MySQL測試題
一、表關系
請創建如下表,並創建相關約束
二、操作表
1、自行創建測試數據
2、查詢“生物”課程比“物理”課程成績高的所有學生的學號;
3、查詢平均成績大於60分的同學的學號和平均成績;
4、查詢所有同學的學號、姓名、選課數、總成績;
5、查詢姓“李”的老師的個數;
6、查詢沒學過“葉平”老師課的同學的學號、姓名;
7、查詢學過“001”並且也學過編號“002”課程的同學的學號、姓名;
8、查詢學過“葉平”老師所教的所有課的同學的學號、姓名;
9、查詢課程編號“002”的成績比課程編號“001”課程低的所有同學的學號、姓名;
10、查詢有課程成績小於60分的同學的學號、姓名;
11、查詢沒有學全所有課的同學的學號、姓名;
12、查詢至少有一門課與學號為“001”的同學所學相同的同學的學號和姓名;
13、查詢至少學過學號為“001”同學所選課程中任意一門課的其他同學學號和姓名;
14、查詢和“002”號的同學學習的課程完全相同的其他同學學號和姓名;
15、刪除學習“葉平”老師課的SC表記錄;
16、向SC表中插入一些記錄,這些記錄要求符合以下條件:①沒有上過編號“002”課程的同學學號;②插入“002”號課程的平均成績;
17、按平均成績從低到高顯示所有學生的“語文”、“數學”、“英語”三門的課程成績,按如下形式顯示: 學生ID,語文,數學,英語,有效課程數,有效平均分;
18、查詢各科成績最高和最低的分:以如下形式顯示:課程ID,最高分,最低分;
19、按各科平均成績從低到高和及格率的百分數從高到低順序;
20、課程平均分從高到低顯示(現實任課老師);
21、查詢各科成績前三名的記錄:(不考慮成績並列情況)
22、查詢每門課程被選修的學生數;
23、查詢出只選修了一門課程的全部學生的學號和姓名;
24、查詢男生、女生的人數;
25、查詢姓“張”的學生名單;
26、查詢同名同姓學生名單,並統計同名人數;
27、查詢每門課程的平均成績,結果按平均成績升序排列,平均成績相同時,按課程號降序排列;
28、查詢平均成績大於85的所有學生的學號、姓名和平均成績;
29、查詢課程名稱為“數學”,且分數低於60的學生姓名和分數;
30、查詢課程編號為003且課程成績在80分以上的學生的學號和姓名;
31、求選了課程的學生人數
32、查詢選修“楊艷”老師所授課程的學生中,成績最高的學生姓名及其成績;
33、查詢各個課程及相應的選修人數;
34、查詢不同課程但成績相同的學生的學號、課程號、學生成績;
35、查詢每門課程成績最好的前兩名;
36、檢索至少選修兩門課程的學生學號;
37、查詢全部學生都選修的課程的課程號和課程名;
38、查詢沒學過“葉平”老師講授的任一門課程的學生姓名;
39、查詢兩門以上不及格課程的同學的學號及其平均成績;
40、檢索“004”課程分數小於60,按分數降序排列的同學學號;
41、刪除“002”同學的“001”課程的成績;
導出現有數據庫數據:
- mysqldump -u用戶名 -p密碼 數據庫名稱 >導出文件路徑 # 結構+數據
- mysqldump -u用戶名 -p密碼 -d 數據庫名稱 >導出文件路徑 # 結構
導入現有數據庫數據:
- mysqldump -uroot -p密碼 數據庫名稱 < 文件路徑

Navicat Premium Data Transfer Source Server : localhost Source Server Type : MySQL Source Server Version : 50624 Source Host : localhost Source Database : sqlexam Target Server Type : MySQL Target Server Version : 50624 File Encoding : utf-8 Date: 10/21/2016 06:46:46 AM */ SET NAMES utf8; SET FOREIGN_KEY_CHECKS = 0; -- ---------------------------- -- Table structure for `class` -- ---------------------------- DROP TABLE IF EXISTS `class`; CREATE TABLE `class` ( `cid` int(11) NOT NULL AUTO_INCREMENT, `caption` varchar(32) NOT NULL, PRIMARY KEY (`cid`) ) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8; -- ---------------------------- -- Records of `class` -- ---------------------------- BEGIN; INSERT INTO `class` VALUES ('1', '三年二班'), ('2', '三年三班'), ('3', '一年二班'), ('4', '二年九班'); COMMIT; -- ---------------------------- -- Table structure for `course` -- ---------------------------- DROP TABLE IF EXISTS `course`; CREATE TABLE `course` ( `cid` int(11) NOT NULL AUTO_INCREMENT, `cname` varchar(32) NOT NULL, `teacher_id` int(11) NOT NULL, PRIMARY KEY (`cid`), KEY `fk_course_teacher` (`teacher_id`), CONSTRAINT `fk_course_teacher` FOREIGN KEY (`teacher_id`) REFERENCES `teacher` (`tid`) ) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8; -- ---------------------------- -- Records of `course` -- ---------------------------- BEGIN; INSERT INTO `course` VALUES ('1', '生物', '1'), ('2', '物理', '2'), ('3', '體育', '3'), ('4', '美術', '2'); COMMIT; -- ---------------------------- -- Table structure for `score` -- ---------------------------- DROP TABLE IF EXISTS `score`; CREATE TABLE `score` ( `sid` int(11) NOT NULL AUTO_INCREMENT, `student_id` int(11) NOT NULL, `course_id` int(11) NOT NULL, `num` int(11) NOT NULL, PRIMARY KEY (`sid`), KEY `fk_score_student` (`student_id`), KEY `fk_score_course` (`course_id`), CONSTRAINT `fk_score_course` FOREIGN KEY (`course_id`) REFERENCES `course` (`cid`), CONSTRAINT `fk_score_student` FOREIGN KEY (`student_id`) REFERENCES `student` (`sid`) ) ENGINE=InnoDB AUTO_INCREMENT=53 DEFAULT CHARSET=utf8; -- ---------------------------- -- Records of `score` -- ---------------------------- BEGIN; INSERT INTO `score` VALUES ('1', '1', '1', '10'), ('2', '1', '2', '9'), ('5', '1', '4', '66'), ('6', '2', '1', '8'), ('8', '2', '3', '68'), ('9', '2', '4', '99'), ('10', '3', '1', '77'), ('11', '3', '2', '66'), ('12', '3', '3', '87'), ('13', '3', '4', '99'), ('14', '4', '1', '79'), ('15', '4', '2', '11'), ('16', '4', '3', '67'), ('17', '4', '4', '100'), ('18', '5', '1', '79'), ('19', '5', '2', '11'), ('20', '5', '3', '67'), ('21', '5', '4', '100'), ('22', '6', '1', '9'), ('23', '6', '2', '100'), ('24', '6', '3', '67'), ('25', '6', '4', '100'), ('26', '7', '1', '9'), ('27', '7', '2', '100'), ('28', '7', '3', '67'), ('29', '7', '4', '88'), ('30', '8', '1', '9'), ('31', '8', '2', '100'), ('32', '8', '3', '67'), ('33', '8', '4', '88'), ('34', '9', '1', '91'), ('35', '9', '2', '88'), ('36', '9', '3', '67'), ('37', '9', '4', '22'), ('38', '10', '1', '90'), ('39', '10', '2', '77'), ('40', '10', '3', '43'), ('41', '10', '4', '87'), ('42', '11', '1', '90'), ('43', '11', '2', '77'), ('44', '11', '3', '43'), ('45', '11', '4', '87'), ('46', '12', '1', '90'), ('47', '12', '2', '77'), ('48', '12', '3', '43'), ('49', '12', '4', '87'), ('52', '13', '3', '87'); COMMIT; -- ---------------------------- -- Table structure for `student` -- ---------------------------- DROP TABLE IF EXISTS `student`; CREATE TABLE `student` ( `sid` int(11) NOT NULL AUTO_INCREMENT, `gender` char(1) NOT NULL, `class_id` int(11) NOT NULL, `sname` varchar(32) NOT NULL, PRIMARY KEY (`sid`), KEY `fk_class` (`class_id`), CONSTRAINT `fk_class` FOREIGN KEY (`class_id`) REFERENCES `class` (`cid`) ) ENGINE=InnoDB AUTO_INCREMENT=17 DEFAULT CHARSET=utf8; -- ---------------------------- -- Records of `student` -- ---------------------------- BEGIN; INSERT INTO `student` VALUES ('1', '男', '1', '理解'), ('2', '女', '1', '鋼蛋'), ('3', '男', '1', '張三'), ('4', '男', '1', '張一'), ('5', '女', '1', '張二'), ('6', '男', '1', '張四'), ('7', '女', '2', '鐵錘'), ('8', '男', '2', '李三'), ('9', '男', '2', '李一'), ('10', '女', '2', '李二'), ('11', '男', '2', '李四'), ('12', '女', '3', '如花'), ('13', '男', '3', '劉三'), ('14', '男', '3', '劉一'), ('15', '女', '3', '劉二'), ('16', '男', '3', '劉四'); COMMIT; -- ---------------------------- -- Table structure for `teacher` -- ---------------------------- DROP TABLE IF EXISTS `teacher`; CREATE TABLE `teacher` ( `tid` int(11) NOT NULL AUTO_INCREMENT, `tname` varchar(32) NOT NULL, PRIMARY KEY (`tid`) ) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8; -- ---------------------------- -- Records of `teacher` -- ---------------------------- BEGIN; INSERT INTO `teacher` VALUES ('1', '張磊老師'), ('2', '李平老師'), ('3', '劉海燕老師'), ('4', '朱雲海老師'), ('5', '李傑老師'); COMMIT; SET FOREIGN_KEY_CHECKS = 1;
1 2、查詢“生物”課程比“物理”課程成績高的所有學生的學號; 2 思路: 3 獲取所有有生物課程的人(學號,成績) - 臨時表 4 獲取所有有物理課程的人(學號,成績) - 臨時表 5 根據【學號】連接兩個臨時表: 6 學號 物理成績 生物成績 7 8 然后再進行篩選 9 10 select A.student_id,sw,ty from 11 12 (select student_id,num as sw from score left join course on score.course_id = course.cid where course.cname = '生物') as A 13 14 left join 15 16 (select student_id,num as ty from score left join course on score.course_id = course.cid where course.cname = '體育') as B 17 18 on A.student_id = B.student_id where sw > if(isnull(ty),0,ty); 19 20 3、查詢平均成績大於60分的同學的學號和平均成績; 21 思路: 22 根據學生分組,使用avg獲取平均值,通過having對avg進行篩選 23 24 select student_id,avg(num) from score group by student_id having avg(num) > 60 25 26 4、查詢所有同學的學號、姓名、選課數、總成績; 27 28 select score.student_id,sum(score.num),count(score.student_id),student.sname 29 from 30 score left join student on score.student_id = student.sid 31 group by score.student_id 32 33 5、查詢姓“李”的老師的個數; 34 select count(tid) from teacher where tname like '李%' 35 36 select count(1) from (select tid from teacher where tname like '李%') as B 37 38 6、查詢沒學過“葉平”老師課的同學的學號、姓名; 39 思路: 40 先查到“李平老師”老師教的所有課ID 41 獲取選過課的所有學生ID 42 學生表中篩選 43 select * from student where sid not in ( 44 select DISTINCT student_id from score where score.course_id in ( 45 select cid from course left join teacher on course.teacher_id = teacher.tid where tname = '李平老師' 46 ) 47 ) 48 49 7、查詢學過“001”並且也學過編號“002”課程的同學的學號、姓名; 50 思路: 51 先查到既選擇001又選擇002課程的所有同學 52 根據學生進行分組,如果學生數量等於2表示,兩門均已選擇 53 54 select student_id,sname from 55 56 (select student_id,course_id from score where course_id = 1 or course_id = 2) as B 57 58 left join student on B.student_id = student.sid group by student_id HAVING count(student_id) > 1 59 60 61 8、查詢學過“葉平”老師所教的所有課的同學的學號、姓名; 62 63 同上,只不過將001和002變成 in (葉平老師的所有課) 64 65 9、查詢課程編號“002”的成績比課程編號“001”課程低的所有同學的學號、姓名; 66 同第1題 67 68 69 10、查詢有課程成績小於60分的同學的學號、姓名; 70 71 select sid,sname from student where sid in ( 72 select distinct student_id from score where num < 60 73 ) 74 75 11、查詢沒有學全所有課的同學的學號、姓名; 76 思路: 77 在分數表中根據學生進行分組,獲取每一個學生選課數量 78 如果數量 == 總課程數量,表示已經選擇了所有課程 79 80 select student_id,sname 81 from score left join student on score.student_id = student.sid 82 group by student_id HAVING count(course_id) = (select count(1) from course) 83 84 85 12、查詢至少有一門課與學號為“001”的同學所學相同的同學的學號和姓名; 86 思路: 87 獲取 001 同學選擇的所有課程 88 獲取課程在其中的所有人以及所有課程 89 根據學生篩選,獲取所有學生信息 90 再與學生表連接,獲取姓名 91 92 select student_id,sname, count(course_id) 93 from score left join student on score.student_id = student.sid 94 where student_id != 1 and course_id in (select course_id from score where student_id = 1) group by student_id 95 96 13、查詢至少學過學號為“001”同學所有課的其他同學學號和姓名; 97 先找到和001的學過的所有人 98 然后個數 = 001所有學科 ==》 其他人可能選擇的更多 99 100 select student_id,sname, count(course_id) 101 from score left join student on score.student_id = student.sid 102 where student_id != 1 and course_id in (select course_id from score where student_id = 1) group by student_id having count(course_id) = (select count(course_id) from score where student_id = 1) 103 104 14、查詢和“002”號的同學學習的課程完全相同的其他同學學號和姓名; 105 106 個數相同 107 002學過的也學過 108 109 select student_id,sname from score left join student on score.student_id = student.sid where student_id in ( 110 select student_id from score where student_id != 1 group by student_id HAVING count(course_id) = (select count(1) from score where student_id = 1) 111 ) and course_id in (select course_id from score where student_id = 1) group by student_id HAVING count(course_id) = (select count(1) from score where student_id = 1) 112 113 114 15、刪除學習“葉平”老師課的score表記錄; 115 116 delete from score where course_id in ( 117 select cid from course left join teacher on course.teacher_id = teacher.tid where teacher.name = '葉平' 118 ) 119 120 16、向SC表中插入一些記錄,這些記錄要求符合以下條件:①沒有上過編號“002”課程的同學學號;②插入“002”號課程的平均成績; 121 思路: 122 由於insert 支持 123 inset into tb1(xx,xx) select x1,x2 from tb2; 124 所有,獲取所有沒上過002課的所有人,獲取002的平均成績 125 126 insert into score(student_id, course_id, num) select sid,2,(select avg(num) from score where course_id = 2) 127 from student where sid not in ( 128 select student_id from score where course_id = 2 129 ) 130 131 17、按平均成績從低到高 顯示所有學生的“語文”、“數學”、“英語”三門的課程成績,按如下形式顯示: 學生ID,語文,數學,英語,有效課程數,有效平均分; 132 select sc.student_id, 133 (select num from score left join course on score.course_id = course.cid where course.cname = "生物" and score.student_id=sc.student_id) as sy, 134 (select num from score left join course on score.course_id = course.cid where course.cname = "物理" and score.student_id=sc.student_id) as wl, 135 (select num from score left join course on score.course_id = course.cid where course.cname = "體育" and score.student_id=sc.student_id) as ty, 136 count(sc.course_id), 137 avg(sc.num) 138 from score as sc 139 group by student_id desc 140 141 18、查詢各科成績最高和最低的分:以如下形式顯示:課程ID,最高分,最低分; 142 143 select course_id, max(num) as max_num, min(num) as min_num from score group by course_id; 144 145 19、按各科平均成績從低到高和及格率的百分數從高到低順序; 146 思路:case when .. then 147 select course_id, avg(num) as avgnum,sum(case when score.num > 60 then 1 else 0 END)/count(1)*100 as percent from score group by course_id order by avgnum asc,percent desc; 148 149 20、課程平均分從高到低顯示(現實任課老師); 150 151 select avg(if(isnull(score.num),0,score.num)),teacher.tname from course 152 left join score on course.cid = score.course_id 153 left join teacher on course.teacher_id = teacher.tid 154 155 group by score.course_id 156 157 158 21、查詢各科成績前三名的記錄:(不考慮成績並列情況) 159 select score.sid,score.course_id,score.num,T.first_num,T.second_num from score left join 160 ( 161 select 162 sid, 163 (select num from score as s2 where s2.course_id = s1.course_id order by num desc limit 0,1) as first_num, 164 (select num from score as s2 where s2.course_id = s1.course_id order by num desc limit 3,1) as second_num 165 from 166 score as s1 167 ) as T 168 on score.sid =T.sid 169 where score.num <= T.first_num and score.num >= T.second_num 170 171 22、查詢每門課程被選修的學生數; 172 173 select course_id, count(1) from score group by course_id; 174 175 23、查詢出只選修了一門課程的全部學生的學號和姓名; 176 select student.sid, student.sname, count(1) from score 177 178 left join student on score.student_id = student.sid 179 180 group by course_id having count(1) = 1 181 182 183 24、查詢男生、女生的人數; 184 select * from 185 (select count(1) as man from student where gender='男') as A , 186 (select count(1) as feman from student where