From b33907d577fc439398be8e454c6d84b8c90f17bd Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E7=8E=8B=E9=9B=AA=E5=BD=B1=E7=9A=84=E4=BD=9C=E4=B8=9A?= <2156239329@qq.com> Date: Sun, 22 Oct 2023 23:36:41 +0800 Subject: [PATCH] =?UTF-8?q?=E7=8E=8B=E9=9B=AA=E5=BD=B1=E7=9A=84=E4=BD=9C?= =?UTF-8?q?=E4=B8=9A?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...\347\273\217\345\205\27050\351\242\230.md" | 212 ++++++++++++++++++ 1 file changed, 212 insertions(+) create mode 100644 "39 \347\216\213\351\233\252\345\275\261/20231020 \346\225\260\346\215\256\345\272\223\347\273\217\345\205\27050\351\242\230.md" diff --git "a/39 \347\216\213\351\233\252\345\275\261/20231020 \346\225\260\346\215\256\345\272\223\347\273\217\345\205\27050\351\242\230.md" "b/39 \347\216\213\351\233\252\345\275\261/20231020 \346\225\260\346\215\256\345\272\223\347\273\217\345\205\27050\351\242\230.md" new file mode 100644 index 0000000..2b5df6b --- /dev/null +++ "b/39 \347\216\213\351\233\252\345\275\261/20231020 \346\225\260\346\215\256\345\272\223\347\273\217\345\205\27050\351\242\230.md" @@ -0,0 +1,212 @@ +```sql + + + + +-- 1. 查询" 1 "课程比" 2 "课程成绩高的学生的信息（学号、姓名、性别、出生日期）及课程分数 + +with +a as (select student.student_id 学号,student_name 姓名,gender 性别,birthday 出生日期,score 课程分数 from score join student on score.student_id=student.student_id where course_id=1), +b as (select student.student_id 学号,student_name 姓名,gender 性别,birthday 出生日期,score 课程分数 from score join student on score.student_id=student.student_id where course_id=2) +select * from a join b on a.学号=b.学号 where a.课程分数>b.课程分数; + +-- 2. 查询同时参与" 1 "课程和" 2 "课程考试的学生信息 + +SELECT * from student where student_id in +(SELECT s.student_id from score s,score ss WHERE s.student_id=ss.student_id and s.course_id=1 and ss.course_id=2); + +-- 3. 查询存在" 1 "课程但可能不存在" 2 "课程的情况(不存在时显示为 null ) + +-- 4. 查询不存在" 1 "课程但存在" 2 "课程的情况 +SELECT DISTINCT * from score s,score ss WHERE s.student_id=ss.student_id and s.course_id!=1 and ss.course_id=2; +-- 5. 查询平均成绩大于等于 60 分的同学的学生编号、姓名和平均成绩 +with a as( +select distinct student.student_id 学生编号,student_name 姓名,avg(score) over(partition by score.student_id) 平均成绩 from student join score on student.student_id=score.student_id ) +select * from a where 平均成绩>60; + +-- 6. 查询在成绩表存在成绩的学生信息 +select distinct student.* from student join score on student.student_id=score.student_id where score is not null; +-- 7. 查询所有同学的学生编号、学生姓名、选课总数、所有课程的总成绩(没成绩的显示为 null ) + +select distinct student.student_id 学生编号,student.student_name 学生姓名,count(score.course_id) over(partition by score.student_id) 选课总数,sum(score.score) over(partition by score.student_id) 总成绩 from student left join score on student.student_id=score.student_id left join course on score.course_id=course.course_id; + +-- 8. 查询「李」姓老师的数量 + +select count(*) from teacher where teacher_name like '李%'; + +-- 9. 查询学过「李白」老师授课的同学的信息 + +select teacher_id from teacher where teacher_name='李白'; +select student.* from student left join score on student.student_id=score.student_id left join course on score.course_id=course.course_id where course.teacher_id=(select teacher_id from teacher where teacher_name='李白'); + +-- 10. 查询没有学全所有课程的同学的信息 +with a as( +select distinct student.student_id 学生编号,student.student_name 学生姓名,birthday 学生生日,gender 学生性别,count(score.course_id) over(partition by score.student_id) 选课总数,sum(score.score) over(partition by score.student_id) 总成绩 from student left join score on student.student_id=score.student_id left join course on score.course_id=course.course_id) +select 学生编号,学生姓名,学生生日,学生性别,选课总数 from a where 选课总数 in(0,1,2); + +-- 11. 查询至少有一门课与学号为" 1 "的同学所学相同的同学的信息 + +select course_id from score where student_id=1; +select * from student join score on student.student_id=score.student_id where course_id in(select course_id from score where student_id=1); + +-- 12. 查询和" 1 "号的同学学习的课程完全相同的其他同学的信息 + +select * from student join score on student.student_id=score.student_id where course_id=all(select course_id from score where student_id=1); + +-- 13. 