谷粒学院笔记-第二天-数据库设计

一、数据库设计

二、数据库设计规约

一、数据库设计

1、数据库

guli_edu

2、数据表

guli_edu.sql

# Host: localhost  (Version 5.7.19)
# Date: 2019-11-18 15:49:32
# Generator: MySQL-Front 6.1  (Build 1.26)#
# Structure for table "edu_chapter"
#CREATE TABLE `edu_chapter` (`id` char(19) NOT NULL COMMENT '章节ID',`course_id` char(19) NOT NULL COMMENT '课程ID',`title` varchar(50) NOT NULL COMMENT '章节名称',`sort` int(10) unsigned NOT NULL DEFAULT '0' COMMENT '显示排序',`gmt_create` datetime NOT NULL COMMENT '创建时间',`gmt_modified` datetime NOT NULL COMMENT '更新时间',PRIMARY KEY (`id`),KEY `idx_course_id` (`course_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 ROW_FORMAT=COMPACT COMMENT='课程';#
# Data for table "edu_chapter"
#INSERT INTO `edu_chapter` VALUES ('1','14','第一章：HTML',0,'2019-01-01 12:27:40','2019-01-01 12:55:30'),('1181729226915577857','18','第七章：I/O流',70,'2019-10-09 08:32:58','2019-10-09 08:33:20'),('1192252428399751169','1192252213659774977','第一章节',0,'2019-11-07 09:28:25','2019-11-07 09:28:25'),('15','18','第一章：Java入门',0,'2019-01-01 12:27:40','2019-10-09 09:13:19'),('3','14','第二章：CSS',0,'2019-01-01 12:55:35','2019-01-01 12:27:40'),('32','18','第二章：控制台输入和输出',0,'2019-01-01 12:27:40','2019-01-01 12:27:40'),('44','18','第三章：控制流',0,'2019-01-01 12:27:40','2019-01-01 12:27:40'),('48','18','第四章：类的定义',0,'2019-01-01 12:27:40','2019-01-01 12:27:40'),('63','18','第五章：数组',0,'2019-01-01 12:27:40','2019-01-01 12:27:40'),('64','18','第六章：继承',61,'2019-01-01 12:27:40','2019-10-09 08:32:47');#
# Structure for table "edu_comment"
#CREATE TABLE `edu_comment` (`id` char(19) NOT NULL COMMENT '讲师ID',`course_id` varchar(19) NOT NULL DEFAULT '' COMMENT '课程id',`teacher_id` char(19) NOT NULL DEFAULT '' COMMENT '讲师id',`member_id` varchar(19) NOT NULL DEFAULT '' COMMENT '会员id',`nickname` varchar(50) DEFAULT NULL COMMENT '会员昵称',`avatar` varchar(255) DEFAULT NULL COMMENT '会员头像',`content` varchar(500) DEFAULT NULL COMMENT '评论内容',`is_deleted` tinyint(1) unsigned NOT NULL DEFAULT '0' COMMENT '逻辑删除 1（true）已删除， 0（false）未删除',`gmt_create` datetime NOT NULL COMMENT '创建时间',`gmt_modified` datetime NOT NULL COMMENT '更新时间',PRIMARY KEY (`id`),KEY `idx_course_id` (`course_id`),KEY `idx_teacher_id` (`teacher_id`),KEY `idx_member_id` (`member_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='评论';#
# Data for table "edu_comment"
#INSERT INTO `edu_comment` VALUES ('1194499162790211585','1192252213659774977','1189389726308478977','1','小三123','http://thirdwx.qlogo.cn/mmopen/vi_32/DYAIOgq83eoj0hHXhgJNOTSOFsS4uZs8x1ConecaVOB8eIl115xmJZcT4oCicvia7wMEufibKtTLqiaJeanU2Lpg3w/132','课程很好',0,'2019-11-13 14:16:08','2019-11-13 14:16:08'),('1194898406466420738','1192252213659774977','1189389726308478977','1','小三123','http://thirdwx.qlogo.cn/mmopen/vi_32/DYAIOgq83eoj0hHXhgJNOTSOFsS4uZs8x1ConecaVOB8eIl115xmJZcT4oCicvia7wMEufibKtTLqiaJeanU2Lpg3w/132','11',0,'2019-11-14 16:42:35','2019-11-14 