在 Big Query 中聚合或嵌套 STRUCT SQL

Question

我有以下 table:

ClientId (Integer)	EmailCampaign (String)	CampaignDetails (STRUCT)
235	Campaign 32	SentOn: 2020-01-22, Email addresses:2, SuccessRate:1
235	Campaign 22	SentOn: 2021-02-02, Email addresses:2, SuccessRate:0.5
235	Campaign 23	SentOn: 2022-05-11, Email addresses:2, SuccessRate:0.3
235	Campaign 55	SentOn: 2020-11-03, Email addresses:2, SuccessRate:0.9
122	Campaign 22	SentOn: 2022-01-03, Email addresses:2, SuccessRate:0.9

而且我想以一种方式处理数据，每个客户只有一行，它看起来像这样：

ClientId (Integer)	CampaignDetails (NESTED STRUCTs)
235	EmailCampaign: Campaign 32, (SentOn: 2020-01-22, Email addresses:2, SuccessRate:1), EmailCampaign: Campaign 22, (SentOn: 2021-02-02, Email addresses:2, SuccessRate:0.5), ...
122	EmailCampaign: Campaign 22, (SentOn: 2022-01-03, Email addresses:2, SuccessRate:0.9)

但是，我发现自己很难在客户端级别聚合 STRUCT。知道解决此问题的最佳方法是什么吗？

结果 table 应该允许我们使用以下方法查询它：

SELECT * 
FROM outputTable 
WHERE ClientId = 235 AND CampaignDetails.EmailCampaign = 'Campaign 22'

Answer 1

Hi Jaytiger! Unfortunately this solution nests the structs in an array, and I cant query it properly to find the right email campaign using array indexes

CREATE TEMP TABLE outputTable  AS
  WITH sample AS (
  SELECT 235 AS ClientId, 'Campaign 32' AS EmailCampaign,
         STRUCT('2020-01-22' AS SentOn, '2' AS Email, 1.0 AS SuccessRate) AS CampaignDetails
   UNION ALL
  SELECT 235 AS ClientId, 'Campaign 22' AS EmailCampaign,
         STRUCT('2020-02-22' AS SentOn, '2' AS Email, 0.5 AS SuccessRate) AS CampaignDetails
   UNION ALL
  SELECT 122 AS ClientId, 'Campaign 22' AS EmailCampaign,
         STRUCT('2020-02-22' AS SentOn, '2' AS Email, 0.9 AS SuccessRate) AS CampaignDetails
  )
SELECT ClientId, ARRAY_AGG(STRUCT(EmailCampaign, CampaignDetails)) AS CampaignDetails 
  FROM sample 
 GROUP BY 1
;

-- You can query nested structures using UNNEST()
SELECT * FROM outputTable, UNNEST(CampaignDetails) cd 
  WHERE ClientId = 235 AND cd.EmailCampaign = 'Campaign 22'
;

输出：

在 Big Query 中聚合或嵌套 STRUCT SQL

Aggregating or nesting STRUCTs in Big Query SQL

sql

google-bigquery