如何在postgres json列中查询嵌套数组？

一尘不染

如何在postgres json列中查询嵌套数组？

json

我在postgres
json列中有一些类似于下面的json的json。我正在尝试查询它以识别一些输入错误的数据。我基本上是在寻找房屋描述与房屋号码相同的地址。我不太想办法。

{
  "timestamp": "2014-10-23T16:15:28+01:00",
  "schools": [
    {
    "school_id": "1",
    "addresses": [
      {
        "town": "Birmingham",
        "house_description": "1",
        "street_name": "Parklands",
        "addr_id": "4",
        "postcode": "B5 8KL",
        "house_no": "1",
        "address_type": "UK"
      },
      {
        "town": "Plymouth",
        "house_description": "Flat a",
        "street_name": "Fore Street",
        "addr_id": "2",
        "postcode": "PL9 8AY",
        "house_no": "15",
        "address_type": "UK"
      }
    ]
  },
  {
    "school_id": "2",
    "addresses": [
      {
        "town": "Coventry",
        "street_name": "Shipley Way",
        "addr_id": "19",
        "postcode": "CV8 3DL",
        "house_no": "662",
        "address_type": "UK"
      }
    ]
  }
  ]
}

我写了这个sql，它将找到数据匹配的地方：

select *
FROM title_register_data
where address_data->'schools'->0->'addresses'->0->>'house_description'= 
address_data->'schools'->0->'addresses'->0->>'house_no'

显然，这仅适用于第一所学校的第一地址。有没有办法查询每所学校的所有地址？

阅读 258

2020-07-27

共1个答案

一尘不染

jsonb_array_elements()在横向联接中使用的次数与要比较的json数组的深度一样多：

select 
    schools->>'school_id' school_id,
    addresses->>'addr_id' addr_id,
    addresses->>'house_description' house_description,
    addresses->>'house_no' house_no
from title_register_data,
jsonb_array_elements(address_data->'schools') schools,
jsonb_array_elements(schools->'addresses') addresses
where addresses->>'house_description' = addresses->>'house_no';

 school_id | addr_id | house_description | house_no 
-----------+---------+-------------------+----------
 1         | 4       | 1                 | 1
(1 row)

2020-07-27