SQL - 从数组中提取 JSON

Question

我正在使用 Google BigQuery 编写一些查询。我想从数组中提取 JSON。不知何故，我可以提取它。 @Mikhail Berlyant 帮助了我 here。但现在问题在于从没有重复的数组中提取 JSON。

当前结构：

我试过了：

WITH
  cte AS (
  SELECT
    labels,
    cost
  FROM
    BILLING.gcp_billing_export_v1)
SELECT
  la,
  cost
FROM
  cte,
  UNNEST(labels) AS la

查看成本框，COST 值重复了两次，因为我们在数组中有 2 个 KEY, VALUE 对。

因此，在与la.key 的组一起做sum(cost) 时，我得到了错误的值。

我正在寻找的是，

谁能帮我解决这个问题？

Answer 1

以下是 BigQuery 标准 SQL

#standardSQL
SELECT 
  description, 
  ARRAY(
    SELECT AS STRUCT 
      JSON_EXTRACT_SCALAR(kv, '$.key') key, 
      JSON_EXTRACT_SCALAR(kv, '$.value') value 
    FROM UNNEST(SPLIT(labels, '},{')) kv_temp, 
    UNNEST([CONCAT('{', REGEXP_REPLACE(kv_temp, r'^\[{|}]$', ''), '}')]) kv
  ) labels,
  cost
FROM `project.dataset.table`   

您可以使用以下问题中的虚拟数据摘录来测试和玩上面的内容

#standardSQL
WITH `project.dataset.table` AS (
  SELECT 'aaa' description, '[{"key":"application","value":"scaled-server"},{"key":"department","value":"hrd"}]' labels, 0.323316 cost UNION ALL
  SELECT 'bbb' description, '[{"key":"application2","value":"scaled-server2"},{"key":"department2","value":"hrd2"}]' labels, 0.342825 cost 
)
SELECT 
  description, 
  ARRAY(
    SELECT AS STRUCT 
      JSON_EXTRACT_SCALAR(kv, '$.key') key, 
      JSON_EXTRACT_SCALAR(kv, '$.value') value 
    FROM UNNEST(SPLIT(labels, '},{')) kv_temp, 
    UNNEST([CONCAT('{', REGEXP_REPLACE(kv_temp, r'^\[{|}]$', ''), '}')]) kv
  ) labels,
  cost
FROM `project.dataset.table`   

结果

Row description labels.key      labels.value    cost     
1   aaa         application     scaled-server   0.323316     
                department      hrd      
2   bbb         application2    scaled-server2  0.342825     
                department2     hrd2