16:42:35'),('1194898484388200450','1192252213659774977','1189389726308478977','1','小三123','http://thirdwx.qlogo.cn/mmopen/vi_32/DYAIOgq83eoj0hHXhgJNOTSOFsS4uZs8x1ConecaVOB8eIl115xmJZcT4oCicvia7wMEufibKtTLqiaJeanU2Lpg3w/132','111',0,'2019-11-14 16:42:53','2019-11-14 16:42:53'),('1195251020861317122','1192252213659774977','1189389726308478977','1',NULL,NULL,'2233',0,'2019-11-15 16:03:45','2019-11-15 16:03:45'),('1195251382720700418','1192252213659774977','1189389726308478977','1',NULL,NULL,'4455',0,'2019-11-15 16:05:11','2019-11-15 16:05:11'),('1195252819177570306','1192252213659774977','1189389726308478977','1','小三1231','http://thirdwx.qlogo.cn/mmopen/vi_32/DYAIOgq83eoj0hHXhgJNOTSOFsS4uZs8x1ConecaVOB8eIl115xmJZcT4oCicvia7wMEufibKtTLqiaJeanU2Lpg3w/132','55',0,'2019-11-15 16:10:53','2019-11-15 16:10:53'),('1195252899448160258','1192252213659774977','1189389726308478977','1','小三1231','http://thirdwx.qlogo.cn/mmopen/vi_32/DYAIOgq83eoj0hHXhgJNOTSOFsS4uZs8x1ConecaVOB8eIl115xmJZcT4oCicvia7wMEufibKtTLqiaJeanU2Lpg3w/132','55',0,'2019-11-15 16:11:13','2019-11-15 16:11:13'),('1195252920587452417','1192252213659774977','1189389726308478977','1','小三1231','http://thirdwx.qlogo.cn/mmopen/vi_32/DYAIOgq83eoj0hHXhgJNOTSOFsS4uZs8x1ConecaVOB8eIl115xmJZcT4oCicvia7wMEufibKtTLqiaJeanU2Lpg3w/132','223344',0,'2019-11-15 16:11:18','2019-11-15 16:11:18'),('1195262128095559681','14','1189389726308478977','1','小三1231','http://thirdwx.qlogo.cn/mmopen/vi_32/DYAIOgq83eoj0hHXhgJNOTSOFsS4uZs8x1ConecaVOB8eIl115xmJZcT4oCicvia7wMEufibKtTLqiaJeanU2Lpg3w/132','11',0,'2019-11-15 16:47:53','2019-11-15 16:47:53'),('1196264505170767874','1192252213659774977','1189389726308478977','1','小三1231','http://thirdwx.qlogo.cn/mmopen/vi_32/DYAIOgq83eoj0hHXhgJNOTSOFsS4uZs8x1ConecaVOB8eIl115xmJZcT4oCicvia7wMEufibKtTLqiaJeanU2Lpg3w/132','666666',0,'2019-11-18 11:10:58','2019-11-18 11:10:58');#
# Structure for table "edu_course"
#CREATE TABLE `edu_course` (`id` char(19) NOT NULL COMMENT '课程ID',`teacher_id` char(19) NOT NULL COMMENT '课程讲师ID',`subject_id` char(19) NOT NULL COMMENT '课程专业ID',`subject_parent_id` char(19) NOT NULL COMMENT '课程专业父级ID',`title` varchar(50) NOT NULL COMMENT '课程标题',`price` decimal(10,2) unsigned NOT NULL DEFAULT '0.00' COMMENT '课程销售价格，设置为0则可免费观看',`lesson_num` int(10) unsigned NOT NULL DEFAULT '0' COMMENT '总课时',`cover` varchar(255) CHARACTER SET utf8 NOT NULL COMMENT '课程封面图片路径',`buy_count` bigint(10) unsigned NOT NULL DEFAULT '0' COMMENT '销售数量',`view_count` bigint(10) unsigned NOT NULL DEFAULT '0' COMMENT '浏览数量',`version` bigint(20) unsigned NOT NULL DEFAULT '1' COMMENT '乐观锁',`status` varchar(10) NOT NULL DEFAULT 'Draft' COMMENT '课程状态 Draft未发布  Normal已发布',`is_deleted` tinyint(3) DEFAULT NULL COMMENT '逻辑删除 1（true）已删除， 0（false）未删除',`gmt_create` datetime NOT NULL COMMENT '创建时间',`gmt_modified` datetime NOT NULL COMMENT '更新时间',PRIMARY KEY (`id`),KEY `idx_title` (`title`),KEY `idx_subject_id` (`subject_id`),KEY `idx_teacher_id` (`teacher_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 ROW_FORMAT=COMPACT COMMENT='课程';#
