一直有一个问题，基本，但是还是想弄清楚。mysql读取数据库存储。。。铛铛铛
自知自己技术一般，所以大虾别喷。
就是假如有一个总记录 A 表,里面有各种字段，sid title content link....
然后有一个个人记录表 B 表 ，字段：id name sid(A表的sid) 来记录这个人所拥有的A表中的数据。
那现在问题出现了，假如B表”张三“有10条A表记录，我是把 10个sid用一个符号组合在一起存入B表的sid呢。还是生成10条记录存入B表呢？
考虑到往出取的时候 第1种方法自然是用explode 来分割B表sid，然后进行循环再查询A表来取出数据。 第2种方法就是直接将该id的所有记录查出循环出来。
那么到底是哪种方法好？ 从 数据库 程序各方面所下。 在下不知道阐述的怎么样，还望指教。。。
------解决方案--------------------
1、可以用一个符号（,）组合在一起存入B表的sid，查询时 find_in_set(A.sid,B.sid)
这种情况要求B.sid足够大，假如不是10条而是1000条，10000条呢
2、可以每个sid一条存入B，查询时 A.sid=B.sid
看着很傻，但很有效
3、以上的方案都是假定A.sid是公有的，即多个用户可以拥有同一个A.sid。比如：好友、关注
如果A.sid是用户私有的，比如发帖
那就应该在A中增加一个uid字段来记录归属
------解决方案--------------------
第二种简单，第explode的话，还要自己做很多操作
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