在bigquery中联接多个表 [英] Joining multiple tables in bigquery

问题描述

我希望能够在bigquery中联接多个表.加入两个很简单.

I would like to be able to join multiple tables in bigquery. Joining two is pretty trivial.

SELECT
t1.field1 AS field1,
t2.field2 AS field2,
t1.field3 AS field3
FROM [datasetName.tableA] t1
JOIN [datasetName.tableB] t2
ON t1.somefield = t2.anotherfield

但是，如果我想联接三个或更多表怎么办?我可以这样做吗?

But what if I want to join three or more tables? Can I just do it as

SELECT
t1.field1 AS field1,
t2.field2 AS field2,
t1.field3 AS field3,
t3.field4 as field4
FROM [datasetName.tableA] t1
JOIN [datasetName.tableB] t2
JOIN [datasetName.tableC] t3
ON t1.somefield = t2.anotherfield AND t1.somefield=t3.yetanotherfield

我已经尝试过了，但是没有用.我想我需要做类似的事情

I've tried that and it doesn't work. I think I need to do something like

SELECT 
t12.field1 as field1,
t12.field2 as field2,
t3.field3 as field3,
FROM
(SELECT
t1.field1 AS field1,
t2.field2 AS field2,
t1.field3 AS field3
FROM [datasetName.tableA] t1
JOIN [datasetName.tableB] t2
ON t1.somefield = t2.anotherfield) t12
JOIN
[datasetName.tableC] t3
ON t12.field1 = t3.field1 

但是有没有更简单的方法来做到这一点?

But is there a simpler way to accomplish this?

谢谢， 布拉德

推荐答案

我认为您正在寻找类似

SELECT
  t1.field1 AS field1,
  t2.field2 AS field2,
  t1.field3 AS field3,
  t3.field4 AS field4
FROM [datasetName.tableA] t1
JOIN [datasetName.tableB] t2 ON t1.somefield = t2.anotherfield
JOIN [datasetName.tableC] t3 ON t1.somefield = t3.yetanotherfield

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