hive 七-- hql執行順序

書寫順序 select - from - where - group by - having - order by 執行順序 from - where - group by - having - select - order byweb where 從右到左 過濾掉最大數量記錄的條件放在末尾 group by 從左到右 須要過濾的儘可能使用where,這樣就能group by 更少的數據,避免gr

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