mysql中聚集索引的含义是什么[复制]

This question already has an answer here:

Mysql How do you create a clustered index? 4 answers
What do Clustered and Non clustered index actually mean? 10 answers

I have confusion in clustered index in database concept. I completely read about indexing. So i understood the indexing. But i don't know what is the proper meaning of clustered index. Can any one help what is clustered index?

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