如何在 BigQuery 的 Left Join 查询中按所有字段嵌套表进行分组？

Question

我有大约 10 个 table，我使用以下查询逐轮嵌套 table：

   R1 AS(
      SELECT ANY_VALUE(Table1).*, ARRAY_AGG(( SELECT AS STRUCT Table2.* EXCEPT(ID))) AS Table2
      FROM Table1 LEFT JOIN Table2 USING(ID)
      GROUP BY Table1.ID),

   R2 AS(
      SELECT ANY_VALUE(R1).*, ARRAY_AGG(( SELECT AS STRUCT Table3.* EXCEPT(ID))) AS Table3
      FROM R1 LEFT JOIN Table3 USING(ID)
      GROUP BY R1.ID),
...

  
   SELECT ANY_VALUE(R9).*, ARRAY_AGG(( SELECT AS STRUCT Table10.* EXCEPT(ID))) AS Table10
   FROM R9 LEFT JOIN Table10 USING(ID)

例如，在我的第一个 table 中，我可以有两个具有相同 ID 的记录，但其他一些字段会有所不同，我想将它们视为两个不同的记录，因此按所有人分组我加入时 table 的字段。然后我想对所有“sub-table”（查询中的 R tables）做同样的事情，这样我就可以按嵌套 [=22= 的所有字段进行分组]s.

我怎样才能轻松做到？

我试过了 GROUP BY Table1.*但是没用...

提前致谢

Answer 1

您似乎想要这样的东西：

select *
from table1 t1 left join
     (select t2.*
      from table2 t2
      where true
      qualify row_number() over (partition by t2.id order by t2.id) = 0
     ) t2
     using (id)

这使用 qualify 而不是 group by 来获取一行。

如果您不想要 table1 中的所有行，您也可以削减它们：

select *
from (select t1.* 
      from table1 t1
      where true
      qualify row_number() over (partition by id, col1, col2 order by id) = 1
     ) t1 left join
     (select t2.*
      from table2 t2
      where true
      qualify row_number() over (partition by t2.id order by t2.id) = 0
     ) t2
     using (id)

Answer 2

How to Group By all fields ...?
I tried GROUP BY Table1.* but it doesn't work...

考虑下面的例子

SELECT ANY_VALUE(t1).*, 
  ARRAY_AGG(( SELECT AS STRUCT t2.* EXCEPT(ID))) AS Table2
FROM Table1 t1 LEFT JOIN Table2 t2 USING(ID)
GROUP BY FORMAT('%t', t1)

Answer 3

尝试 to_json_string:

...
FROM Table1 t1
...
GROUP BY to_json_string(t1)

如何在 BigQuery 的 Left Join 查询中按所有字段嵌套表进行分组？

How to Group By all fields nested tables in a Left Join query in BigQuery?

sql

group-by

nested-table

google-bigquery