我们在练习开放微信公共平台的应用
我们准备是将课程表（html格式 课程表用table排版的）从学校服务器拿回来之后
通过PHP的split等函数对获取回来的课表的字符串进行操作
将每一节课的信息 提取出来保存到数据库中
根据用户不同的周数要求 用PHP 重新排版一个课程表出来（只显示某一周的课程 学校原来的课程表是整一个学期的课程都在一张表里的） 将新的课程表的url 返回给微信用户
我负责数据库建表 我准备建3个表
表一 微信ID 学号 教务密码（用作以后再次向校方服务器请求课表用）
表二 微信ID 周数 课程名
表三 微信ID 课程名 上课星期 上课节数 上课地点 上课老师
（对表二和表三 通过SQL查询 得出对应某一周的课程表）
这里就有个问题了 因为原来的课程的周数是1-8周这样的表示方式
我应该怎样才能
1.在数据库里只用一行的表示出来呢
2.还得能做到对表二和表三（查询的时候还得是只查单周的 这样才能提取出仅仅是某一周的课程数据） 通过SQL查询 得出对应某一周的课程表的效果
感觉这个问题无解 有也是很麻烦的解法
我应该乖乖的每一周做一条记录吗 感觉这样数据库会很冗余呀
回复内容：
我们在练习开放微信公共平台的应用
我们准备是将课程表（html格式 课程表用table排版的）从学校服务器拿回来之后
通过PHP的split等函数对获取回来的课表的字符串进行操作
将每一节课的信息 提取出来保存到数据库中
根据用户不同的周数要求 用PHP 重新排版一个课程表出来（只显示某一周的课程 学校原来的课程表是整一个学期的课程都在一张表里的） 将新的课程表的url 返回给微信用户
我负责数据库建表 我准备建3个表
表一 微信ID 学号 教务密码（用作以后再次向校方服务器请求课表用）
表二 微信ID 周数 课程名
表三 微信ID 课程名 上课星期 上课节数 上课地点 上课老师
（对表二和表三 通过SQL查询 得出对应某一周的课程表）
这里就有个问题了 因为原来的课程的周数是1-8周这样的表示方式
我应该怎样才能
1.在数据库里只用一行的表示出来呢
2.还得能做到对表二和表三（查询的时候还得是只查单周的 这样才能提取出仅仅是某一周的课程数据） 通过SQL查询 得出对应某一周的课程表的效果
感觉这个问题无解 有也是很麻烦的解法
我应该乖乖的每一周做一条记录吗 感觉这样数据库会很冗余呀
表1 微信ID 学号 密码（用md5或者sha1加密）
表2 微信ID 课程ID
表3 课程ID 上课时间 课程名 上课节数 上课地点 上课老师
表1和表2以微信ID为外键连接
表2和表3以课程ID为外键连接
表1就是记录人的信息，表3是记录课程的信息，人和课程是多对多的关系，所以这里表2相当于是张连接表
表3存上课时间的好处就是，时间戳和周数应该是可以直接转的，所以在sql查询的时候其实就是7天范围的一个查找，还可以按照时间排序（因为你输出课程表肯定得要顺序的吧）然后几乎没有冗余数据
如果表3中，同一课程一周出现多次，课程名，上课地点，上课老师可能还是重复的，可以考虑再拆一张表。（不过如果不是学校作业我觉得就不用拆了...）
PS：密码记得用md5或者sha1或者别的什么加密。
我把表2和3合并了
微信ID 课程名 上课星期 上课节数 上课地点 上课老师 开始上课周数 结束上课周数
如果一个课程是1-8周的话 在数据库里就对应两个字段 开始上课周数 结束上课周数 数值分别是 1 8
在查询的时候 用当前的周数和 开始上课周数 结束上课周数 做大小比较就好了
感觉我还是语死早
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