实验六使用T-SQL语句查询数据

一．实验目的：

熟练掌握使用SELECT语句进行数据查询。

二．实验内容：（所有题写到实验报告中）

1.对数据库stuinfo使用T-SQL命令进行如下操作：

查询student表中的学号、姓名和年龄并为列设置别名，结果按学号升序排。

USE stuinfo;
SELECT sno AS 学号, sname AS 姓名, YEAR(GETDATE()) - YEAR(sbirthday) AS 年龄 FROM student ORDER BY sno;

查询班级（要求不重复）。

SELECT DISTINCT sclass AS 班级 FROM student;

查询姓“王”的学生信息。

SELECT * FROM student WHERE sname LIKE '王%';

查询成绩在80-100之间的学号、课程号及成绩，结果先按课程号升序排，课程号一样的再按成绩降序排。

SELECT sno AS 学号, cno AS 课程号, degree AS 成绩 FROM score WHERE degree >= 80 AND degree <= 100 ORDER BY cno ASC, degree DESC;

查询所有缺考的学生的学号及课程号。

SELECT sno AS 学号, cno AS 课程号 FROM score WHERE degree is NULL;

查询 ‘3-105’课的选课人数、最高分、最低分和平均分。

SELECT COUNT(*) AS 选课人数, MAX(degree) AS 最高分 , MIN(degree) AS 最低分, AVG(degree) AS 平均分 FROM score where cno = '3-105';

查询每位同学的平均成绩，包括学号和平均成绩两列，结果按学号升序排。

SELECT sno AS 学号, AVG(degree) AS 平均成绩 FROM score GROUP BY sno ORDER BY sno;

查询各班各门课的平均成绩，包括班号、课程号和平均成绩三列，结果先按班升序排，班一样的再按课程号升序排。

SELECT AVG(degree) AS 平均成绩, sclass AS 班号, cno AS 课程号 FROM score, student WHERE score.sno = student.sno GROUP BY sclass, cno ORDER BY sclass ASC, cno ASC;

查询score表中至少有5名学生选修的课程号及平均分。

SELECT cno AS 课程号, AVG(degree) AS 平均分 FROM score GROUP BY cno HAVING COUNT(*) >= 5;

查询其平均分高于80的学生的学号，姓名和平均分。

SELECT student.sno, sname, AVG(degree) AS avg FROM score, student WHERE student.sno = score.sno GROUP BY student.sno,sname HAVING AVG(degree) > 80;

查询“95031”班所选课程的平均分，包括课程名和平均分。

SELECT cname, AVG(degree) AS avg FROM course, score, student WHERE course.cno = score.cno AND score.sno = student.sno AND student.sclass = '95031' GROUP BY score.cno, cname;

查询所有教师的任课情况，包括教师姓名和课程名两列，如果某位教师没有任课则课程名列显示NULL。

SELECT tname, cname FROM teacher LEFT JOIN  course ON teacher.tno = course.tno;

查询其最低分大于70，最高分小于90的学生的学号、所选课程号及其分数。

SELECT sno, cno, degree FROM score WHERE sno in (SELECT sno FROM score  group by sno having MIN(degree) > 70 )  AND sno in (SELECT sno FROM score  group by sno having MAX(degree) < 90 )
# 没有满足条件的行，故无截图

查询成绩高于所选课平均分的学生学号、姓名、课程号和成绩。

SELECT student.sno,sname, cno, degree FROM student, score a WHERE student.sno = a.sno AND degree > (SELECT AVG(degree) FROM score b WHERE a.cno = b.cno);

查询每门课最高分的课程名、学生姓名和成绩。

SELECT cname, sname, degree FROM student, course, score a WHERE student.sno = a.sno AND course.cno = a.cno AND degree = (SELECT MAX(degree) FROM score b WHERE b.cno = a.cno);

查询选修其课程的学生人数多于5人的教师姓名。

SELECT tname FROM teacher, course WHERE teacher.tno = course.tno AND (SELECT COUNT(*) FROM score WHERE score.cno = course.cno) > 5;
# 无符合条件的，不附截图

查询没选“张旭”教师课的学生成绩，并按成绩递增排列。

SELECT degree FROM score WHERE score.cno NOT IN (SELECT course.cno FROM course, teacher WHERE teacher.tname = '张旭' AND course.tno = teacher.tno) ORDER BY degree;

