Postgres获取搜索并向每行获取多个数组json

Question

I wants to get all subscriptions with interval "1 WEEK" from the following 'data' column

[
  {
    "id": "tran_6ac25129951962e99f28fa488993",
    "amount": 1200,
    "client": {
      "id": "client_622bdf4cce2351f28243",
      "subscription": [
        {
          "id": "sub_a67d59efb2bcbf73485a",
          "amount": 3900,
          "currency": "USD",
          "interval": "1 WEEK"
        },
        {
          "id": "sub_a67d59efb2bcbf73485a",
          "amount": 3900,
          "currency": "USD",
          "interval": "1 WEEK"
        }
      ]
    },
    "currency": "USD"
  },
  {
    "id": "tran_xxxxxxx",
    "amount": 1200,
    "client": {
      "id": "client_xxxxxx8243",
      "subscription": [
        {
          "id": "sub_xxefb2bcbf73485a",
          "amount": 3900,
          "currency": "USD",
          "interval": "1 Year"
        },
        {
          "id": "sub_yyyyyb2bcbf73485a",
          "amount": 3900,
          "currency": "USD",
          "interval": "1 WEEK"
        }
      ]
    },
    "currency": "USD"
  }
]

My table structure:

CREATE TABLE transactions
(
  data json,
  id bigserial NOT NULL,
  created_date time without time zone,
  CONSTRAINT transactions_pkey PRIMARY KEY (id)
)

In output I wants to get all "1 WEEk" subscription as rows. Above data should give 3 rows

I am using Postgres 9.3+

Answer 1

Its a nested query and I have tried writing it in as readable form as I can. I hope you can understand it -

select subscriptions from
(
    select
        cast
        (
            json_array_elements
            (
                json_array_elements(data)->'client'->'subscription'
            )
            as text
        )
        as subscriptions,

        json_array_elements
        (
            json_array_elements(data)->'client'->'subscription'
        )
        ->>'interval'
        as intervals

    from
        transactions
)
as 
    xyz
where
     intervals = '1 WEEK';

For information regarding these functions, you can refer to - http://www.postgresql.org/docs/9.3/static/functions-json.html

Edit:-

As per performance requirements, I guess this will work better than the previous one -

select * from (
  select cast (
    json_array_elements (
      json_array_elements(data)->'client'->'subscription'
    ) as text
  ) as subscription from transactions
) as temp
where subscription LIKE '%"interval":"1 WEEK"%';