回复评论的sql

/* Navicat Premium Data Transfer Source Server : 本地 Source Server Type : MySQL Source Server Version : 50536 Source Host : localhost:3306 Source Schema : datamanagement Target Server Type : MySQL Target Server Version : 50536 File Encoding : 65001 Date: 28/06/2022 20:27:33 */

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Table structure for class
-- ----------------------------
DROP TABLE IF EXISTS `class`;
CREATE TABLE `class`  (
  `cno` int(5) NOT NULL AUTO_INCREMENT COMMENT '课程号',
  `cname` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '课程名',
  PRIMARY KEY (`cno`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 3 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Compact;

-- ----------------------------
-- Records of class
-- ----------------------------
INSERT INTO `class` VALUES (1, '软工1班');
INSERT INTO `class` VALUES (2, '软工2班');

-- ----------------------------
-- Table structure for grade
-- ----------------------------
DROP TABLE IF EXISTS `grade`;
CREATE TABLE `grade`  (
  `gno` int(5) NOT NULL AUTO_INCREMENT COMMENT '成绩号',
  `kno` int(5) NULL DEFAULT NULL COMMENT '课程号',
  `sno` int(11) NULL DEFAULT NULL COMMENT '学号',
  `grade` int(5) NULL DEFAULT NULL COMMENT '成绩',
  PRIMARY KEY (`gno`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 80 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Compact;

-- ----------------------------
-- Records of grade
-- ----------------------------
INSERT INTO `grade` VALUES (7, 1, 3, 61);
INSERT INTO `grade` VALUES (8, 2, 3, 96);
INSERT INTO `grade` VALUES (9, 3, 3, 45);
INSERT INTO `grade` VALUES (10, 1, 4, 69);
INSERT INTO `grade` VALUES (11, 2, 4, 98);
INSERT INTO `grade` VALUES (12, 3, 4, 100);
INSERT INTO `grade` VALUES (13, 1, 5, 63);
INSERT INTO `grade` VALUES (14, 2, 5, 95);
INSERT INTO `grade` VALUES (15, 3, 5, 62);
INSERT INTO `grade` VALUES (16, 1, 6, 46);
INSERT INTO `grade` VALUES (17, 2, 6, 80);
INSERT INTO `grade` VALUES (18, 3, 6, 59);
INSERT INTO `grade` VALUES (22, 1, 8, 55);
INSERT INTO `grade` VALUES (23, 2, 8, 77);
INSERT INTO `grade` VALUES (24, 3, 8, 88);
INSERT INTO `grade` VALUES (25, 1, 9, 65);
INSERT INTO `grade` VALUES (26, 2, 9, 100);
INSERT INTO `grade` VALUES (27, 3, 9, 23);
INSERT INTO `grade` VALUES (28, 1, 10, 56);
INSERT INTO `grade` VALUES (29, 2, 10, 85);
INSERT INTO `grade` VALUES (30, 3, 10, 98);
INSERT INTO `grade` VALUES (31, 1, 11, 45);
INSERT INTO `grade` VALUES (32, 2, 11, 12);
INSERT INTO `grade` VALUES (33, 3, 11, 10);
INSERT INTO `grade` VALUES (34, 1, 12, 48);
INSERT INTO `grade` VALUES (35, 2, 12, 56);
INSERT INTO `grade` VALUES (36, 3, 12, 78);
INSERT INTO `grade` VALUES (37, 1, 13, 68);
INSERT INTO `grade` VALUES (38, 2, 13, 32);
INSERT INTO `grade` VALUES (39, 3, 13, 65);
INSERT INTO `grade` VALUES (40, 1, 14, 98);
INSERT INTO `grade` VALUES (41, 2, 14, 65);
INSERT INTO `grade` VALUES (42, 3, 14, 45);
INSERT INTO `grade` VALUES (44, 1, 16, 92);
INSERT INTO `grade` VALUES (45, 2, 16, 99);
INSERT INTO `grade` VALUES (46, 3, 16, 66);
INSERT INTO `grade` VALUES (47, 1, 17, 96);
INSERT INTO `grade` VALUES (48, 2, 17, 88);
INSERT INTO `grade` VALUES (49, 3, 17, 98);
INSERT INTO `grade` VALUES (50, 1, 18, 85);
INSERT INTO `grade` VALUES (51, 2, 18, 60);
INSERT INTO `grade` VALUES (52, 3, 18, 61);
INSERT INTO `grade` VALUES (59, 1, 21, 68);
INSERT INTO `grade` VALUES (60, 2, 21, 56);
INSERT INTO `grade` VALUES (61, 3, 21, 56);
INSERT INTO `grade` VALUES (62, 1, 22, 65);
INSERT INTO `grade` VALUES (63, 2, 22, 73);
INSERT INTO `grade` VALUES (64, 3, 22, 58);
INSERT INTO `grade` VALUES (65, 1, 23, 56);
INSERT INTO `grade` VALUES (66, 2, 23, 67);
INSERT INTO `grade` VALUES (67, 3, 23, 89);
INSERT INTO `grade` VALUES (71, 1, 25, 65);
INSERT INTO `grade` VALUES (72, 2, 25, 98);
INSERT INTO `grade` VALUES (73, 3, 25, 100);
INSERT INTO `grade` VALUES (74, 1, 26, 3);
INSERT INTO `grade` VALUES (75, 2, 26, 65);
INSERT INTO `grade` VALUES (76, 3, 26, 10);
INSERT INTO `grade` VALUES (77, 1, 27, 60);
INSERT INTO `grade` VALUES (78, 2, 27, 70);
INSERT INTO `grade` VALUES (79, 3, 27, 80);

