当存在重复键并且只需要一个时，如何从Json数据中提取不同的键值？

Question

在下面的示例 json 中，我只需要提取 Parameter_1、Parameter_2 等的第二次出现，而不是第一次，任何人都可以帮助我吗

{
  "response" :
  [
    {
      "Parameter_1" : "high",
      "Parameter_2" : 100,
      "Parameter_3" : "",
      "Parameter_4" : null,
      "Parameter_5" : "Pune",
      "address" :
      {
        "address" :
        [
          "India"
        ]
      },
      "addressElements" :
      {
        "Parameter_11" : null,
        "Parameter_12" : "250",
        "Parameter_13" : null,
        "Parameter_14" : null,
        "Parameter_15" : "India",
        "Parameter_16" : "LN",
        "Parameter_17" : null,
        "Parameter_18" : null,
        "Parameter_19" : null,
        "Parameter_20" : null
      }
    },
    {
      "Parameter_1" : "high",
      "Parameter_2" : 100,
      "Parameter_3" : "",
      "Parameter_4" : null,
      "Parameter_5" : "250",
      "address" :
      {
        "address" :
        [
          "India"
        ]
      },
      "addressElements" :
      {
        "Parameter_11" : null,
        "Parameter_12" : "250",
        "Parameter_13" : null,
        "Parameter_14" : null,
        "Parameter_15" : "India",
        "Parameter_16" : "LN",
        "Parameter_17" : null,
        "Parameter_18" : null,
        "Parameter_19" : null,
        "Parameter_20" : null
      }
    }
  ]
}

预期结果集：

{
  "response" :
  [   
    {
      "Parameter_1" : "high",
      "Parameter_2" : 100,
      "Parameter_3" : "",
      "Parameter_4" : null,
      "Parameter_5" : "250",
      "address" :
      {
        "address" :
        [
          "India"
        ]
      },
      "addressElements" :
      {
        "Parameter_11" : null,
        "Parameter_12" : "250",
        "Parameter_13" : null,
        "Parameter_14" : null,
        "Parameter_15" : "India",
        "Parameter_16" : "LN",
        "Parameter_17" : null,
        "Parameter_18" : null,
        "Parameter_19" : null,
        "Parameter_20" : null
      }
    }
  ]
}

Answer 1

为此使用 JSON_TRANSFORM （docs），在您的情况下，KEEP 操作可以解决问题：

with json_doc AS
(SELECT
'{
  "response" :
  [
    {
      "Parameter_1" : "high",
      "Parameter_2" : 100,
      "Parameter_3" : "",
      "Parameter_4" : null,
      "Parameter_5" : "Pune",
      "address" :
      {
        "address" :
        [
          "India"
        ]
      },
      "addressElements" :
      {
        "Parameter_11" : null,
        "Parameter_12" : "250",
        "Parameter_13" : null,
        "Parameter_14" : null,
        "Parameter_15" : "India",
        "Parameter_16" : "LN",
        "Parameter_17" : null,
        "Parameter_18" : null,
        "Parameter_19" : null,
        "Parameter_20" : null
      }
    },
    {
      "Parameter_1" : "high",
      "Parameter_2" : 100,
      "Parameter_3" : "",
      "Parameter_4" : null,
      "Parameter_5" : "250",
      "address" :
      {
        "address" :
        [
          "India"
        ]
      },
      "addressElements" :
      {
        "Parameter_11" : null,
        "Parameter_12" : "250",
        "Parameter_13" : null,
        "Parameter_14" : null,
        "Parameter_15" : "India",
        "Parameter_16" : "LN",
        "Parameter_17" : null,
        "Parameter_18" : null,
        "Parameter_19" : null,
        "Parameter_20" : null
      }
    }
  ]
}' AS json_data FROM dual
)
SELECT JSON_TRANSFORM(json_data, KEEP '$.response[1]' RETURNING CLOB PRETTY ) AS modified_json FROM json_doc

MODIFIED_JSON                                                                   
--------------------------------------------------------------------------------
{
  "response" :
  [
    {
      "Parameter_1" : "high",
      "Parameter_2" : 100,
      "Parameter_3" : "",
      "Parameter_4" : null,
      "Parameter_5" : "250",
      "address" :
      {
        "address" :
        [
          "India"
        ]
      },
      "addressElements" :
      {
        "Parameter_11" : null,
        "Parameter_12" : "250",
        "Parameter_13" : null,
        "Parameter_14" : null,
        "Parameter_15" : "India",
        "Parameter_16" : "LN",
        "Parameter_17" : null,
        "Parameter_18" : null,
        "Parameter_19" : null,
        "Parameter_20" : null
      }
    }
  ]
}