mysql练习题二练
题目
查询" 01 "课程比" 02 "课程成绩高的学生的信息及课程分数
查询同时存在" 01 "课程和" 02 "课程的情况
查询存在" 01 "课程但可能不存在" 02 "课程的情况(不存在时显示为 null )
查询不存在" 01 "课程但存在" 02 "课程的情况
查询平均成绩大于等于 60 分的同学的学生编号和学生姓名和平均成绩
查询在 SC 表存在成绩的学生信息 4.1 查有成绩的学生信息
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)
查询「李」姓老师的数量
查询学过「张三」老师授课的同学的信息
查询没有学全所有课程的同学的信息
查询至少有一门课与学号为" 01 "的同学所学相同的同学的信息
查询和" 01 "号的同学学习的课程 完全相同的其他同学的信息 group_concat函数的使用
查询没学过"张三"老师讲授的任一门课程的学生姓名
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
检索" 01 "课程分数小于 60，按分数降序排列的学生信息
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
查询各科成绩最高分、最低分和平均分： 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
按各科成绩进行排序，并显示排名， Score 重复时保留名次空缺
-- 这里不知道咋在cid发生改变的时候将rank也重新计算了。。
-- 搞不出来
15.1 按各科成绩进行排序，并显示排名， Score 重复时合并名次
查询学生的总成绩，并进行排名，总分重复时保留名次空缺
16.1 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
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
查询各科成绩前三名的记录
查询每门课程被选修的学生数
查询出只选修两门课程的学生学号和姓名
查询男生、女生人数
查询名字中含有「风」字的学生信息
查询同名同性学生名单，并统计同名人数
查询 1990 年出生的学生名单
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
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
查询课程名称为「数学」，且分数低于 60 的学生姓名和分数
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）
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
查询不及格的课程
查询课程编号为 01 且课程成绩在 80 分以上的学生的学号和姓名
求每门课程的学生人数
成绩不重复，查询选修「张三」老师所授课程的学生中，成绩最高的学生信息及其成绩
成绩有重复的情况下，查询选修「张三」老师所授课程的学生中，成绩最高的学生信息及其成绩
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
查询每门功成绩最好的前两名
统计每门课程的学生选修人数（超过 5 人的课程才统计）。
检索至少选修两门课程的学生学号
查询选修了全部课程的学生信息
查询各学生的年龄，只按年份来算
按照出生日期来算，当前月日 < 出生年月的月日则，年龄减一
查询本周过生日的学生
查询下周过生日的学生
查询本月过生日的学生
查询下月过生日的学生
查询" 01 "课程比" 02 "课程成绩高的学生的信息及课程分数
select s.*,s1.cid,s1.score,s2.cid,s2.score from student s join (select sid,cid,score from sc where cid = 01) s1 join (select sid,cid,score from sc where cid = 02) s2
on s1.sid=s2.sid and s1.score > s2.score and s.sid=s1.sid;
查询同时存在" 01 "课程和" 02 "课程的情况
select * from (select * from sc where cid=01) s1 join (select * from sc where cid=02) s2 on s1.sid=s2.sid;
查询存在" 01 "课程但可能不存在" 02 "课程的情况(不存在时显示为 null )
select * from (select * from sc where cid=01) s1 left join (select * from sc where cid=02) s2 on s1.sid=s2.sid;
查询不存在" 01 "课程但存在" 02 "课程的情况
select * from sc where sid not in (select sid from sc where cid=01) and cid = 02;
查询平均成绩大于等于 60 分的同学的学生编号和学生姓名和平均成绩
select s.sid,s.sname,avg(sc.score) from student s join sc where s.sid=sc.sid group by sc.sid having avg(sc.score)>60;
查询在 SC 表存在成绩的学生信息 4.1 查有成绩的学生信息
select distinct s.* from student s join sc where s.sid=sc.sid;
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 s.sid,s.sname,c.cidSum as '选课总数',c.scoreSum as '总成绩' from student s left join
(select sid,count(cid) as cidSum,sum(score) as scoreSum from sc group by sid) c on s.SId=c.sid;
查询「李」姓老师的数量
select count(*) from teacher where tname like "李%";
查询学过「张三」老师授课的同学的信息
select s.* from student s join sc on sc.cid = (select c.cid kcid from teacher t join course c on t.tname="张三" and t.tid=c.tid)
and s.sid=sc.sid;
查询没有学全所有课程的同学的信息
select s.* from student s left join sc on s.sid=sc.sid group by s.sid having count(sc.cid)<(select count(cid) from course);
查询至少有一门课与学号为" 01 "的同学所学相同的同学的信息
