数据库作业-sql语句查询

建表的插入数据的表

-- 1. 查询全部商品信息。 SELECt * from goods

-- 2．查询类别为“cn002”的所有商品信息。 SELECt * from goods JOIN category on goods.categoryno = category.categoryno where goods.categoryno ="cn002" -- 3. 查询类别为“cn001”和“cn002”对应的所有商品信息。 select * from category join goods on  category.categoryno=goods.categoryno where category.categoryno like 'cn00[1-2]'; -- 4．查询类别为“cn005”且进价大于 20 的商品信息。 SELECt * from goods WHERe goods.categoryno="cn005" and goods.inprice >20 -- 5．查询库存数量小于 10 的商品号，供应商号，商品名和数量。 SELECt g.goodsno,g.goodsname,g.supplierno,g.number from goods as g where g.number <10 -- 6．查询有购买记录学生的学号。 SELECt DISTINCT s.sno  from salebill as s

-- 7．查询计算机专业“IT”学生的学号，姓名和年龄 SELECt s.sno,s.sname,2022-s.birthyear as age from student as s WHERe s.major ='IT' -- 8．查询年龄在 22 到 24 岁学生的学号，姓名，学院，专业和年龄 SELECt s.sno,s.sname,s.college,s.major,2022-s.birthyear as age from student  as s where 2022-s.birthyear BETWEEN 22 and 24

-- 9． 查询姓张的同学的学号，姓名，学院。 SELECt s.sno,s.sname,s.college from student as s where s.sname like "张%" -- 10．查询库存数量在 20 以上的商品信息，并按数量的降序排列。 SELECt * from goods as g where g.number >20 order by g.number desc -- 11．查询库存数量在 10 以内的商品编号、商品名称、类别号、数量，按类别升序库存数量降序排列结果。 SELECt g.goodsno,g.goodsname,g.categoryno,g.number from goods as g where g.number BETWEEN 6 and 13 ORDER BY g.categoryno ,g.number desc

-- 12．查询库存数量排名前三的商品信息。 SELECt  * from goods as g order by g.number DESC limit 3 -- 13. 查询类别为“cn001”库存数量最大的商品，显示商品号，商品名和数量 SELECt  * from goods as g order by g.number DESC limit 1 -- 14．查询管理信息系统专业“MIS”的学生人数。 SELECt count(*) from student as s where s.major ="MIS" -- 15．按学院统计各个学院，年龄在 20 岁以上的学生人数。 SELECt s.college,count(*) from student as s where 2022-s.birthyear >20 GROUP BY s.college -- 16．统计 2018 年各商品的销售总量。 SELECt g.goodsname,sum(s.number) as 销售总量 from   goods  as g join   salebill as s on  g.goodsno = s.goodsno  where s.happentime between '2018/01/01' and '2018/12/31'  GROUP BY s.goodsno -- 17．查询学生人数在 3 人以上的学院及学生人数。

SELECt s.college,count(*) from student  as s GROUP BY s.college HAVINg count(s.college) >3 -- 18．查询 2019 年商品购买总数在 5 以上的学生的学号和购买总数。 SELECt student.sno,count(*) as 购买总数 from student  join salebill on student.sno=salebill.sno where salebill.happentime between '2019/01/01' and '2019/12/31' group by student.sno HAVINg 购买总数>5 -- 19．查询咖啡类商品的平均售价。 SELECt goods.goodsname,avg(goods.saleprice)as 平均售价 from goods join category on goods.categoryno=category.categoryno  where category.categoryname ="咖啡" -- 20．查询与张小红同学院的学生的学号、姓名、学院。 SELECt s.sno,s.sname,s.college from student  as s   where  s.college in  ( SELECt student.college from student where student.sname = "张小红") and s.sname!="张小红" -- 21．查询所有商品的销售情况，包括商品号，商品名，学生姓名，销售时间，销售数量，按销售日期降序排列。

select goods.goodsno,goodsname,student.sname,happentime,salebill.number from goods  join salebill on goods.goodsno=salebill.goodsno  join student on salebill.sno=student.sno order by happentime desc

-- 22．查询购买了商品的学生学号、姓名、学院。 SELECt DISTINCT s.sno,s.sname,s.college from student as s join salebill  as b on s.sno= b.sno 

--23 查询购买了咖啡类商品的学生的学号、姓名、学院 select SNO,SName,College from Student where SNO in (select SNO from SaleBill where GoodsNO in  (select GoodsNO from Goods where GoodsName like '%咖啡%'))

--24查询没有出售过的商品号，商品名，类别名、售价和数量。（连接查询和子查询） select Goods.GoodsNO,GoodsName,Categoryname,Saleprice,number  from Goods join Category on Goods.CategoryNO=Category.CategoryNO where Goods.GoodsNO not in( select Goods.GoodsNO from Goods join SaleBill on Goods.GoodsNO=SaleBill.GoodsNO ) --25 查询购买了商品号为“gn001”或“gn002”商品的学号，姓名和学院。 select Student.SNO,SName,college from Goods join SaleBill on Goods.GoodsNO=SaleBill.GoodsNO join Student on Student.SNO=SaleBill.SNO where Goods.GoodsNO like 'gn00[1-2]'; --26. 查询购买了商品号为“gn001”和“gn002”商品的学号，姓名和学院。 select SNO,SName,College from Student where SNO in (select SNO from SaleBill where GoodsNO='GN001') and Student.SNO in(select SNO from SaleBill where GoodsNO='GN002') --27. 查询各学院年龄最大的学生，显示学号，姓名和学院。（相关子查询和派生表） select SNO,SName,College from Student s  where (YEAR(getdate())-YEAR(birthyear))=(select MAX(YEAR(getdate())-YEAR(birthyear))  from student where s.college = student.college)

--28. 统计每个商品的销售总数，要求显示商品号，商品名和销售总数。

select Goods.GoodsNO,GoodsName,sum(SaleBill.Number) as 销售总数 from Goods,SaleBill  where Goods.GoodsNO = SaleBill.GoodsNO group by Goods.GoodsNO,GoodsName