Question

我有一个名为'receipts'的表格，其中包含以下四个值：

id              // serial
payments        // jsonb e.g. '[{'method':'card', 'amount':100.00},{'method':'cash', 'amount':150.00}]'
total_price     // decimal
status          // enum ['confirmed', 'pending']

我想要一个可以更新payments的查询，并将payments与total_price的总和进行比较。如果相同，请将status更新为“已确认”，否则请将status更新为“待定”。但是，我无法找到一种方法来获得付款总额并与total_price进行比较。

我认为代码看起来像这样：

UPDATE
  receipts
SET
  payments = receipts.payments::jsonb || '[{"method":"cash","amount": 50.00}]'::jsonb,
  status = (
    CASE WHEN
      //here to get the sum of exist payments' amount + 50.00 = receipts.total
    THEN
      'confirmed'
    ELSE
      'pending'
    END
  )
WHERE
  id = 1
RETURNING
  id,
  payments,
  total_price,
  status

Answer 1

我创建的结构有点接近：

t=# select * from so14;
 i |                                      j                                       | st
---+------------------------------------------------------------------------------+----
 1 | [{"amount": 30.00, "method": "card"}, {"amount": 11.00, "method": "cash"}]   |
 2 | [{"amount": 100.00, "method": "card"}, {"amount": 150.00, "method": "cash"}] |
(2 rows)

和这里的聚合示例有点紧密的声明：

t=# with a as (select i,st,(jsonb_array_elements(j)->>'amount')::float f from so14)
, ag as (select i, st, sum(f) from a group by i, st)
update so14 set st = sum
from ag where ag.i = so14.i
returning so14.*;
 i |                                      j                                       | st
---+------------------------------------------------------------------------------+-----
 1 | [{"amount": 30.00, "method": "card"}, {"amount": 11.00, "method": "cash"}]   | 41
 2 | [{"amount": 100.00, "method": "card"}, {"amount": 150.00, "method": "cash"}] | 250
(2 rows)

UPDATE 2

获取PostgreSQL中jsonb数组中特定属性的总和

1 个答案: