Big Query - Group By Clause 不适用于 NEST()

Question

这是他们 public 测试数据的再现 -

SELECT corpus, NEST(word) 
FROM [publicdata:samples.shakespeare] 
GROUP BY corpus 
LIMIT 1000

Row corpus f0_
1 1kinghenryiv brave
2 1kinghenryiv profession
3 1kinghenryiv treason

谁能告诉我我做错了什么？

Answer 1

没问题
每 https://cloud.google.com/bigquery/query-reference#aggfunctions

BigQuery automatically flattens query results, so if you use the NEST function on the top level query, the results won't contain repeated fields. Use the NEST function when using a subselect that produces intermediate results for immediate use by the same query.

返回的行数证明了这一点（查询中为 1000 - 但结果为 41852，因为它被展平了：

您还可以运行在下方查询以查看 NEST() 是否确实有效：

SELECT corpus, COUNT(1) AS cnt 
FROM (
  SELECT corpus, NEST(word) 
  FROM [publicdata:samples.shakespeare] 
  GROUP BY corpus 
  LIMIT 1000
)
GROUP BY corpus

Big Query - Group By Clause 不适用于 NEST()

Big Query - Group By Clause not working with NEST()

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