# Data for table "edu_course"
#INSERT INTO `edu_course` VALUES ('1192252213659774977','1189389726308478977','1178214681139539969','1178214681118568449','java基础课程：test',0.01,2,'https://guli-file-190513.oss-cn-beijing.aliyuncs.com/cover/default.gif',4,387,1,'Normal',0,'2019-11-07 09:27:33','2019-11-18 13:35:03'),('14','1189389726308478977','1101348944971091969','1101348944920760321','XHTML CSS2 JS整站制作教程课程学习',0.00,3,'http://guli-file.oss-cn-beijing.aliyuncs.com/cover/2019/03/13/d0086eb0-f2dc-45f7-bba1-744d95e5be0f.jpg',3,44,15,'Normal',0,'2018-04-02 18:33:34','2019-11-16 21:21:45'),('15','1189389726308478977','1101348944971091969','1101348944920760321','HTML5入门课程学习',0.00,23,'http://guli-file.oss-cn-beijing.aliyuncs.com/cover/2019/03/13/22997b8e-3606-4d2e-9b4f-09f48418b6e4.jpg',0,51,17,'Normal',0,'2018-04-02 18:34:32','2019-11-12 10:19:20'),('18','1189389726308478977','1178214681139539969','1178214681118568449','Java精品课程',0.01,20,'http://guli-file.oss-cn-beijing.aliyuncs.com/cover/2019/03/06/866e9aca-b530-4f71-a690-72d4a4bfd1e7.jpg',151,737,6,'Normal',0,'2018-04-02 21:28:46','2019-11-18 11:14:52');#
# Structure for table "edu_course_collect"
#CREATE TABLE `edu_course_collect` (`id` char(19) NOT NULL COMMENT '收藏ID',`course_id` char(19) NOT NULL COMMENT '课程讲师ID',`member_id` char(19) NOT NULL DEFAULT '' COMMENT '课程专业ID',`is_deleted` tinyint(3) NOT NULL DEFAULT '0' COMMENT '逻辑删除 1（true）已删除， 0（false）未删除',`gmt_create` datetime NOT NULL COMMENT '创建时间',`gmt_modified` datetime NOT NULL COMMENT '更新时间',PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 ROW_FORMAT=COMPACT COMMENT='课程收藏';#
# Data for table "edu_course_collect"
#INSERT INTO `edu_course_collect` VALUES ('1196269345666019330','1192252213659774977','1',1,'2019-11-18 11:30:12','2019-11-18 11:30:12');#
# Structure for table "edu_course_description"
#CREATE TABLE `edu_course_description` (`id` char(19) NOT NULL COMMENT '课程ID',`description` text COMMENT '课程简介',`gmt_create` datetime NOT NULL COMMENT '创建时间',`gmt_modified` datetime NOT NULL COMMENT '更新时间',PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='课程简介';#
# Data for table "edu_course_description"
#INSERT INTO `edu_course_description` VALUES ('1104870479077879809','<p>11</p>','2019-03-11 06:23:44','2019-03-11 06:23:44'),('1192252213659774977','<p>测试</p>','2019-11-07 09:27:33','2019-11-13 16:21:28'),('14','','2019-03-13 06:04:43','2019-03-13 06:05:33'),('15','','2019-03-13 06:03:33','2019-03-13 06:04:22'),('18','<p>本套Java视频完全针对零基础学员，课堂实录，自发布以来，好评如潮！Java视频中注重与学生互动，讲授幽默诙谐、细致入微，覆盖Java基础所有核心知识点，同类Java视频中也是代码量大、案例多、实战性强的。同时，本Java视频教程注重技术原理剖析，深入JDK源码，辅以代码实战贯穿始终，用实践驱动理论，并辅以必要的代码练习。</p>\n<p>------------------------------------</p>\n<p>视频特点：</p>\n<p>通过学习本Java视频教程，大家能够真正将Java基础知识学以致用、活学活用，构架Java编程思想，牢牢掌握\"源码级\"的Javase核心技术，并为后续JavaWeb等技术的学习奠定扎实基础。<br /><br />1.通俗易懂，细致入微：每个知识点高屋建瓴，深入浅出，简洁明了的说明问题<br />2.具实战性：全程真正代码实战，涵盖上百个企业应用案例及练习<br />3.深入：源码分析，更有 Java 反射、动态代理的实际应用等<br />4.登录尚硅谷官网，技术讲师免费在线答疑</p>','2019-03-06 18:06:36','2019-10-30 19:58:36');#
