获取 Postgres NOSQL json 数据中 json 数组的总和

Question

如何从 postgres json select 中的“refunds”数组获取聚合 SUM(amount) 以下是我的数据模式和结构：

Table 姓名：transactions

列名称：data

{
  "id": "tran_6ac25129951962e99f28fa488993",
  "amount": 1200,
  "origin_amount": 3900,
  "status": "partial_refunded",
  "description": "Subscription#sub_a67d59efb2bcbf73485a ",
  "livemode": false,
  "refunds": [
    {
      "id": "refund_ee4192ffb6d2caa490a1",
      "amount": 1200,
      "status": "refunded",
      "created_at": 1426412340,
      "updated_at": 1426412340,
    },
    {
      "id": "refund_0e4a34e4ee7281d369df",
      "amount": 1500,
      "status": "refunded",
      "created_at": 1426412353,
      "updated_at": 1426412353,
    }
  ]
}

输出应该是：1200+1500 = 2700

Output
|---------
|total
|---------
|2700

请提供全局解决方案，不要使用静态数据

Answer 1

这应该适用于 9.3+

WITH x AS( SELECT
'{
  "id": "tran_6ac25129951962e99f28fa488993",
  "amount": 1200,
  "origin_amount": 3900,
  "status": "partial_refunded",
  "description": "Subscription#sub_a67d59efb2bcbf73485a ",
  "livemode": false,
  "refunds": [
    {
      "id": "refund_ee4192ffb6d2caa490a1",
      "amount": 1200,
      "status": "refunded",
      "created_at": 1426412340,
      "updated_at": 1426412340
    },
    {
      "id": "refund_0e4a34e4ee7281d369df",
      "amount": 1500,
      "status": "refunded",
      "created_at": 1426412353,
      "updated_at": 1426412353
    }
  ]
}'::json as y),
refunds AS(
SELECT json_array_elements(y->'refunds') as j FROM x)
SELECT sum((j->>'amount')::int) FROM refunds;

Answer 2

WITH AllRefunds AS ( SELECT jsonb_array_elements(data->'refunds') AS refund FROM transactions)
SELECT SUM( CAST ( refund ->> 'amount' AS INTEGER )) FROM AllRefunds;

如果您需要了解如何构建查询：

1.

WITH AllRefunds AS ( SELECT jsonb_array_elements(data->'refunds') FROM transactions)
SELECT * FROM AllRefunds;

这从数组 refunds 中选择在交易 table 中找到的所有元素作为 JSON 对象（通过 -> 完成）并将其存储在新的 table AllRefunds。这个新的 table 只包含一个未命名的列。

2.

WITH AllRefunds AS ( SELECT jsonb_array_elements(data->'refunds') AS refund FROM transactions)
SELECT * FROM AllRefunds;

此处添加的（第二个）AS 将 AllRefunds 中当前未命名的列重命名为 refund

3.

WITH AllRefunds AS ( SELECT jsonb_array_elements(data->'refunds') AS refund FROM transactions)
SELECT SUM( CAST ( refund ->> 'amount' AS INTEGER )) FROM AllRefunds;

我们的数组条目是 JSON 个对象。所以我们 return 字段 amount 作为一个带有 ->> 的简单字符串，然后我们将其转换为整数和 SUM 所有条目。

获取 Postgres NOSQL json 数据中 json 数组的总和

Get aggregate sum of json array in Postgres NOSQL json data

postgresql

json

nosql