SQL

Question

假设我们有这些数据

CREATE TABLE [dbo].[tValues]
(
    [cValue] [VARCHAR](50) NULL
) ON [PRIMARY]

INSERT INTO [dbo].[tValues] ([cValue]) 
VALUES ('red'), ('green'), ('blue'), ('brown')

来自这个查询：

SELECT 
    (JSON_QUERY((SELECT 
                     'Ball' AS title, 
                     '20cm' AS size,
                     (SELECT cValue FROM tValues FOR JSON PATH) AS [colors]
                 FOR JSON PATH))) AS product
FOR JSON PATH, WITHOUT_ARRAY_WRAPPER

我得到了这个 JSON 结果：

{
    "product": [
                 { "title":"Ball", 
                   "size":"20cm", 
                   "colors": [
                                { "cValue": "red" },
                                { "cValue": "green" },
                                { "cValue": "blue" },
                                { "cValue": "brown" }
                             ]
                 }
               ]
}

但我需要在 colors 标签中没有列名和大括号，如下所示：

{
    "product": [
                  {
                      "title": "Ball",
                      "size": "20cm",
                      "colors": [ "red", "green", "blue", "brown" ]
                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                  }
               ]
}

我该怎么做？

Answer 1

一种可能的解决方案是使用 for xml path 和 stuff 来构建您的数组：

SELECT 
    (JSON_QUERY((SELECT 
                     'Ball' AS title, 
                     '20cm' AS size,
                      JSON_QUERY(
                    '[' + STUFF(( SELECT ',' + '"' + cValue + '"' 
                    FROM tValues 
                    FOR XML PATH('')),1,1,'') + ']' ) AS [colors]
                 FOR JSON PATH)

                 )) AS product
FOR JSON PATH, WITHOUT_ARRAY_WRAPPER

结果：

{
   "product":[
      {
         "title":"Ball",
         "size":"20cm",
         "colors":[
            "red",
            "green",
            "blue",
            "brown"
         ]
      }
   ]
}

SQL - 生成没有列名的 JSON 数组

SQL - generate JSON array without column names

tsql

json

sql-server-2016