# Structure for table "edu_subject"
#CREATE TABLE `edu_subject` (`id` char(19) NOT NULL COMMENT '课程类别ID',`title` varchar(10) NOT NULL COMMENT '类别名称',`parent_id` char(19) NOT NULL DEFAULT '0' COMMENT '父ID',`sort` int(10) unsigned NOT NULL DEFAULT '0' COMMENT '排序字段',`gmt_create` datetime NOT NULL COMMENT '创建时间',`gmt_modified` datetime NOT NULL COMMENT '更新时间',PRIMARY KEY (`id`),KEY `idx_parent_id` (`parent_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 ROW_FORMAT=COMPACT COMMENT='课程科目';#
# Data for table "edu_subject"
#INSERT INTO `edu_subject` VALUES ('1178214681118568449','后端开发','0',1,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681139539969','Java','1178214681118568449',1,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681181483010','前端开发','0',3,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681210843137','JavaScript','1178214681181483010',4,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681231814658','云计算','0',5,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681252786178','Docker','1178214681231814658',5,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681294729217','Linux','1178214681231814658',6,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681324089345','系统/运维','0',7,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681353449473','Linux','1178214681324089345',7,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681382809602','Windows','1178214681324089345',8,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681399586817','数据库','0',9,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681428946945','MySQL','1178214681399586817',9,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681454112770','MongoDB','1178214681399586817',10,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681483472898','大数据','0',11,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681504444418','Hadoop','1178214681483472898',11,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681529610242','Spark','1178214681483472898',12,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681554776066','人工智能','0',13,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681584136193','Python','1178214681554776066',13,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681613496321','编程语言','0',14,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178214681626079234','Java','1178214681613496321',14,'2019-09-29 15:47:25','2019-09-29 15:47:25'),('1178585108407984130','Python','1178214681118568449',2,'2019-09-30 16:19:22','2019-09-30 16:19:22'),('1178585108454121473','HTML/CSS','1178214681181483010',3,'2019-09-30 16:19:22','2019-09-30 16:19:22');#