查询没有任课的教师的姓名。

SELECT tname FROM teacher EXCEPT SELECT tname FROM teacher,course WHERE teacher.tno=course.tno;

查询没有选修"6-166"课程的学生的学号和姓名。

SELECT student.sno, student.sname FROM student WHERE student.sno NOT IN (SELECT sno FROM score WHERE cno = '1-166');

查询出所有男生信息放入NS表中。

SELECT  student.sno AS 学号, student.sname AS 学生姓名, ssex AS 性别, sbirthday AS 生日, sclass AS 班级, cname AS 课程
, degree AS 成绩 INTO NS FROM student, score, course WHERE student.sno = score.sno AND ssex = '男' AND course.cno = score.cno;

删除没人选的课程。

DELETE FROM course WHERE cno NOT IN(SELECT cno FROM score GROUP BY cno);
# 删除不附截图

将“95031”班学生的成绩全部减去10分。

UPDATE score SET degree = degree - 10 WHERE score.sno IN (SELECT sno FROM student WHERE sclass = '95031');

对订单管理库ordermanagement使用T-SQL命令进行下列查询。

ordermanagement数据库中有三个表，其结构如下：（加下划线的为主键）
客户表customer(客户号，客户名，地址，电话)
订单表order_list(订单号，客户号，订购日期)
订单明细表Order_detail(订单号，器件号，器件名，单价，数量)
使用SELECT语句完成下列查询：

查询2001年的所有订单信息（订单号，客户号，订购日期）。

USE OrderManagement
SELECT 订单号, 客户号, 订购日期 FROM order_list;

2) 查询订单明细中有哪些器件（即查询不重复的器件号和器件名）。

SELECT DISTINCT 器件号, 器件名 FROM order_detail;

查询客户名为“三益贸易公司”的订购单明细（订单号、器件号、器件名、单价和数量），
查询结果先按“订单号”升序排，同一订单的再按“单价”降序排。

SELECT order_detail.订单号, 器件号, 器件名, 单价, 数量 FROM order_detail, customer, order_list WHERE customer.客户号 = order_list.客户号 AND order_list.订单号 = order_detail.订单号 AND customer.客户名 = '三益贸易公司' ORDER BY order_detail.订单号, 单价 DESC;

4) 查询目前没有订单的客户信息。

SELECT * FROM customer WHERE 客户号 NOT IN(SELECT 客户号 FROM order_list);

查询客户名中有“科技”字样的客户信息。

SELECT * FROM customer WHERE 客户名 LIKE '%科技%';

6) 查询每笔订单的订单号和总金额，查询结果按订单号升序排，查询结果存入表ZJE中。

SELECT 订单号, SUM(单价 * 数量) AS 总金额 INTO ZJE FROM order_detail GROUP BY order_detail.订单号 ORDER BY order_detail.订单号;

查询订单数量超过5笔的客户号及订单数量，查询结果按订单数量降序排。

SELECT 客户号, COUNT(订单号) AS 订单数量 FROM order_list GROUP BY 客户号 HAVING COUNT(订单号) > 5 ORDER BY 订单数量 DESC;

查询每种器件中单价最低的订单明细（订单号、器件号、器件名、单价和数量）。

SELECT * FROM order_detail a WHERE 单价 IN (SELECT MIN(单价) FROM order_detail b WHERE a.器件名 = b.器件名);

对表order_detail建立查询，把“订单号”的尾部字母相同且“器件号”相同的订单合并
成一张订单，新的“订单号”取原来订单号的尾部字母，器件号不变，“单价”取最低价，
“数量”取合计，查询结果先按新的“订单号”升序排，再按“器件号”升序排。

SELECT RIGHT(order_detail.订单号,1) AS 订单号, 器件号, MIN(单价) AS 单价, SUM(数量) AS 数量 FROM order_detail GROUP BY order_detail.订单号, 器件号 ORDER BY 订单号,器件号;

10) 查询销售总数量最多的三种器件及其总数量。

SELECT TOP 3 器件号, 器件名, SUM(数量) AS 数量 FROM order_detail GROUP BY 器件号,器件名 ORDER BY 数量 DESC;