SQL高级 第五章 我的租房网

use HOUSEselect * from hos_house  --房间信息表select * from hos_district  --区县表select * from hos_street    --街道表select * from hos_type    --房间类型表--1.内容扩充：临时表--如果表名前面有#，那么创建的表是临时表，位于tempdb数据库下--的临时表文件夹下。create table #mytemp2222(  id int identity(1,1) primary key not null,  name nvarchar(20))  --使用临时表的好处：临时表中的数据当我们断开连接后自动释放，这样  --可以节省数据库服务器的空间--任务一：分页显示查询出租房信息--经典分页思路(一、双top，双order by 二、Row_number()函数  三、临时表方式(和Row_Number()原理一致))--将出租房屋记录批量插入临时表--*******************方式一：双top，双order by分页************************--查询输出第6条~第10条房屋出租信息--did:区县编号(hos_district)select top 5 *,hos_district.didfrom hos_house,hos_street,hos_districtwhere  hmidnot in(select top 5 hmid from hos_house)and hos_house.sid=hos_street.sidand hos_street.sdid=hos_district.did--*******************方式二：Row_Number() over(order by id)***************select * from (select *,row_number() over(order by hmid) as myidfrom hos_house) as tempwhere myid between 6 and 10--*******************方式三：临时表分页***********************************--查询输出第6条~第10条房屋出租信息use houseselect identity(int,1,1) as myid, UID, SID, HTID, PRICE, TOPIC, CONTENTS, HTIME, COPYinto #housetempfrom hos_house--通过临时表我们发现，其实实现分页只有两中思路，一种是通过双top，双order by方式，--另外一种方式就是用一定的手段(可以使系统提供Row_NUmber()函数，也--可以通过identity(int,1,1)来产生)，在现有表上加上一个自动增长列。select * from #housetempwhere myid between 6 and 10--如何将临时表释放drop table #housetemp--练习2——查询指定客户发布的出租房屋信息--需求说明::--查询“张三”发布的所有出租房屋信息，并显示房屋分布的   街道、区县select DNAME as 区县,SNAME as 街道,HTNAME as 户型,price as 价格,topic as 标题,contents as 描述,htime as 时间,copy as 备注from hos_district,hos_street,hos_type,hos_housewhere hos_house.sid=hos_street.sidand hos_house.htid=hos_type.htidand hos_street.sdid=hos_district.didand uid=(  select uid from sys_user   where uname='张三')--阶段3：练习——按区县制作房屋出租清单--根据户型和房屋所在区县和街道,为至少有2个街道有房屋出租的区县制作出租房屋清单--方式一(推荐)：select HTNAME as 户型,UNAME as 姓名,DNAME as 区县, SNAME as 街道from hos_type,sys_user,hos_district,hos_street,hos_housewhere hos_house.sid=hos_street.sidand hos_type.htid=hos_house.htidand sys_user.uid=hos_house.uidand hos_district.did=hos_street.sdidand hos_street.sdid in(  select  hos_street.sdid  from  hos_street,hos_district,  (select distinct sid from hos_house) as temp  where hos_street.sid=temp.sid  and hos_street.sdid=hos_district.did  group by hos_street.sdid  having count(hos_street.sid)>=2)--方式二：select HTNAME as 户型,UNAME as 姓名,DNAME as 区县, SNAME as 街道from hos_type,sys_user,hos_district,hos_street,hos_housewhere hos_house.sid=hos_street.sidand hos_type.htid=hos_house.htidand sys_user.uid=hos_house.uidand hos_district.did=hos_street.sdidand hos_house.SID in(  select hos_street.SID  from hos_street  where sdid in  (    select sdid    from hos_street,(select distinct(SID) from hos_house) as temp   where hos_street.sid=temp.sid   group by sdid  having count(hos_street.SID)>=2  ))--阶段4：按季度统计本年发布的房屋出租数量--要求输出本年1月1日至今的全部出租房屋数量，各区县--出租房屋数量以及各街道、户型出租房屋数量。use houseDECLARE @year int--SET @year = DATEPART(yy,GETDATE())set @year=2009SELECT tmp.quarter AS '季度',hos_district.DNAME AS '区县',hos_street.SNAME AS '街道',hos_type.HTNAME AS '户型',tmp.cnt AS '房屋数量'FROM (  SELECT SID,HTID,COUNT(*) cnt,DATEPART(qq,HTIME) quarter  FROM hos_house  WHERE DATEPART(yy,HTIME)=@year  GROUP BY DATEPART(qq,HTIME),SID,HTID) tmp--INNER JOIN sys_user ON (tmp.UID=sys_user.UID)INNER JOIN hos_street ON(tmp.SID=hos_street.SID)INNER JOIN hos_district ON(hos_street.SDID=hos_district.DID)INNER JOIN hos_type ON(tmp.HTID=hos_type.HTID)UNIONSELECT DATEPART(qq,HTIME),hos_district.DNAME,' 小计 ','  ',COUNT(*) AS '房屋数量'FROM hos_houseINNER JOIN hos_street ON(hos_house.SID=hos_street.SID)INNER JOIN hos_district ON(hos_street.SDID=hos_district.DID)WHERE DATEPART(yy,HTIME)=@yearGROUP BY DATEPART(qq,HTIME),hos_district.DNAMEunionSELECT DATEPART(qq,HTIME),' 合计 ','  ','  ',COUNT(*) AS '房屋数量'FROM hos_houseWHERE DATEPART(yy,HTIME)=@yearGROUP BY DATEPART(qq,HTIME)