面试的时候被多表查询考倒了,回来练习一下,以作备用。
SET FOREIGN_KEY_CHECKS=0; -- ---------------------------- -- Table structure for `course` -- ---------------------------- DROP TABLE IF EXISTS `course`; CREATE TABLE `course` ( `cid` varchar(10) NOT NULL COMMENT '课程编号', `cname` varchar(10) NOT NULL COMMENT '课程名称', `tid` varchar(10) NOT NULL COMMENT '教师编号', PRIMARY KEY (`cid`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; -- ---------------------------- -- 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'); INSERT INTO `course` VALUES ('04', '物理', '04'); -- ---------------------------- -- Table structure for `score` -- ---------------------------- DROP TABLE IF EXISTS `score`; CREATE TABLE `score` ( `sid` varchar(10) NOT NULL COMMENT '学生编号', `cid` varchar(10) NOT NULL COMMENT '课程编号', `score` decimal(18,1) NOT NULL COMMENT '成绩' ) ENGINE=InnoDB DEFAULT CHARSET=utf8; -- ---------------------------- -- Records of score -- ---------------------------- INSERT INTO `score` VALUES ('01', '01', '80.0'); INSERT INTO `score` VALUES ('01', '02', '90.0'); INSERT INTO `score` VALUES ('01', '03', '99.0'); INSERT INTO `score` VALUES ('02', '01', '70.0'); INSERT INTO `score` VALUES ('02', '02', '60.0'); INSERT INTO `score` VALUES ('02', '03', '80.0'); INSERT INTO `score` VALUES ('03', '01', '80.0'); INSERT INTO `score` VALUES ('03', '02', '80.0'); INSERT INTO `score` VALUES ('03', '03', '80.0'); INSERT INTO `score` VALUES ('04', '01', '50.0'); INSERT INTO `score` VALUES ('04', '02', '30.0'); INSERT INTO `score` VALUES ('04', '03', '20.0'); INSERT INTO `score` VALUES ('05', '01', '76.0'); INSERT INTO `score` VALUES ('05', '02', '87.0'); INSERT INTO `score` VALUES ('06', '01', '31.0'); INSERT INTO `score` VALUES ('06', '03', '34.0'); INSERT INTO `score` VALUES ('07', '02', '89.0'); INSERT INTO `score` VALUES ('07', '03', '98.0'); -- ---------------------------- -- Table structure for `student` -- ---------------------------- DROP TABLE IF EXISTS `student`; CREATE TABLE `student` ( `sid` varchar(10) NOT NULL COMMENT '学生学号', `sname` varchar(10) NOT NULL COMMENT '学生姓名', `sage` datetime NOT NULL COMMENT '学生年龄', `ssex` varchar(10) NOT NULL COMMENT '学生性别', PRIMARY KEY (`sid`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; -- ---------------------------- -- 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', '1990-05-06 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 ('08', '王菊', '1990-01-20 00:00:00', '女'); -- ---------------------------- -- Table structure for `teacher` -- ---------------------------- DROP TABLE IF EXISTS `teacher`; CREATE TABLE `teacher` ( `tid` varchar(10) NOT NULL COMMENT '教师编号', `tname` varchar(10) DEFAULT NULL COMMENT '教师姓名', PRIMARY KEY (`tid`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8; -- ---------------------------- -- Records of teacher -- ---------------------------- INSERT INTO `teacher` VALUES ('01', '张三'); INSERT INTO `teacher` VALUES ('02', '李四'); INSERT INTO `teacher` VALUES ('03', '王五'); INSERT INTO `teacher` VALUES ('04', '三八');