Question

我已经在下面创建了函数ParseJson：

    create function ParseJson(
    @json nvarchar(max))
returns @tempTable table (topKey nvarchar(max), [Key] nvarchar(max), [Value] nvarchar(max))
as
begin

    insert 
        @tempTable
    select 
        x.[key] topKey
        , y.[key] 
        , y.[value] 
    from openjson(@json) x
    cross apply openjson(x.[value]) y

    return

end

-- execute
select * from ParseJson(@json)

我定义了一个变量@json，它不是数组字符串：

set @json = 
N'{
  "Chapter":
  {
      "Section":"1.1"
      , "Title":"Hello world."
  }
}'

然后我执行查询，我将得到结果：

如果我重置变量@json，它是一个数组字符串：

declare @json nvarchar(max)
set @json = 
N'{
  "Chapter":[
        {
            "Section":"1.1"
            , "Title":"Hello world."
        }
        ,
        {
            "Section":"1.2"
            , "Title":"Be happy."
        }       
    ]
}'

然后我执行查询，我将得到结果：

我希望我能得到以下结果：

我不知道我期望的结果是否合理？

如何调整功能以满足期望？

Answer 1

如果我正确理解了您的问题，那么下一个陈述是获得结果的一种可能方法。该示例显示了如何获取数组键和值（我添加了附加的Something键）。您需要再添加一个CROSS APPLY。

DECLARE @json nvarchar(max)
SET @json = 
N'{
  "Chapter":[
        {
            "Section":"1.1", 
            "Title":"Hello world.",
            "Something":"Something value"
        }
        ,
        {
            "Section":"1.2", 
            "Title":"Be happy."
        }       
    ]
}'

SELECT 
   x.[key] topKey, 
   z.[key],
   z.[value]
FROM OPENJSON(@json) x
CROSS APPLY (SELECT * FROM OPENJSON(x.[value])) y
CROSS APPLY (SELECT * FROM OPENJSON(y.[value])) z

输出：

topKey  key         value
Chapter Section     1.1
Chapter Title       Hello world.
Chapter Something   Something value
Chapter Section     1.2
Chapter Title       Be happy.

更新：

如果您的JSON具有不同类型的嵌套对象，则方法将有所不同：

DECLARE @json nvarchar(max)
set @json = N'{ 
   "Chapter": [ 
       {
       "Section":"1.1", 
       "Title":"Hello world.", 
       "Something":"Something value"
       }, 
       {
       "Section":"1.2", 
       "Title":"Be happy." 
       }
   ], 
   "Author": { "name":"Annie" , "sex":"Female" } 
}'

SELECT 
   x.[key] topKey,
   z.[key] [Key],
   z.[value] AS [Value]
FROM OPENJSON(@json) x
CROSS APPLY (SELECT * FROM OPENJSON(x.[value])) y
CROSS APPLY (SELECT * FROM OPENJSON(y.[value])) z
WHERE y.[type] = 5
UNION ALL
SELECT 
   x.[key] topKey,
   y.[key] [Key],
   y.[value] AS [Value]
FROM OPENJSON(@json) x
CROSS APPLY (SELECT * FROM OPENJSON(x.[value])) y
WHERE y.[type] <> 5

输出：

topKey  Key         Value
Chapter Section     1.1
Chapter Title       Hello world.
Chapter Something   Something value
Chapter Section     1.2
Chapter Title       Be happy.
Author  name        Annie
Author  sex         Female

如何使用mssql解析JSON数组字符串？

1 个答案: