Question

如何从＆＃34; SUM(amount)＆＃34;中获取汇总refunds postgres json中的数组选择以下是我的数据模式和结构：

表名：transactions

列名：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

请提供全球解决方案，而不是静态数据

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;

如果您需要知道查询是如何构建的：

1.

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

这将从交易表中找到的数组 -> 中选择所有元素作为 JSON 对象（通过 refunds 完成）并将其存储在新表 AllRefunds 中。这个新表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;

这里添加的（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 对象。因此，我们将字段 amount 作为一个带有 ->> 的简单字符串返回，然后我们将其转换为整数并 SUM 所有条目。

获取Postgres NOSQL json数据中json数组的总和

2 个答案: