group by by bigquery标准sql并且无法获得唯一记录

Question

在＆＃34;组中获取错误错误：SELECT列表表达式引用列id_coupon既不是分组也不是聚合在... ＆＃34;

在我的表格中＃34; table_name＆＃34; id_coupon为每个id_discount都有多个条目。意味着id_discount不是唯一的，id_coupon是唯一的。我想只针对每个id_discount获得一个id_coupon ...

SELECT
  id_discount,
  id_coupon
FROM
  abbccc.discounts.table_name
  GROUP BY id_discount

Answer 1

SELECT
  id_discount,
  MIN(id_coupon) as id_coupon
FROM abbccc.discounts.table_name
GROUP BY id_discount