-- ----------------------------
-- Table structure for kecheng
-- ----------------------------
DROP TABLE IF EXISTS `kecheng`;
CREATE TABLE `kecheng`  (
  `kno` int(5) NOT NULL AUTO_INCREMENT COMMENT '课程号',
  `kname` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '课程名',
  PRIMARY KEY (`kno`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 4 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Compact;

-- ----------------------------
-- Records of kecheng
-- ----------------------------
INSERT INTO `kecheng` VALUES (1, '高数');
INSERT INTO `kecheng` VALUES (2, '物理');
INSERT INTO `kecheng` VALUES (3, '英语');

-- ----------------------------
-- Table structure for role
-- ----------------------------
DROP TABLE IF EXISTS `role`;
CREATE TABLE `role`  (
  `rno` int(5) NOT NULL AUTO_INCREMENT COMMENT '角色号',
  `rname` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '角色名',
  PRIMARY KEY (`rno`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 4 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Compact;

-- ----------------------------
-- Records of role
-- ----------------------------
INSERT INTO `role` VALUES (1, '学生');
INSERT INTO `role` VALUES (2, '辅导员');
INSERT INTO `role` VALUES (3, '资料管理员');

-- ----------------------------
-- Table structure for student
-- ----------------------------
DROP TABLE IF EXISTS `student`;
CREATE TABLE `student`  (
  `sno` int(11) NOT NULL AUTO_INCREMENT COMMENT '学号',
  `spassword` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT '123' COMMENT '密码',
  `cno` int(5) NULL DEFAULT NULL COMMENT '班级号',
  `sname` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '姓名',
  `age` int(3) NULL DEFAULT NULL COMMENT '年龄',
  `snative` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '籍贯',
  `health` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '健康状态',
  `rno` int(5) NULL DEFAULT 1 COMMENT '角色',
  `hobby` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '爱好',
  `account` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '学生账号',
  PRIMARY KEY (`sno`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 28 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Compact;

