Hive---CommonJoin和MapJoin区别

CommonJoin和MapJoin区别

CommonJoin即传统思路实现Join,性能较差 因为涉及到了shuffle的过程

Common join/shuffle join/reduce join (都是指同一个)

MapJoin 也叫作 boardcast join,但是MapJoin不会有reduce阶段和shuffle阶段

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转载来自:https://blog.csdn.net/lemonzhaotao/article/details/78209708

posted @ 2020-04-15 13:19  抽象Java  阅读(745)  评论(0编辑  收藏  举报