select * from student where sid in (select sid from sc where cid in (select cid from sc where sid=01)) group by sid;
查询和" 01 "号的同学学习的课程 完全相同的其他同学的信息 group_concat函数的使用
select * from student
where sid in
(select sid from sc
where sid != 1
group by sid
having group_concat(cid ORDER BY cid ) =
(select group_concat(cid ORDER BY cid )from sc where sid =01))
查询没学过"张三"老师讲授的任一门课程的学生姓名
select distinct sid,sname from student where sid not in
(select sc.sid from course c join teacher t join sc on tname="张三" and t.tid=c.tid and sc.cid=c.cid);
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 s1.sid,s1.sname,s2.a from student s1 join (select sid,count(cid) c,avg(score) a from sc where score<60 group by sid) s2
on s1.sid=s2.sid and s2.c>=2;
检索" 01 "课程分数小于 60，按分数降序排列的学生信息
select DISTINCT s.* from student s join sc on sc.cid=01 and sc.score<60 and s.sid=sc.sid order by sc.score desc
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 sid,cid,sum(score) 总成绩,avg(score) 平均成绩 from sc group by sid order by avg(score) desc;
查询各科成绩最高分、最低分和平均分： 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 c.cid,c.cname,count(sc.sid) '选修人数',max(sc.score) '最高分',min(sc.score) '最低分',
CONCAT(count(case when score>=70 and score<80 then 'zd' END)/count(sc.sid)*100,'%') '中等率',
CONCAT(count(case when score>=80 and score<90 then 'yl' END)/count(sc.sid)*100,'%') '优良率',
CONCAT(count(case when score>=90 then 'yx' END)/count(sc.sid)*100,'%') '优秀率',
CONCAT(count(case when score>=60 then 'jg' END)/count(sc.sid)*100,'%') '及格率'
from course c join sc on c.cid=sc.cid group by sc.cid
按各科成绩进行排序，并显示排名， Score 重复时保留名次空缺
-- 这里不知道咋在cid发生改变的时候将rank也重新计算了。。
select cid,score,@rank:=@rank+1 rank from sc join (select @rank:=0) rank order by cid asc,score desc；
-- 搞不出来
select * from (select cid,score,@rank1:=@rank1+1 rank1 from sc join (select @rank1:=0) rank1 on cid=01 order by score desc) a
join (select cid,score,@rank2:=@rank2+1 rank2 from sc join (select @rank2:=0) rank2 on cid=02 order by score desc) b
join (select cid,score,@rank3:=@rank3+1 rank3 from sc join (select @rank3:=0) rank3 on cid=03 order by score desc) c
15.1 按各科成绩进行排序，并显示排名， Score 重复时合并名次
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 a.*,@rank:=@rank+1 '排名' from
(select sc.sid,sum(sc.score) '总成绩' from sc group by sc.sid ORDER BY sum(sc.score) desc) a
join (select @rank:=0) rank
16.1 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
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
case when score<=100 and score>85 then '' end
select cid,CONCAT(count(case when score<=100 and score>85 then '' end)/count(sc.sid)*100,'%') '[100-85]占比',
查询各科成绩前三名的记录
sele
查询每门课程被选修的学生数
select cid,count(sid) from sc group by cid;
查询出只选修两门课程的学生学号和姓名
select s.sid,s.sname from student s join sc on sc.sid=s.sid group by sc.sid having count(sc.cid)=2
查询男生、女生人数
select ssex,count(sid) from student group by ssex;
查询名字中含有「风」字的学生信息
select * from student where sname like '%风%'
查询同名同性学生名单，并统计同名人数
select s1.*,(@num:=2) '人数' from student s1 join student s2 join (select @num:=0) a on s1.sname=s2.sname and s1.ssex=s2.ssex and s1.sid!=s2.sid;
查询 1990 年出生的学生名单
select * from student where YEAR(Sage)=1990;
