6月10日学习进度

合集 - 每日汇总(31)

1.10月10日总结2023-10-102.6月9日学习进度2024-06-093.10月16日总结2023-10-164.10月17日总结2023-10-175.10月18日总结2023-10-186.JAVA项目常用异常处理汇总2023-10-197.10月19日总结2023-10-198.10月20日总结2023-10-219.6月8日学习进度2024-06-0810.10月24日总结2023-10-2411.10月25日总结2023-10-2912.10月27日总结2023-10-2913.10月26日总结2023-10-2914.10月30日总结2023-10-3015.10月31日总结2023-11-0216.11月1日总结2023-11-0217.11月2日总结2023-11-0218.11月3日总结2023-11-0319.11月6日总结2023-11-08

20.6月10日学习进度2024-06-10

21.11月13日总结2023-11-1322.11月16日总结2023-11-1923.11月20日总结2023-11-2124.11月21日总结2023-11-2125.11月22日总结2023-11-2526.11月23日总结2023-11-2527.11月27日总结2023-11-2828.11月28日总结2023-11-2829.11月29日总结2023-11-3030.11月30日总结2023-12-0631.6月13日学习进度2024-06-13

收起

一.所花时间

2h

二.代码量

100行

三.博客量

1篇

四.了解到的知识点

第四章

1.select * from SC;

2.select sname,sage from Student where sdept = ‘计算机系’;

3.select sno,cn0,grade from SC where grade between 70 and 80;

4.select sname,sage from Student where sdept = ‘计算机系’ and sage between 18 and 20;

5.select max(grade) from SC where cno = ‘c001’;

6.select max(sage) as 最大年龄,min(sage) as 最小年龄 from Student where sdept = ‘计算机系’;

7.select sdept,count(*) as 人数 from Student group by sdept;

8.select cno,count(*) as 人数,max(grade) as 最高分 from SC group by cno;

9.select sno,count(*) as 选课门数,sum(grade) as 总成绩 from SC group by sno order by count(*) asc;

10.select sno,sum(grade) as 总成绩 from SC group by sno having sum(grade)>200;

11.select s.sname,s.sdept from Student s join SC on s.sno = SC.sno where SC.cno = ‘c002’;

12.select s.sname,SC.cno,SC.grade from Student s join SC on s.sno = SC.sno where SC.grade > 80 order by grade desc;

13.select c.cno,c.cname from Course c left join SC on c.cno = SC.cno where SC.cno is null;

14.select cname, semester from Course where semester = (select semester from Course where cname = ‘Java’);

15.select s1.sname,s1.sdept,s1.sage from student s1 join student s2 on s1,sno = s2.sno where s2.sname = ‘李勇’ and s1.sname != ‘李勇’;

16.(1)select sname,sdept from Student where sno in (select from SC where cno = ‘c001’);

(2)select s.sno,s.sname,SC.cno,SC.grade from Student s join SC on s,sno = SC.sno where sdept = ‘数学系’ and sno in (select sno from SC where grade > 80);

(3)select s.sname from Student s join SC on s.sno = SC.sno where sdept =’计算机系’ and grade = (select max(grade) from SC join Student s on s.sno = SC.sno where sdept = ‘计算机系’);

(4)select s.sname,s.sdept,s.ssex,SC.grade from Student s join SC on s.sno = SC.sno join Course c on c.cno=SC.cno where cname = ‘数据结构’ and grade = (select max(grade) from SC join Course c on c.cno = SC.cno where cname = ‘数据结构’);

17.select sname,ssex from Student where sno not in (select sno from sc join Course c on c.cno = SC.cno where cname = ‘Java’);

18.select sname,ssex from Student where sno not in (select distinct sno from sc);

19.insert into test_t(COL2) values (‘B1’);

insert into test_t values (1,’B2’,’C2’);

insert into test_t(COL1,COL2) values (2,’B3’);

20.delete from SC where grade < 50;

21.delete from Course where cno not in (select distinct cno from SC);

22.delete from SC from SC join Course c on SC.cno = c.cno join Student s on SC.sno = s.sno where c.cname = ‘Java’ and SC.grade < 60 and s.sdpt = ‘计算机系’;

23.update Course set credit = credit+2 where semester = 2;

24.update Course set credit = 3 wehre cname = ‘Java’;

25.update Student set sage = sage+1 where sdept = ‘计算机系’;

26.update SC set grade = grade+5 from Student s join SC on s.sno = SC.sno join Course c on c.cno = SC.cno where s.sdept = ‘信息系’ and c.cname = ‘计算机文化学’;

27.select sdept,count(*) as 人数 into Dept_Age from Student where sage >= 20 group by sdept;