查询没学过「李白」老师讲授的任一门课程的学生姓名 + +select teacher_id from teacher where teacher_name='李白'; +select course_id from course where teacher_id=(select teacher_id from teacher where teacher_name='李白'); +-- 学过的 +select student_name from student join score on student.student_id=score.student_id where course_id =(select course_id from course where teacher_id=(select teacher_id from teacher where teacher_name='李白')); +-- 没学过的 +select student_name from student where student_name not in (select student_name from student join score on student.student_id=score.student_id where course_id =(select course_id from course where teacher_id=(select teacher_id from teacher where teacher_name='李白'))); + +-- 14. 查询两门及其以上不及格课程的同学的学号，姓名及其平均成绩 + +select distinct student.student_id 学号,student_name 姓名,avg(score) over(partition by score.student_id) 平均成绩,count(course_id) over(partition by score.student_id) 不及格课程总数 from score join student on score.student_id=student.student_id where score<60; + +-- 15. 检索" 1 "课程分数小于 60，按分数降序排列的学生信息 + +select * from score join student on score.student_id=student.student_id where course_id=1 and score<60 order by score desc; + +-- 16. 按平均成绩从高到低显示所有学生的所有课程的成绩以及平均成绩 + +select student.student_name,course.course_id,score,avg(score) over(partition by student.student_id) 平均成绩 from student left join score on student.student_id=score.student_id left join course on score.course_id=course.course_id order by 平均成绩 desc; + +-- 17. 查询各科成绩最高分、最低分和平均分 + + select distinct course_id,max(score) over(partition by course_id) 最高分,min(score) over(partition by course_id) 最低分,avg(score) over(partition by course_id) 平均分 from score; + +-- 18. 以如下形式显示：课程 ID，课程 name，最高分，最低分，平均分，及格率，中等率，优良率，优秀率（及格为>=60，中等为：70-80，优良为：80-90，优秀为：>=90），要求输出课程号和选修人数，查询结果按人数降序排列，若人数相同，按课程号升序排列 + +SELECT DISTINCT + course.course_id 课程ID, + course_name 课程名称, + count( score.student_id ) over ( PARTITION BY course.course_id ) 选修人数, + max( score ) over ( PARTITION BY course.course_id ) 最高分, + min( score ) over ( PARTITION BY course.course_id ) 最低分, + avg( score ) over ( PARTITION BY course.course_id ) 平均分, + sum(case when score>=60 then 1 else 0 end) over(partition by course.course_id)/count(*) over(partition by course.course_id) 及格率, + sum(case when score>=70 then 1 else 0 end) over(partition by course.course_id)/count(*) over(partition by course.course_id) 中等率, + sum(case when score>=80 then 1 else 0 end) over(partition by course.course_id)/count(*) over(partition by course.course_id) 优良率, + sum(case when score>=90 then 1 else 0 end) over(partition by course.course_id)/count(*) over(partition by course.course_id) 优秀率 +FROM + score + JOIN course ON score.course_id = course.course_id; + +-- 19. 按各科成绩进行排序，并显示排名，Score 重复时保留名次空缺 + +select student_name,course_id,rank() over(partition by course_id order by score desc) from student join score on student.student_id=score.student_id; + +-- 20. 按各科成绩进行排序，并显示排名，Score 重复时合并名次 + +select student_name,course_id,dense_rank() over(partition by course_id order by score desc) from student join score on student.student_id=score.student_id; + +-- 21. 查询学生的总成绩，并进行排名，总分重复时保留名次空缺 + +SELECT s.student_id,s.student_name, SUM(sc.score) 总成绩,RANK() over(ORDER BY SUM(sc.score) DESC) 排名 from student s JOIN score sc ON s.student_id = sc.student_id GROUP BY sc.student_id; + + +-- 22. 查询学生的总成绩，并进行排名，总分重复时不保留名次空缺 +SELECT s.student_id,s.student_name, SUM(sc.score) 总成绩,DENSE_RANK() over(ORDER BY SUM(sc.score) DESC) 排名 from student s JOIN score sc ON s.student_id = sc.student_id GROUP BY sc.student_id; + +-- 23. 统计各科成绩各分数段人数：课程编号，课程名称，[100-85]，[85-70]，[70-60]，[60-0] 及所占百分比 + +SELECT DISTINCT + course.course_id 课程ID, + course_name 课程名称, + sum(case when score>=85 then 1 else 0 end) over(partition by course.course_id)/count(*) over(partition by course.course_id) `[100-85]占比`, + sum(case when score>=70 then 1 else 0 end) over(partition by course.course_id)/count(*) over(partition by course.course_id) `[85-70]占比`, + sum(case when score>=60 then 1 else 0 end) over(partition by course.course_id)/count(*) over(partition by course.course_id) `[70-60]占比`, + sum(case when score>=0 then 1 else 0 end) over(partition by course.course_id)/count(*) over(partition by course.course_id) `[60-0]占比` +FROM + score + JOIN course ON score.course_id = course.course_id; + +-- !24. 