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 cid,avg(score) '平均成绩' from sc group by cid order by avg(score) desc,cid asc;
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 s.sid,s.sname,avg(sc.score) from student s join sc group by sc.sid having avg(sc.score)>85;
查询课程名称为「数学」，且分数低于 60 的学生姓名和分数
select s1.sid,s1.sname,s2.score from student s1 join sc s2 on s2.cid=(select cid from course where cname='数学') and s1.sid=s2.sid;
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）
select s.sid,sc.cid,sc.score from student s left join sc on sc.sid=s.sid;
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 s.sname '学生姓名',c.mz '课程名字',c.fs '分数' from student s join
(select sc.sid xh,c1.cname mz,sc.score fs from course c1 join sc on c1.cid=sc.cid and sc.score>70) c on c.xh=s.sid;
select s.sname '学生姓名',c.mz '课程名字',c.fs '分数' from student s where s.sid not in (select distinct sid from sc where score<70);
select s.sname '学生姓名',c.mz '课程名字',c.fs '分数' from student s join sc s1 on s.sid=s1.sid group by s1.sid having s1.score<70;
查询不及格的课程
select cid,score from sc where score<60;
查询课程编号为 01 且课程成绩在 80 分以上的学生的学号和姓名
select s.sid,s.sname from student s join sc on sc.cid=01 and sc.score>80 and sc.sid=s.sid;
求每门课程的学生人数
select cid,count(sid) from sc group by cid;
成绩不重复，查询选修「张三」老师所授课程的学生中，成绩最高的学生信息及其成绩
select s1.*,s2.score from student s1 join
(select cid,sid,score from sc where cid=(select cid from course c join teacher t on t.tname='张三' and c.tid=t.tid) having max(score)) s2 on s2.sid=s1.sid;
成绩有重复的情况下，查询选修「张三」老师所授课程的学生中，成绩最高的学生信息及其成绩
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
select s.sid,sc.cid,sc.score from student s join (select sid,cid,score from sc where)
查询每门功成绩最好的前两名
(select sid,cid,score from sc where cid=01 order by score desc limit 2)
union
(select sid,cid,score from sc where cid=02 order by score desc limit 2)
union
(select sid,cid,score from sc where cid=03 order by score desc limit 2)
统计每门课程的学生选修人数（超过 5 人的课程才统计）。
select cid,count(sid) from sc group by cid having count(sid)>5;
检索至少选修两门课程的学生学号
select sid from sc group by sid having count(cid)>=2;
查询选修了全部课程的学生信息
SELECT s.* from student s join sc on s.sid=sc.sid group by sc.sid having count(sc.cid)=(select count(*) from course);
查询各学生的年龄，只按年份来算
select sname '姓名',(YEAR(CURRENT_DATE)-year(sage)) 年龄 from student;
按照出生日期来算，当前月日 < 出生年月的月日则，年龄减一
select sname '姓名',(YEAR(CURRENT_DATE)-year(sage)) 年龄 from student;
查询本周过生日的学生
select * from student where week(CONCAT(YEAR(CURRENT_DATE),mid(sage,5,6)))=week(CURRENT_DATE);
查询下周过生日的学生
select * from student where week(CONCAT(YEAR(CURRENT_DATE),mid(sage,5,6)))=week(CURRENT_DATE)+1;
查询本月过生日的学生
select * from student where MONTH(sage)=MONTH(CURRENT_DATE);
查询下月过生日的学生
select * from student where MONTH(sage)=MONTH(CURRENT_DATE)+1;
结合项目中 做报表的时候查询指定时间内的数据
switch(dateRange) {
case "今日":
sql += " DATE_FORMAT(?,'%m-%d') = DATE_FORMAT(NOW(), '%m-%d')";
break;
case "本周":
sql += " week(CONCAT(YEAR(CURRENT_DATE),mid(?,5,6)))=week(CURRENT_DATE)";
break;
case "本月":
sql += " MONTH(?)=MONTH(CURRENT_DATE)";
break;
case "全年":
sql += " YEAR(?)=YEAR(CURRENT_DATE)";
break;
// default:
// System.out.println("default");
}
表结构内容
/*
Navicat Premium Data Transfer
