求助：回复数、列表分页等几个常见数据库设计的问题
我建一个博客，简要的需求如下：在文章(Article)列表页要显示评论数量，文章列表要分页显示，评论(Comment)列表也要分页显示（评论列表通过ajax分页显示）。
因为没做过多少项目，因此想问几个问题：
1.像评论数量一般是作为article表的一个字段还是在执行的时候通过select count来实现呢？如果是通过select count实现那么每次在文章列表显示N条文章，那执行N条select count来查询回复数量会不会降低性能？
2.假设博客首页有许多文章列表块（如：周排行、日排行、最近点击排行、相关文章、最新文章、最新评论等），除了对一部分列表块（如周排行、日排行这些较少更新的部分）做缓存外，一次http请求执行有10条select语句（所有的select语句都已经经过优化）算不算多了呢？
------最佳解决方案--------------------
1、应该用一个字段存储
2、原则上是尽量减少查询。但如果你的博客访问量并不大这都不算什么。
------其他解决方案--------------------
应该用1个字段存储，但最好做个初始化程序重新数数，否则时间长了可能会有误差。
如果不想用字段存，可以用缓存
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