Hive中的COLLECT_SET(),保持重复吗? [英] COLLECT_SET() in Hive, keep duplicates?
本文介绍了Hive中的COLLECT_SET(),保持重复吗?的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
有没有办法将重复集合保存在Hive中的收集集合中,或者模拟Hive使用其他方法提供的聚合集合类型?我想将具有相同关键字的列中的所有项目汇总到一个数组中,并重复。
IE:
hash_id | num_of_cats
=====================
ad3jkfk 4
ad3jkfk 4
ad3jkfk 2
fkjh43f 1
fkjh43f 8
fkjh43f 8
rjkhd93 7
rjkhd93 4
rjkhd93 7
应该返回:
hash_agg | cats_aggregate
===========================
ad3jkfk数组< int>(4,4,2)
fkjh43f数组< int>(1,8,8)
rjkhd93数组< int>(7,4,7)
解决方案
尝试在Hive 0.13.0之后使用COLLECT_LIST(col)
SELECT
hash_id,COLLECT_LIST(num_of_cats)AS aggr_set
FROM
表名
WHERE
blablabla
GROUP BY
hash_id
;
Is there a way to keep the duplicates in a collected set in Hive, or simulate the sort of aggregate collection that Hive provides using some other method? I want to aggregate all of the items in a column that have the same key into an array, with duplicates.
I.E.:
hash_id | num_of_cats
=====================
ad3jkfk 4
ad3jkfk 4
ad3jkfk 2
fkjh43f 1
fkjh43f 8
fkjh43f 8
rjkhd93 7
rjkhd93 4
rjkhd93 7
should return:
hash_agg | cats_aggregate
===========================
ad3jkfk Array<int>(4,4,2)
fkjh43f Array<int>(1,8,8)
rjkhd93 Array<int>(7,4,7)
解决方案
Try to use COLLECT_LIST(col) after Hive 0.13.0
SELECT
hash_id, COLLECT_LIST(num_of_cats) AS aggr_set
FROM
tablename
WHERE
blablabla
GROUP BY
hash_id
;
这篇关于Hive中的COLLECT_SET(),保持重复吗?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!
查看全文