聚合重复字段：BigQuery

Question

我是 bigquery 的新手，并试图了解如何在嵌套数组上进行聚合。

数据字段看起来像这样

clientid region  m.metric  m.metric.key  m.metric.value
     1      A.     large       0            100
                              10            200
                              20            300 

如何获取按 clientid 分组的 metric.values 的聚合

谢谢！

Answer 1

尝试以下解决方案：

with sample as (
    select 1 as clientid, "A." as region, STRUCT("large" as metric, struct([0,10,20] as key, [100,200,300] as value) as x) as m
)
select clientid
, sum(metric_value)
from sample
cross join unnest(m.x.value) as metric_value
group by clientid