Source Server : mm
Source Server Type : MySQL
Source Server Version : 50640
Source Host : localhost:3306
Source Schema : practice1
Target Server Type : MySQL
Target Server Version : 50640
File Encoding : 65001
Date: 14/04/2025 14:47:05
*/
SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;
-- ----------------------------
-- Table structure for course
-- ----------------------------
DROP TABLE IF EXISTS `course`;
CREATE TABLE `course` (
`CId` varchar(10) CHARACTER SET latin1 COLLATE latin1_swedish_ci DEFAULT NULL,
`Cname` varchar(10) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`TId` varchar(10) CHARACTER SET latin1 COLLATE latin1_swedish_ci DEFAULT NULL
) ENGINE = InnoDB CHARACTER SET = latin1 COLLATE = latin1_swedish_ci ROW_FORMAT = Compact;
-- ----------------------------
-- Records of course
-- ----------------------------
INSERT INTO `course` VALUES ('01', '语文', '02');
INSERT INTO `course` VALUES ('02', '数学', '01');
INSERT INTO `course` VALUES ('03', '英语', '03');
-- ----------------------------
-- Table structure for sc
-- ----------------------------
DROP TABLE IF EXISTS `sc`;
CREATE TABLE `sc` (
`SId` varchar(10) CHARACTER SET latin1 COLLATE latin1_swedish_ci DEFAULT NULL,
`CId` varchar(10) CHARACTER SET latin1 COLLATE latin1_swedish_ci DEFAULT NULL,
`score` decimal(18, 1) DEFAULT NULL,
INDEX `SC_CID`(`CId`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = latin1 COLLATE = latin1_swedish_ci ROW_FORMAT = Compact;
-- ----------------------------
-- Records of sc
-- ----------------------------
INSERT INTO `sc` VALUES ('01', '01', 80.0);
INSERT INTO `sc` VALUES ('01', '02', 90.0);
INSERT INTO `sc` VALUES ('01', '03', 99.0);
INSERT INTO `sc` VALUES ('02', '01', 70.0);
INSERT INTO `sc` VALUES ('02', '02', 60.0);
INSERT INTO `sc` VALUES ('02', '03', 80.0);
INSERT INTO `sc` VALUES ('03', '01', 80.0);
INSERT INTO `sc` VALUES ('03', '02', 80.0);
INSERT INTO `sc` VALUES ('03', '03', 80.0);
INSERT INTO `sc` VALUES ('04', '01', 50.0);
INSERT INTO `sc` VALUES ('04', '02', 30.0);
INSERT INTO `sc` VALUES ('04', '03', 20.0);
INSERT INTO `sc` VALUES ('05', '01', 76.0);
INSERT INTO `sc` VALUES ('05', '02', 87.0);
INSERT INTO `sc` VALUES ('06', '01', 31.0);
INSERT INTO `sc` VALUES ('06', '03', 34.0);
INSERT INTO `sc` VALUES ('07', '02', 89.0);
INSERT INTO `sc` VALUES ('07', '03', 98.0);
-- ----------------------------
-- Table structure for student
-- ----------------------------
DROP TABLE IF EXISTS `student`;
CREATE TABLE `student` (
`SId` varchar(10) CHARACTER SET latin1 COLLATE latin1_swedish_ci DEFAULT NULL,
`Sname` varchar(10) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL,
`Sage` datetime(0) DEFAULT NULL,
`Ssex` varchar(10) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL
) ENGINE = InnoDB CHARACTER SET = latin1 COLLATE = latin1_swedish_ci ROW_FORMAT = Compact;
-- ----------------------------
-- Records of student
-- ----------------------------
INSERT INTO `student` VALUES ('01', '赵雷', '1990-01-01 00:00:00', '男');
INSERT INTO `student` VALUES ('02', '钱电', '1990-12-21 00:00:00', '男');
INSERT INTO `student` VALUES ('03', '孙风', '1990-05-20 00:00:00', '男');
