查两次数据库 VS 合并查询 该怎么选择
查两次数据库 VS 合并查询 该如何选择?
打个比方
就以论坛来讲，
帖子表+会员表
才能显示 文章内容页面的基本内容
A. 一般是查询好内容，什么作者ID，再去SELECT 会员表吗?
B. 还是查询时已经同时做好合并查询 把 帖子表.作者ID = 会员表.会员ID ???
那个比较好? 大家应该是以效能作选择吧?
------解决方案--------------------
对于关系型数据库（SQL），B 是首选
对于 noSQL， A 是首选
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