mysql中新建表和理清表之间有什么联系
这篇文章给大家分享的是有关mysql中新建表和理清表之间有什么联系的内容。小编觉得挺实用的,因此分享给大家做个参考,一起跟随小编过来看看吧。
SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for baoming
-- ----------------------------
DROP TABLE IF EXISTS `baoming`;
CREATE TABLE `baoming` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`sid` int(11) DEFAULT NULL,
`kid` int(11) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=12 DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of baoming
-- ----------------------------
INSERT INTO `baoming` VALUES ('1', '1', '1');
INSERT INTO `baoming` VALUES ('2', '2', '1');
INSERT INTO `baoming` VALUES ('3', '3', '1');
INSERT INTO `baoming` VALUES ('4', '4', '2');
INSERT INTO `baoming` VALUES ('5', '5', '2');
INSERT INTO `baoming` VALUES ('6', '6', '2');
INSERT INTO `baoming` VALUES ('7', '7', '3');
INSERT INTO `baoming` VALUES ('9', '1', '3');
INSERT INTO `baoming` VALUES ('10', '3', '3');
INSERT INTO `baoming` VALUES ('11', '5', '3');
-- ----------------------------
-- Table structure for class
-- ----------------------------
DROP TABLE IF EXISTS `class`;
CREATE TABLE `class` (
`cid` int(11) NOT NULL AUTO_INCREMENT,
`level` int(11) DEFAULT NULL,
`name` varchar(255) DEFAULT NULL,
PRIMARY KEY (`cid`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of class
-- ----------------------------
INSERT INTO `class` VALUES ('1', '1', '班级1');
INSERT INTO `class` VALUES ('2', '1', '班级2');
INSERT INTO `class` VALUES ('3', '2', '班级3');
INSERT INTO `class` VALUES ('4', '3', '班级4');
-- ----------------------------
-- Table structure for ke
-- ----------------------------
DROP TABLE IF EXISTS `ke`;
CREATE TABLE `ke` (
`kid` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) DEFAULT NULL,
`tid` int(11) DEFAULT NULL,
PRIMARY KEY (`kid`)
) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of ke
-- ----------------------------
INSERT INTO `ke` VALUES ('1', '课程1', '2');
INSERT INTO `ke` VALUES ('2', '课程2', '1');
INSERT INTO `ke` VALUES ('3', '课程3', '5');
INSERT INTO `ke` VALUES ('4', '课程4', '5');
INSERT INTO `ke` VALUES ('5', '课程0', '0');
INSERT INTO `ke` VALUES ('6', '课程', null);
-- ----------------------------
-- Table structure for student
-- ----------------------------
DROP TABLE IF EXISTS `student`;
CREATE TABLE `student` (
`sid` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) DEFAULT NULL,
`sex` int(11) DEFAULT '1',
`cid` int(11) DEFAULT NULL,
PRIMARY KEY (`sid`)
) ENGINE=InnoDB AUTO_INCREMENT=11 DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of student
-- ----------------------------
INSERT INTO `student` VALUES ('1', '学生1', '1', '1');
INSERT INTO `student` VALUES ('2', '学生2', '1', '1');
INSERT INTO `student` VALUES ('3', '学生3', '2', '1');
INSERT INTO `student` VALUES ('4', '学生4', '2', '1');
INSERT INTO `student` VALUES ('5', '学生5', '1', '2');
INSERT INTO `student` VALUES ('6', '学生6', '1', '2');
INSERT INTO `student` VALUES ('7', '学生7', '2', '2');
INSERT INTO `student` VALUES ('8', '学生8', '2', '2');
INSERT INTO `student` VALUES ('9', '学生9', '1', '3');
INSERT INTO `student` VALUES ('10', '学生0', '1', '0');
-- ----------------------------
-- Table structure for teacher
-- ----------------------------
DROP TABLE IF EXISTS `teacher`;
CREATE TABLE `teacher` (
`tid` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) DEFAULT NULL,
`sex` int(11) DEFAULT '1',
PRIMARY KEY (`tid`)
) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of teacher
-- ----------------------------
INSERT INTO `teacher` VALUES ('1', '教授1', '1');
INSERT INTO `teacher` VALUES ('2', '教授2', '1');
INSERT INTO `teacher` VALUES ('3', '教授3', '2');
INSERT INTO `teacher` VALUES ('4', '教授4', '2');
INSERT INTO `teacher` VALUES ('5', '大教授', '1');
INSERT INTO `teacher` VALUES ('6', '助教', '2');
在上课的老师
SELECT DISTINCT t.name FROM ke
JOIN teacher AS t ON ke.tid=t.tid
老师和学生的对应关系
SELECT * FROM ke
JOIN teacher AS t ON ke.tid=t.tid
JOIN baoming AS b ON ke.kid=b.kid
JOIN student AS s ON b.sid=s.sid
感谢各位的阅读!关于“mysql中新建表和理清表之间有什么联系”这篇文章就分享到这里了,希望以上内容可以对大家有一定的帮助,让大家可以学到更多知识,如果觉得文章不错,可以把它分享出去让更多的人看到吧!
免责声明:
① 本站未注明“稿件来源”的信息均来自网络整理。其文字、图片和音视频稿件的所属权归原作者所有。本站收集整理出于非商业性的教育和科研之目的,并不意味着本站赞同其观点或证实其内容的真实性。仅作为临时的测试数据,供内部测试之用。本站并未授权任何人以任何方式主动获取本站任何信息。
② 本站未注明“稿件来源”的临时测试数据将在测试完成后最终做删除处理。有问题或投稿请发送至: 邮箱/279061341@qq.com QQ/279061341