查询各科成绩前三名的记录 + +select student_name,course_name,score,lag(student.student_id,3) over (partition by course.course_id order by score desc )from student join score on student.student_id=score.student_id join course on score.course_id=course.course_id ; + +-- 25. 查询每门课程被选修的学生数 + +select distinct course_id,count(student_id) over(partition by course_id) from score; + +-- 26. 查询出只选修两门课程的学生学号和姓名 + +with a as( +select distinct student.student_id 学生编号,student.student_name 学生姓名,birthday 学生生日,gender 学生性别,count(score.course_id) over(partition by score.student_id) 选课总数,sum(score.score) over(partition by score.student_id) 总成绩 from student left join score on student.student_id=score.student_id left join course on score.course_id=course.course_id) +select 学生编号,学生姓名,选课总数 from a where 选课总数 =2; + +-- 27. 查询男生、女生人数 + +select distinct gender 性别,count(student_name) over(partition by gender) 人数 from student; + +-- 28. 查询名字中含有「风」字的学生信息 + +select * from student where student_name like '%风%'; + +-- 29. 查询同名同性学生名单，并统计同名人数 + + +-- 30. 查询 1990 年出生的学生名单 + +select student_name,year(birthday)from student where year(birthday)=1990; + +-- 31. .查询每门课程的平均成绩，结果按平均成绩降序排列，平均成绩相同时，按课程编号升序排列 +SELECT course_id, AVG(score) 平均成绩 FROM score GROUP BY course_id ORDER BY 平均成绩 DESC, course_id ASC; + +-- 32. .查询平均成绩大于等于 85 的所有学生的学号、姓名和平均成绩 +SELECT sc.student_id, student_name,AVG(score) from score sc INNER JOIN student st on sc.student_id=st.student_id GROUP BY student_id HAVING AVG(score)>=85 + +-- 33.. 查询课程名称为「数学」，且分数低于 60 的学生姓名和分数 +SELECT sc.course_id ,student_name,score from course co INNER JOIN score sc on co.course_id=sc.course_id INNER JOIN student st on sc.student_id=st.student_id where course_name='数学' and score<60; + +-- 34.. 查询所有学生的课程及分数情况（存在学生没成绩，没选课的情况） + +-- 35.. 查询任何一门课程成绩在 70 分以上的姓名、课程名称和分数 + +select student_name,course_name,score from score join student on score.student_id=student.student_id join course on score.course_id=course.course_id where score>70; +-- 36. 查询不及格的课程 + +select student_name,course_name,score from score join student on score.student_id=student.student_id join course on score.course_id=course.course_id where score<60; + +-- 37. .查询课程编号为 1 且课程成绩在 80 分以上的学生的学号和姓名 +SELECT sc.course_id,st.student_name,score from score sc INNER JOIN student st on sc.student_id=st.student_id where sc.course_id=1 and score>80; + +-- 38. .求每门课程的学生人数 +SELECT DISTINCT co.course_id,co.course_name,COUNT(student_id)over(PARTITION by course_name) from course co INNER JOIN score sc on co.course_id=sc.course_id ; + +-- 39. .成绩不重复，查询选修「李白」老师所授课程的学生中，成绩最高的学生信息及其成绩 +-- 40. 成绩有重复的情况下，查询选修「李白」老师所授课程的学生中，成绩最高的学生信息及其成绩 +-- 41. .查询不同课程成绩相同的学生的学生编号、课程编号、学生成绩 +-- 42. .查询每门功成绩最好的前两名 + + +-- 43. .统计每门课程的学生选修人数（超过 5 人的课程才统计）。 +SELECT DISTINCT co.course_id,co.course_name,COUNT(student_id)over(PARTITION by course_name) from course co INNER JOIN score sc on co.course_id=sc.course_id ; + +-- 44. .检索至少选修两门课程的学生学号 +with a as( +select distinct student.student_id 学生编号,count(score.course_id) over(partition by score.student_id) 选课总数,sum(score.score) over(partition by score.student_id) 总成绩 from student left join score on student.student_id=score.student_id left join course on score.course_id=course.course_id) +select 学生编号,选课总数 from a where 选课总数 =2; +-- 45. .查询选修了全部课程的学生信息 +with a as( +select distinct student.student_id 学生编号,student.student_name 学生姓名,birthday 学生生日,gender 学生性别,count(score.course_id) over(partition by score.student_id) 选课总数,sum(score.score) over(partition by score.student_id) 总成绩 from student left join score on student.student_id=score.student_id left join course on score.course_id=course.course_id) +select 学生编号,学生姓名,选课总数 from a where 选课总数 =3; +-- 46. 查询各学生的年龄，只按年份来算 +select student_id,datediff(now(),birthday)/365 年龄 from student; +-- 47. 按照出生日期来算，当前月日 < 出生年月的月日则，年龄减一 + +-- 48. 查询本周过生日的学生 +select * from student where week(birthday)=week(now()); +-- 49. 查询下周过生日的学生 +select * from student where week(birthday)=week(now())+1; +-- 50. 查询本月过生日的学生 +select * from student where month(birthday)=month(now()); +-- 51. 查询下月过生日的学生 +select * from student where month(birthday)=month(now())+1; + + +``` + -- Gitee