‘,002); #创建QQUser表并且添加列 CREATE TABLE `QQUser`( QQID INT PRIMARY KEY AUTO_INCREMENT, PASSWORD VARCHAR(32), LastLogTime DATETIME, OnLine INT , LEVEL INT ) #添加QQUser表的信息数据 INSERT INTO QQUser (QQID,PASSWORD,LastLogTime,OnLine,LEVEL)VALUES (8855678,‘guest0221‘,‘2008-02-21 16:28:20:000‘,1,6), (54789625,‘add521#&‘,‘2008-02-16 17:01:35:000‘,2,1), (88662753,‘admin0219‘,‘2008-02-19 21:08:35:000‘,0,5); #删除表名 DROP TABLE QQUser #创建QQUser表并且添加列 CREATE TABLE `Relation`( QQID INT , RelationQQID INT, RelationStalus INT ) #添加QQUser表的信息数据 INSERT INTO Relation (QQID,RelationQQID,RelationStalus)VALUES (54789625,88662753,0), (88662753,8855678,1), (54789625,8855678,0);
01.查询QQ号码为54789625的所有好友信息,包括QQ号码,昵称,年龄 SELECT QQID,NickName,Age FROM baseinfo WHERE QQID =54789625 #02.查询当前在线用户的信息 SELECT *FROM qquser WHERE OnLine!=0 #03.查询北京的、年龄在18至45岁之间的在线用户的信息 SELECT *FROM baseinfo,qquser WHERE baseinfo.QQID =qquser.QQID AND baseinfo.Province=‘北京‘ AND baseinfo.Age BETWEEN 18 AND 45 AND qquser.OnLine>0 #04.查询昵称为青青草的用户信息 SELECT *FROM baseinfo WHERE NickName=‘青青草‘ #05.查询QQ号码为54789625的用户的好友中每个省份的总人数,并且总人数按由大到小排序。 SELECT COUNT(Province) FROM baseinfo WHERE QQID IN ( SELECT QQID FROM relation WHERE RelationQQID IN( SELECT RelationQQID FROM relation WHERE QQID =‘54789625‘ ) ) GROUP BY Province #06.查询至少有150天未登录QQ账号的用户信息,包括QQ号码,最后一次登录时间、等级、昵称、年龄,并按时间的降序排列 SELECT qquser.QQID, LastLogTime,LEVEL,NickName,Age FROM baseinfo,qquser WHERE baseinfo.QQID=qquser.QQID AND baseinfo.QQID IN( SELECT QQID FROM qquser WHERE DATEDIFF(NOW(),LastLogTime ) >=150 ) GROUP BY LastLogTime #07.查询QQ号码为54789625的好友中等级为10级以上的“月亮”级用户信息。 SELECT *FROM baseinfo WHERE QQID IN(SELECT QQID FROM qquser WHERE LEVEL>10 AND QQID IN( SELECT QQID FROM relation WHERE RelationQQID IN ( SELECT RelationQQID FROM relation WHERE QQID =‘54789625‘ ))) #08.--查询QQ号码为54789625的好友中隐身的用户信息。 SELECT *FROM baseinfo WHERE QQID IN (SELECT QQID FROM qquser WHERE OnLine=0 AND QQID IN ( SELECT QQID FROM relation WHERE RelationQQID IN ( SELECT RelationQQID FROM relation WHERE QQID =‘54789625‘ ))) #09.--查询好友超过20个的用户信息。 SELECT *FROM baseinfo WHERE QQID IN ( SELECT QQID FROM relation WHERE RelationQQID IN( SELECT RelationQQID FROM relation GROUP BY QQID HAVING COUNT(RelationQQID)>20) ) #10.为了查看信誉度,管理员需要查询被当做黑名单人物次数排名前3的用户 SELECT * FROM baseinfo WHERE baseinfo.QQID IN( SELECT qquser.QQID FROM qquser WHERE baseinfo.QQID=qquser.QQID AND qquser.QQID IN( SELECT relation.QQID FROM relation WHERE relation.RelationStalus=1 ) ORDER BY qquser.Level DESC ) LIMIT 3 ##用例2:修改数据 #01.假设我的QQ号码为8855678,今天我隐身登录 UPDATE qquser SET OnLine=‘0‘ WHERE QQID =‘8855678‘ #02.假设我的QQ号码为8855678,修改我的昵称为“被淹死的鱼”,地址为“解放中路号院123室” UPDATE baseinfo SET NickName=‘被淹死的鱼‘,Address =‘解放中路号院123室‘ WHERE QQID=‘8855678‘ #03.假设我的QQ号码为54789625,将我的好友“青青草”拖进黑名单。 UPDATE relation SET RelationStalus =1 WHERE QQID =‘54789625‘ #04.为了提高QQ用户的聊天积极性,把等级小于6级的用户的等级都提升1个级别。 UPDATE qquser SET LEVEL =LEVEL+1 WHERE LEVEL<6 #05.管理员将超过365天没有登录过的QQ锁定(即将等级值设定为-1)。 UPDATE qquser SET LEVEL =-1 WHERE DATEDIFF(NOW(),LastLogTime ) >=365 #06.为了奖励用户,将好友数量超过20的用户等级提升1个级别。 UPDATE qquser SET LEVEL=LEVEL+1 WHERE ( SELECT RelationQQID FROM relation GROUP BY QQID HAVING COUNT(RelationQQID)>20) #07.把QQ号码为54789625的用户的好友“嘟嘟鱼”拖进黑名单中。 UPDATE relation SET RelationStalus =1 WHERE QQID =‘54789625‘ ##用例3:删除数据 #1.把QQ号码为54789625的用户黑名单中的用户删除。 DELETE FROM relation WHERE QQID=‘54789625‘ #2.QQ号码为54789625的用户多次在QQ中发布违法信息,造成了很坏的影响,因此管理员决定将其删除。 DELETE FROM baseinfo WHERE QQID =‘54789625‘ #3.管理员将超过1000天没有登录过的QQ删除。 UPDATE FROM qquser WHERE DATEDIFF(NOW(),LastLogTime ) >=1000