标签：count
COUNT(*) vs COUNT(col) in mysql

Looking at how people are using COUNT(*) and COUNT(col) it looks like most of them think they are synonyms and just using what they happen to like, while there is substantial difference in performance and even query result.

本日志由 flyinweb 于 2011-08-25 09:52:13 发表到 数据库技术 中，目前已经被浏览 685 次，评论 0 次；

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