# Structure for table "edu_teacher"
#CREATE TABLE `edu_teacher` (`id` char(19) NOT NULL COMMENT '讲师ID',`name` varchar(20) NOT NULL COMMENT '讲师姓名',`intro` varchar(500) NOT NULL DEFAULT '' COMMENT '讲师简介',`career` varchar(500) DEFAULT NULL COMMENT '讲师资历,一句话说明讲师',`level` int(10) unsigned NOT NULL COMMENT '头衔 1高级讲师 2首席讲师',`avatar` varchar(255) DEFAULT NULL COMMENT '讲师头像',`sort` int(10) unsigned NOT NULL DEFAULT '0' COMMENT '排序',`is_deleted` tinyint(1) unsigned NOT NULL DEFAULT '0' COMMENT '逻辑删除 1（true）已删除， 0（false）未删除',`gmt_create` datetime NOT NULL COMMENT '创建时间',`gmt_modified` datetime NOT NULL COMMENT '更新时间',PRIMARY KEY (`id`),UNIQUE KEY `uk_name` (`name`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='讲师';#
# Data for table "edu_teacher"
#INSERT INTO `edu_teacher` VALUES ('1','张三','近年主持国家自然科学基金（6项）、江苏省重大科技成果转化项目（5项）、江苏省产学研前瞻性联合研究项目（3项）、省工业科技支撑、省高技术、省自然科学基金等省部级及其企业的主要科研项目40多个，多个项目在企业成功转化，产生了较好的经济、社会和环境效益。积极开展产学研科技合作，并与省内16家企业建立了江苏省研究生工作站，其中6家为江苏省优秀研究生工作站','高级',1,'https://guli-file-190513.oss-cn-beijing.aliyuncs.com/avatar/default.jpg',0,0,'2019-10-30 14:18:46','2019-11-12 13:36:36'),('1189389726308478977','晴天','高级讲师简介','高级讲师资历',2,'https://online-teach-file.oss-cn-beijing.aliyuncs.com/teacher/2019/10/30/de47ee9b-7fec-43c5-8173-13c5f7f689b2.png',1,0,'2019-10-30 11:53:03','2019-10-30 11:53:03'),('1189390295668469762','李刚','高级讲师简介','高级讲师',2,'https://online-teach-file.oss-cn-beijing.aliyuncs.com/teacher/2019/10/30/b8aa36a2-db50-4eca-a6e3-cc6e608355e0.png',2,0,'2019-10-30 11:55:19','2019-11-12 13:37:52'),('1189426437876985857','王二','高级讲师简介','高级讲师',1,'https://online-teach-file.oss-cn-beijing.aliyuncs.com/teacher/2019/11/08/e44a2e92-2421-4ea3-bb49-46f2ec96ef88.png',0,0,'2019-10-30 14:18:56','2019-11-12 13:37:35'),('1189426464967995393','王五','高级讲师简介','高级讲师',1,'https://online-teach-file.oss-cn-beijing.aliyuncs.com/teacher/2019/10/30/65423f14-49a9-4092-baf5-6d0ef9686a85.png',0,0,'2019-10-30 14:19:02','2019-11-12 13:37:18'),('1192249914833055746','李四','高级讲师简介','高级讲师',1,'https://online-teach-file.oss-cn-beijing.aliyuncs.com/teacher/2019/11/07/91871e25-fd83-4af6-845f-ea8d471d825d.png',0,0,'2019-11-07 09:18:25','2019-11-12 13:37:01'),('1192327476087115778','1222-12-12','1111','11',1,'https://online-teach-file.oss-cn-beijing.aliyuncs.com/teacher/2019/11/08/5805c6cd-c8ad-4a77-aafd-d2e083bfd8a4.png',0,1,'2019-11-07 14:26:37','2019-11-11 16:26:26'),('1195337453429129218','test','sdfsdf','sdfdf',1,'https://guli-file-190513.oss-cn-beijing.aliyuncs.com/avatar/default.jpg',0,1,'2019-11-15 21:47:12','2019-11-15 21:47:27');#
# Structure for table "edu_video"
#CREATE TABLE `edu_video` (`id` char(19) NOT NULL COMMENT '视频ID',`course_id` char(19) NOT NULL COMMENT '课程ID',`chapter_id` char(19) NOT NULL COMMENT '章节ID',`title` varchar(50) NOT NULL COMMENT '节点名称',`video_source_id` varchar(100) DEFAULT NULL COMMENT '云端视频资源',`video_original_name` varchar(100) DEFAULT NULL COMMENT '原始文件名称',`sort` int(10) unsigned NOT NULL DEFAULT '0' COMMENT '排序字段',`play_count` bigint(20) unsigned NOT NULL DEFAULT '0' COMMENT '播放次数',`is_free` tinyint(1) unsigned NOT NULL DEFAULT '0' COMMENT '是否可以试听：0收费 1免费',`duration` float NOT