HIve-Grouping sets用法

grouping sets不需要把所有的列名进行组合，把需要的进行组合就可以了；(dt),(dt, lead_pro_name),(dt, lead_city_name)，这里加了三种情况，分别表示的是每天全国维度，每天省份维度，每天城市维度，如果再加(dt, lead_pro_name，lead_city_name)，这个就是和(dt, lead_city_name)一样的情况了，会造成重复，所以写的时候先考虑清楚，是需要将哪几种维度的放在一起。

select
    dt,
    lead_pro_name,
    lead_city_name,
    case
        when lead_pro_name is null
        and lead_city_name is null then '全国'
        when lead_pro_name is not null
        and lead_city_name is null then '省份'
        when lead_city_name is not null then '城市'
    end as `维度`,
    sum(sale_cnt) as `销量`
from
    wujie.dm_cx_trd_multi_order_di
where
    dt >= date_sub(current_date, 2)
    and is_td_valid_pay = 1
group by
    dt,
    lead_pro_name,
    lead_city_name grouping sets(
        (dt),
        (dt, lead_pro_name),
        (dt, lead_city_name)
    );