目录
1.概述
GROUPING SETS,GROUPING__ID,CUBE,ROLLUP
这几个分析函数通常用于OLAP中,不能累加,而且需要根据不同维度上钻和下钻的指标统计,比如,分小时、天、月的UV数。
2.数据准备
2.1数据格式
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
2.2创表语句
use cookie;
drop table if exists cookie5;
create table cookie5(month string, day string, cookieid string)
row format delimited fields terminated by ',';
load data local inpath "/home/hadoop/cookie5.txt" into table cookie5;
select * from cookie5;
3.GROUPING SETS和GROUPING__ID
说明:在一个GROUP BY查询中,根据不同的维度组合进行聚合,等价于将不同维度的GROUP