[Hive_11] Hive 的高级聚合函数

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0. 说明

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1. union all

　　表联合操作

　　1.0 准备数据

　　pv.txt

2015-03    2015-03-10    cookie1
2015-03    2015-03-10    cookie5
2015-03    2015-03-12    cookie7
2015-04    2015-04-12    cookie3
2015-04    2015-04-13    cookie2
2015-04    2015-04-13    cookie4
2015-04    2015-04-16    cookie4
2015-03    2015-03-10    cookie2
2015-03    2015-03-10    cookie3
2015-04    2015-04-12    cookie5
2015-04    2015-04-13    cookie6
2015-04    2015-04-15    cookie3
2015-04    2015-04-15    cookie2
2015-04    2015-04-16    cookie1
2015-02    2015-02-16    cookie2
2015-02    2015-02-16    cookie3

　　1.1 建表

create table uv(month string,day string, id string) row format delimited fields terminated by '\t';

　　1.2 加载数据

load data local inpath '/home/centos/files/pv.txt' into table uv;

　　1.3 设置本地模式

    SET hive.exec.mode.local.auto=true;

　　1.4 统计每月用户访问量

select month ,count(distinct id) from uv group by month;

　　1.5 统计每天用户访问量

select day ,count(distinct id) from uv group by day;

　　1.6 联合查询每月每天用户访问量

select month ,count(distinct id) from uv group by month union all select day ,count(distinct id) from uv group by day;

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