数据库内容预览 Course SC 表 Student 表 说明:源代码在多台设备上的数据库可视化软件(如 workbench,Navicat)测试均可用,代码运行 后,刷新下数据库就可以看到了。 源代码： create schema ch3; use ch3; SET NAMES utf8mb4; SET FOREIGN_KEY_CHECKS = 0; 

DROP TABLE IF EXISTS `course`; CREATE TABLE `course` ( `Cno` char(4) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL, `Cname` char(40) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL, `Cpno` char(4) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL, `Ccredit` smallint(6) NULL DEFAULT NULL, PRIMARY KEY (`Cno`) USING BTREE, UNIQUE INDEX `Coucno`(`Cno`) USING BTREE, INDEX `Cpno`(`Cpno`) USING BTREE, CONSTRAINT `course_ibfk_1` FOREIGN KEY (`Cpno`) REFERENCES `course` (`Cno`) ON DELETE RESTRICT ON UPDATE RESTRICT ) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci ROW_FORMAT = Dynamic; INSERT INTO `course` VALUES ('1', '数据库', '5', 4); INSERT INTO `course` VALUES ('2', '数学', NULL, 2); INSERT INTO `course` VALUES ('3', '信息系统', '1', 4); INSERT INTO `course` VALUES ('4', '操作系统', '6', 3); INSERT INTO `course` VALUES ('5', '数据结构', '7', 4); INSERT INTO `course` VALUES ('6', '数据处理', NULL, 2); INSERT INTO `course` VALUES ('7', 'PASCAL 语言', '6', 4); DROP TABLE IF EXISTS `sc`; CREATE TABLE `sc` ( `Sno` char(9) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL, `Cno` char(4) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL, `Grade` smallint(6) NULL DEFAULT NULL, PRIMARY KEY (`Sno`, `Cno`) USING BTREE, UNIQUE INDEX `SCno`(`Sno`, `Cno`) USING BTREE, INDEX `Cno`(`Cno`) USING BTREE, CONSTRAINT `sc_ibfk_1` FOREIGN KEY (`Sno`) REFERENCES `student` (`Sno`) ON DELETE RESTRICT ON UPDATE RESTRICT, CONSTRAINT `sc_ibfk_2` FOREIGN KEY (`Cno`) REFERENCES `course` (`Cno`) ON DELETE RESTRICT ON UPDATE RESTRICT ) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci ROW_FORMAT = Dynamic; INSERT INTO `sc` VALUES ('200215121', '1', 92); INSERT INTO `sc` VALUES ('200215121', '2', 85); INSERT INTO `sc` VALUES ('200215121', '3', 88); INSERT INTO `sc` VALUES ('200215122', '2', 90); INSERT INTO `sc` VALUES ('200215122', '3', 80); 

DROP TABLE IF EXISTS `student`; CREATE TABLE `student` ( `Sno` char(9) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NOT NULL, `Sname` char(20) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL, `Ssex` char(2) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL, `Sage` smallint(6) NULL DEFAULT NULL, `Sdept` char(20) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL, PRIMARY KEY (`Sno`) USING BTREE, UNIQUE INDEX `Stusno`(`Sno`) USING BTREE, UNIQUE INDEX `Sname`(`Sname`) USING BTREE ) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_0900_ai_ci ROW_FORMAT = Dynamic; INSERT INTO `student` VALUES ('200215121', '李勇', '男', 20, 'CS'); INSERT INTO `student` VALUES ('200215122', '刘晨', '女', 19, 'CS'); INSERT INTO `student` VALUES ('200215123', '王敏', '女', 18, 'MA'); INSERT INTO `student` VALUES ('200215125', '张立', '男', 19, 'IS'); SET FOREIGN_KEY_CHECKS = 1;