如何将此 JSON 数据导入 postgresql 表？

Posted 2023-02-16

【中文标题】如何将此 JSON 数据导入 postgresql 表？

【英文标题】：How to import this JSON data into a postgresql table?

【发布时间】：2021-10-08 05:18:34

【问题描述】：

我有以下 JSON：

   "ticket":
      "ticket":"61086762bb68d90001148fe9",
      "timestamp":"2021-08-02T18:45:06.581-0300"
   ,
   "serie":
      "measurement":
         "nemo":"RT",
         "description":"Real Time"
      ,
      "tagSet":
         "Granularity":"1h",
         "Facility":"382"
      ,
      "fieldSet":
         "EnvTemperature":"°C",
         "HorizIrrad":"W/m²"
      
   ,
   "values":[
      
         "tagSet":
            "Facility":"382",
            "Granularity":"1h"
         ,
         "fieldSet":
            "EnvTemperature":7.0,
            "HorizIrrad":632.0
         ,
         "time":"2021-08-02T11:00:00.000-0300"
      ,
      
         "tagSet":
            "Facility":"382",
            "Granularity":"1h"
         ,
         "fieldSet":
            "EnvTemperature":10.0,
            "HorizIrrad":884.0
         ,
         "time":"2021-08-02T12:00:00.000-0300"
      
   ]

我想知道如何将“值”部分中的“EnvTemperature”、“HorizIrrad”和“时间”导入如下表格：

time	EnvTemperature	HorizIrrad
2021-08-02 11:00:00	7	632
2021-08-02 12:00:00	10	884

或者像这样：

time	Fieldset	value
2021-08-02 11:00:00	EnvTemperature	7
2021-08-02 11:00:00	HorizIrrad	632
2021-08-02 12:00:00	EnvTemperature	10
2021-08-02 12:00:00	HorizIrrad	884

【参考方案1】：

使用函数jsonb_array_elements(jsonb)将所有json数组元素返回为value。

select 
    (value->>'time')::timestamp as "time",
    (value->'fieldSet'->>'EnvTemperature')::numeric as "EnvTemperature",
    (value->'fieldSet'->>'HorizIrrad')::numeric as "HorizIrrad"
from the_data
cross join jsonb_array_elements(json_col->'values')

在Db<>fiddle.中测试它

阅读JSON Functions and Operators.