-- ----------------------------
-- Records of student
-- ----------------------------
INSERT INTO `student` VALUES (3, '123', 1, '王五', 22, '湖南株洲', '伤心', 1, '喜欢打游戏', '103');
INSERT INTO `student` VALUES (4, '123', 1, '赵四', 21, '湖南株洲', '健康', 1, '足球', '104');
INSERT INTO `student` VALUES (5, '123', 1, '李五', 22, '湖北武汉', '健康', 1, NULL, '105');
INSERT INTO `student` VALUES (6, '123', 1, '李六', 22, '湖北武汉', '伤心', 1, '踢足球', '106');
INSERT INTO `student` VALUES (8, '123', 1, '李八', 19, '湖南株洲', '开朗', 1, NULL, '108');
INSERT INTO `student` VALUES (9, '123', 1, '李九', 25, '湖南长沙', '开朗', 1, NULL, '109');
INSERT INTO `student` VALUES (10, '123', 1, '李十', 26, '湖南长沙', '伤心', 1, NULL, '110');
INSERT INTO `student` VALUES (11, '123', 1, '李十一', 24, '湖南长沙', '开朗', 1, NULL, '111');
INSERT INTO `student` VALUES (12, '123', 1, '李十二', 24, '湖南长沙', '开朗', 1, NULL, '112');
INSERT INTO `student` VALUES (13, '123', 1, '李十三', 23, '湖南长沙', '伤心', 1, NULL, '113');
INSERT INTO `student` VALUES (14, '123', 1, '李十四', 24, '湖南长沙', '健康', 1, NULL, '114');
INSERT INTO `student` VALUES (15, '123', 2, '李十五', 22, NULL, NULL, 1, NULL, '115');
INSERT INTO `student` VALUES (16, '123', 2, '黄行', 21, '湖南怀化', '开心', 1, '看书', '116');
INSERT INTO `student` VALUES (17, '123', 1, '欧阳卡卡', NULL, NULL, NULL, 1, NULL, '117');
INSERT INTO `student` VALUES (18, '123', 2, '周小胖', NULL, NULL, NULL, 1, NULL, '118');
INSERT INTO `student` VALUES (21, '123', 2, '白系', NULL, NULL, NULL, 1, NULL, '121');
INSERT INTO `student` VALUES (22, '123', 1, '大苏打', NULL, NULL, NULL, 1, NULL, '122');
INSERT INTO `student` VALUES (23, '123', 1, '撒旦', NULL, NULL, NULL, 1, NULL, '123');
INSERT INTO `student` VALUES (25, '123', 1, '测试', NULL, NULL, NULL, 1, NULL, '125');
INSERT INTO `student` VALUES (26, '123', 1, 'cedshi', NULL, NULL, NULL, 1, NULL, '126');
INSERT INTO `student` VALUES (27, '123', 1, '小明', NULL, NULL, NULL, 1, NULL, '127');

-- ----------------------------
-- Table structure for teacher
-- ----------------------------
DROP TABLE IF EXISTS `teacher`;
CREATE TABLE `teacher`  (
  `tno` int(5) NOT NULL COMMENT '教师号',
  `account` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '教师账户',
  `tpassword` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '教师密码',
  `tname` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT '教师姓名',
  `cno` int(5) NULL DEFAULT NULL COMMENT '班级号',
  `rno` int(5) NULL DEFAULT NULL COMMENT '角色号',
  PRIMARY KEY (`tno`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Compact;

-- ----------------------------
-- Records of teacher
-- ----------------------------
INSERT INTO `teacher` VALUES (1, '1001', '123', '王辅导员', 1, 2);
INSERT INTO `teacher` VALUES (2, '1002', '123', '李辅导员', 2, 2);
INSERT INTO `teacher` VALUES (3, 'admin', 'admin', '资料管理员', NULL, 3);

SET FOREIGN_KEY_CHECKS = 1;

查询语句：

SELECT s.sno,s.spassword,s.sname,c.cname,s.age,s.snative,s.health,s.hobby,r.rname,
SUM(case when k.kname='高数' then g.grade end ) as '高数',
SUM(case when k.kname='物理' then g.grade end ) as '物理',
SUM(case when k.kname='英语' then g.grade end ) as '英语'
from class c,grade g,kecheng k,student s,role r
where s.sno=g.sno and g.kno=k.kno and s.cno=c.cno and r.rno=s.rno GROUP BY sno;

结果图