Google bigquery 带数组的不同键\u CONCAT带Struct<；字符串，字符串>；

我需要对下表中的2个数组字段执行以下操作。数组的类型为

Struct

将数组合并在一起

如果labels.key和project.key之间存在重复的键，那么我只想保留labels字段中的kvp

将组合的数组展平为带分隔符的字符串，并对它们进行排序（这样我就可以按顺序分组）

示例表数据

SELECT 1 as id, ARRAY
  [STRUCT("testlabel2" as key, "thisvalueisbetter" as value), STRUCT("testlabel3", "testvalue3")] as labels, 
  [STRUCT("testlabel2" as key, "testvalue2" as value)] as project

下面的查询执行除#2之外的所有操作，我不确定如何实现这一点。有人对如何做到这一点有什么建议吗

SELECT
  id,
  (SELECT STRING_AGG(DISTINCT CONCAT(l.key, ':', l.value) ORDER BY CONCAT(l.key, ':', l.value))
    FROM UNNEST(
    ARRAY_CONCAT(labels, project)) AS l) AS label,
FROM `mytestdata` AS t
GROUP BY id, label

当前，此查询提供以下输出：

1 testlabel2:testvalue2,testlabel2:thisvalueisbetter,testlabel3:testvalue3

但我在寻找：

1 testlabel2:thisvalueisbetter,testlabel3:testvalue3

---

下面是BigQuery标准SQL

#standardSQL
SELECT *, 
  ARRAY(
    SELECT AS STRUCT key, ARRAY_AGG(value ORDER BY source LIMIT 1)[OFFSET(0)] AS value
    FROM ( 
      SELECT 0 AS source, * FROM t.labels UNION ALL
      SELECT 1, * FROM t.project 
    ) 
    GROUP BY key
  ) AS combined_array
FROM `project.dataset.table` t  

您可以使用问题中的样本数据测试、播放上述内容，如下例所示

#standardSQL
WITH `project.dataset.table` AS (
SELECT ARRAY
  [STRUCT("testlabel2" AS key, "thisvalueisbetter" AS value), STRUCT("testlabel3", "testvalue3")] AS labels, 
  [STRUCT("testlabel2" AS key, "testvalue2" AS value)] AS project
)
SELECT *, 
  ARRAY(
    SELECT AS STRUCT key, ARRAY_AGG(value ORDER BY source LIMIT 1)[OFFSET(0)] AS value
    FROM ( 
      SELECT 0 AS source, * FROM t.labels UNION ALL
      SELECT 1, * FROM t.project 
    ) 
    GROUP BY key
  ) AS combined_array
FROM `project.dataset.table` t  

结果

或者。。。要完全匹配您的预期输出，请使用下面的

#standardSQL
SELECT *, 
  (SELECT STRING_AGG(x) FROM (
    SELECT CONCAT(key, ':', ARRAY_AGG(value ORDER BY source LIMIT 1)[OFFSET(0)]) x
    FROM ( 
      SELECT 0 AS source, * FROM t.labels UNION ALL
      SELECT 1, * FROM t.project 
    ) 
    GROUP BY key
  )) AS combined_result
FROM `project.dataset.table` t   

结果

---

您的结构是数组吗？你能提供维特的例子来重现问题吗？对不起，我现在意识到我的例子数据不是很清楚。我已经更新了帖子，添加了一个查询，我们创建了一个数据示例。有两个数组（标签和项目），都是Struct类型。我将致力于将其组合在一起，以生成带有查询的示例数据。。。对不起，我对BigQuery的了解有限，所以可能需要一些时间。太棒了。非常感谢你！我想我需要一点时间来理解它是如何工作的，但这正是我想要的：）