NULL DEFAULT '0' COMMENT '视频时长（秒）',`status` varchar(20) NOT NULL DEFAULT 'Empty' COMMENT 'Empty未上传 Transcoding转码中  Normal正常',`size` bigint(20) unsigned NOT NULL DEFAULT '0' COMMENT '视频源文件大小（字节）',`version` bigint(20) unsigned NOT NULL DEFAULT '1' COMMENT '乐观锁',`gmt_create` datetime NOT NULL COMMENT '创建时间',`gmt_modified` datetime NOT NULL COMMENT '更新时间',PRIMARY KEY (`id`),KEY `idx_course_id` (`course_id`),KEY `idx_chapter_id` (`chapter_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 ROW_FORMAT=COMPACT COMMENT='课程视频';#
# Data for table "edu_video"
#INSERT INTO `edu_video` VALUES ('1182499307429339137','18','32','第一节','','',0,0,0,0,'',0,1,'2019-10-11 11:32:59','2019-10-11 11:57:38'),('1185312444399071234','14','1','12','','',0,0,0,0,'Empty',0,1,'2019-10-19 05:51:23','2019-10-19 05:51:33'),('1189434737808990210','18','44','测试','','',1,0,0,0,'Empty',0,1,'2019-10-30 14:51:55','2019-10-30 14:51:55'),('1189471423678939138','18','1181729226915577857','test','2b887dc9584d4dc68908780ec57cd3b9','视频',1,0,0,0,'Empty',0,1,'2019-10-30 17:17:41','2019-10-30 17:17:41'),('1189476403626409986','18','1181729226915577857','22','5155c73dc112475cbbddccf4723f7cef','视频.mp4',0,0,0,0,'Empty',0,1,'2019-10-30 17:37:29','2019-10-30 17:37:29'),('1192252824606289921','1192252213659774977','1192252428399751169','第一课时','756cf06db9cb4f30be85a9758b19c645','eae2b847ef8503b81f5d5593d769dde2.mp4',0,0,0,0,'Empty',0,1,'2019-11-07 09:29:59','2019-11-07 09:29:59'),('1192628092797730818','1192252213659774977','1192252428399751169','第二课时','2a02d726622f4c7089d44cb993c531e1','eae2b847ef8503b81f5d5593d769dde2.mp4',0,0,1,0,'Empty',0,1,'2019-11-08 10:21:10','2019-11-08 10:21:22'),('1192632495013380097','1192252213659774977','1192252428399751169','第三课时','4e560c892fdf4fa2b42e0671aa42fa9d','eae2b847ef8503b81f5d5593d769dde2.mp4',0,0,1,0,'Empty',0,1,'2019-11-08 10:38:40','2019-11-08 10:38:40'),('1194117638832111617','1192252213659774977','1192252428399751169','第四课时','4e560c892fdf4fa2b42e0671aa42fa9d','eae2b847ef8503b81f5d5593d769dde2.mp4',0,0,0,0,'Empty',0,1,'2019-11-12 13:00:05','2019-11-12 13:00:05'),('1196263770832023554','1192252213659774977','1192252428399751169','第五课时','27d21158b0834cb5a8d50710937de330','eae2b847ef8503b81f5d5593d769dde2.mp4',5,0,0,0,'Empty',0,1,'2019-11-18 11:08:03','2019-11-18 11:08:03'),('17','18','15','第一节：Java简介','196116a6fee742e1ba9f6c18f65bd8c1','1',1,1000,1,100,'Draft',0,1,'2019-01-01 13:08:57','2019-10-11 11:26:39'),('18','18','15','第二节：表达式和赋值语句','2d99b08ca0214909899910c9ba042d47','7 - How Do I Find Time for My ',2,999,1,100,'Draft',0,1,'2019-01-01 13:09:02','2019-03-08 03:30:27'),('19','18','15','第三节：String类','51120d59ddfd424cb5ab08b44fc8b23a','eae2b847ef8503b81f5d5593d769dde2.mp4',3,888,0,100,'Draft',0,1,'2019-01-01 13:09:05','2019-11-12 12:50:45'),('20','18','15','第四节：程序风格','2a38988892d84df598752226c50f3fa3','00-day10总结.avi',4,666,0,100,'Draft',0,1,'2019-01-01 13:09:05','2019-10-11 09:20:09');

