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distinct和group by 的效率比较？

WBOY
Release： 2016-06-23 14:14:28
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不是区别哈，是效率，说说为什么distinct或者group by效率就高啊，不是很明白。。。。。。。。 


回复讨论(解决方案)

distinct 和 group by 是不同的机制，分别使用在不同的场景
所以不能做效率对比

distinct 和 group by 是不同的机制，分别使用在不同的场景
所以不能做效率对比

各自机制和场景能分享下经验吗？

有没有知道的指教一下。。。

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distinct和group by 的效率比较？
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