gender='女') as B 187 188 25、查詢姓“張”的學生名單; 189 select sname from student where sname like '張%'; 190 191 26、查詢同名同姓學生名單,並統計同名人數; 192 193 select sname,count(1) as count from student group by sname; 194 195 27、查詢每門課程的平均成績,結果按平均成績升序排列,平均成績相同時,按課程號降序排列; 196 select course_id,avg(if(isnull(num), 0 ,num)) as avg from score group by course_id order by avg asc,course_id desc; 197 198 28、查詢平均成績大於85的所有學生的學號、姓名和平均成績; 199 200 select student_id,sname, avg(if(isnull(num), 0 ,num)) from score left join student on score.student_id = student.sid group by student_id; 201 202 29、查詢課程名稱為“數學”,且分數低於60的學生姓名和分數; 203 204 select student.sname,score.num from score 205 left join course on score.course_id = course.cid 206 left join student on score.student_id = student.sid 207 where score.num < 60 and course.cname = '生物' 208 209 30、查詢課程編號為003且課程成績在80分以上的學生的學號和姓名; 210 select * from score where score.student_id = 3 and score.num > 80 211 212 31、求選了課程的學生人數 213 214 select count(distinct student_id) from score 215 216 select count(c) from ( 217 select count(student_id) as c from score group by student_id) as A 218 219 32、查詢選修“楊艷”老師所授課程的學生中,成績最高的學生姓名及其成績; 220 221 select sname,num from score 222 left join student on score.student_id = student.sid 223 where score.course_id in (select course.cid from course left join teacher on course.teacher_id = teacher.tid where tname='張磊老師') order by num desc limit 1; 224 225 33、查詢各個課程及相應的選修人數; 226 select course.cname,count(1) from score 227 left join course on score.course_id = course.cid 228 group by course_id; 229 230 231 34、查詢不同課程但成績相同的學生的學號、課程號、學生成績; 232 select DISTINCT s1.course_id,s2.course_id,s1.num,s2.num from score as s1, score as s2 where s1.num = s2.num and s1.course_id != s2.course_id; 233 234 35、查詢每門課程成績最好的前兩名; 235 236 select score.sid,score.course_id,score.num,T.first_num,T.second_num from score left join 237 ( 238 select 239 sid, 240 (select num from score as s2 where s2.course_id = s1.course_id order by num desc limit 0,1) as first_num, 241 (select num from score as s2 where s2.course_id = s1.course_id order by num desc limit 1,1) as second_num 242 from 243 score as s1 244 ) as T 245 on score.sid =T.sid 246 where score.num <= T.first_num and score.num >= T.second_num 247 248 36、檢索至少選修兩門課程的學生學號; 249 select student_id from score group by student_id having count(student_id) > 1 250 251 37、查詢全部學生都選修的課程的課程號和課程名; 252 select course_id,count(1) from score group by course_id having count(1) = (select count(1) from student); 253 254 38、查詢沒學過“葉平”老師講授的任一門課程的學生姓名; 255 select student_id,student.sname from score 256 left join student on score.student_id = student.sid 257 where score.course_id not in ( 258 select cid from course left join teacher on course.teacher_id = teacher.tid where tname = '張磊老師' 259 ) 260 group by student_id 261 262 39、查詢兩門以上不及格課程的同學的學號及其平均成績; 263 264 select student_id,count(1) from score where num < 60 group by student_id having count(1) > 2 265 266 40、檢索“004”課程分數小於60,按分數降序排列的同學學號; 267 select student_id from score where num< 60 and course_id = 4 order by num desc; 268 269 41、刪除“002”同學的“001”課程的成績; 270 delete from score where course_id = 1 and student_id = 2