二、数据库设计规约

以下规约只针对本模块，更全面的文档参考《阿里巴巴Java开发手册》：五、MySQL数据库

1、库名与应用名称尽量一致

2、表名、字段名必须使用小写字母或数字，禁止出现数字开头，

3、表名不使用复数名词

4、表的命名最好是加上“业务名称_表的作用”。如，edu_teacher

5、表必备三字段：id, gmt_create, gmt_modified

说明：其中 id 必为主键，类型为 bigint unsigned、单表时自增、步长为 1。（如果使用分库分表集群部署，则id类型为verchar，非自增，业务中使用分布式id生成器） gmt_create, gmt_modified 的类型均为 datetime 类型，前者现在时表示主动创建，后者过去分词表示被动更新。

6、单表行数超过 500 万行或者单表容量超过 2GB，才推荐进行分库分表。说明：如果预计三年后的数据量根本达不到这个级别，请不要在创建表时就分库分表。

7、表达是与否概念的字段，必须使用 is_xxx 的方式命名，数据类型是 unsigned tinyint （1 表示是，0 表示否）。说明：任何字段如果为非负数，必须是 unsigned。注意：POJO 类中的任何布尔类型的变量，都不要加 is 前缀。数据库表示是与否的值，使用 tinyint 类型，坚持 is_xxx 的命名方式是为了明确其取值含义与取值范围。正例：表达逻辑删除的字段名 is_deleted，1 表示删除，0 表示未删除。

8、小数类型为 decimal，禁止使用 float 和 double。说明：float 和 double 在存储的时候，存在精度损失的问题，很可能在值的比较时，得到不正确的结果。如果存储的数据范围超过 decimal 的范围，建议将数据拆成整数和小数分开存储。

9、如果存储的字符串长度几乎相等，使用 char 定长字符串类型。

10、varchar 是可变长字符串，不预先分配存储空间，长度不要超过 5000，如果存储长度大于此值，定义字段类型为 text，独立出来一张表，用主键来对应，避免影响其它字段索引效率。

11、唯一索引名为 uk_字段名；普通索引名则为 idx_字段名。说明：uk_ 即 unique key；idx_ 即 index 的简称

12、不得使用外键与级联，一切外键概念必须在应用层解决。外键与级联更新适用于单机低并发，不适合分布式、高并发集群；级联更新是强阻塞，存在数据库更新风暴的风险；外键影响数据库的插入速度。