INSERT INTO `student` VALUES ('04', '李云', '1990-08-06 00:00:00', '男');
INSERT INTO `student` VALUES ('05', '周梅', '1991-12-01 00:00:00', '女');
INSERT INTO `student` VALUES ('06', '吴兰', '1992-03-01 00:00:00', '女');
INSERT INTO `student` VALUES ('07', '郑竹', '1989-07-01 00:00:00', '女');
INSERT INTO `student` VALUES ('09', '张三', '2017-12-20 00:00:00', '女');
INSERT INTO `student` VALUES ('10', '李四', '2017-12-25 00:00:00', '女');
INSERT INTO `student` VALUES ('11', '李四', '2017-12-30 00:00:00', '女');
INSERT INTO `student` VALUES ('12', '赵六', '2017-01-01 00:00:00', '女');
INSERT INTO `student` VALUES ('13', '孙七', '2018-01-01 00:00:00', '女');
-- ----------------------------
-- Table structure for teacher
-- ----------------------------
DROP TABLE IF EXISTS `teacher`;
CREATE TABLE `teacher` (
`TId` varchar(10) CHARACTER SET latin1 COLLATE latin1_swedish_ci DEFAULT NULL,
`Tname` varchar(10) CHARACTER SET utf8 COLLATE utf8_general_ci DEFAULT NULL
) ENGINE = InnoDB CHARACTER SET = latin1 COLLATE = latin1_swedish_ci ROW_FORMAT = Compact;
-- ----------------------------
-- Records of teacher
-- ----------------------------
INSERT INTO `teacher` VALUES ('01', '张三');
INSERT INTO `teacher` VALUES ('02', '李四');
INSERT INTO `teacher` VALUES ('03', '王五');
SET FOREIGN_KEY_CHECKS = 1;
# 学生表
create table Student(
SId varchar(10),
Sname varchar(10),
Sage datetime,
Ssex varchar(10)
);
# 教师表
create table Teacher(
TId varchar(10),
Tname varchar(10)
);
# 科目表
create table Course(
CID varchar(10),
Cname nvarchar(10),
TId varchar(10)
);
# 成绩表
create table SC(
SId varchar(10),
CID varchar(10),
score decimal(18,1)
);
#学生表
insert into Student values('01','赵雷','1990-01-01','男');
insert into Student values('02','钱电','1990-12-21','男');
insert into Student values('03','孙风','1990-05-20','男');
insert into Student values('04' ,'李云','1990-08-06','男');
insert into Student values('05','周梅','1991-12-01','女');
insert into Student values('06','吴兰','1992-03-01','女');
insert into Student values('07','郑竹','1999-07-01','女');
insert into Student values('09','张三','2017-12-20','女');
insert into Student values('10','李四','2017-12-25','女');
insert into Student values('11','李四','2017-12-30','女');
insert into Student values('12','赵六','2017-01-01','女');
insert into Student values('13','孙七','2018-01-01','女');
#科目表Course
insert into Course values('01','语文','02');
insert into Course values('02','数学','01');
insert into Course values('03','英语','03');
#教师表
insert into Teacher values('01','张三');
insert into Teacher values('02','李四');
insert into Teacher values('03','王五');
#成绩表
insert into SC(CId,score,SId) values('01',110.5,'01');
insert into SC(CId,score,SId) values('02',33.5,'01');
insert into SC(CId,score,SId) values('03',90.2,'01');
insert into SC(CId,score,SId) values('01',79,'02');
insert into SC(CId,score,SId) values('02',19,'02');
insert into SC(CId,score,SId) values('03',59,'02');
insert into SC(CId,score,SId) values('01',120,'03');
insert into SC(CId,score,SId) values('02',110,'03');
insert into SC(CId,score,SId) values('03',100,'03');
本文来自博客园，作者：没有烦恼的猫猫，转载请注明原文链接：https://www.cnblogs.com/maomao777/p/16016543.html
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