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Add a Root Node to JSON Output with the ROOT Option

  • บทความ

Applies to: SQL Server 2016 (13.x) and later versions Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics (serverless SQL pool only) SQL analytics endpoint in Microsoft Fabric Warehouse in Microsoft Fabric

To add a single, top-level element to the JSON output of the FOR JSON clause, specify the ROOT option.

If you don't specify the ROOT option, the JSON output doesn't include a root element.

Examples

The following table shows the output of the FOR JSON clause with and without the ROOT option.

The examples in the following table assume that the optional RootName argument is empty. If you provide a name for the root element, this value replaces the value root in the examples.

Without the ROOT option:

{  
   <<json properties>>  
}  

[  
   <<json array elements>>  
]

With the ROOT option:

{   
  "root": {  
   <<json properties>>  
 }  
}  

{   
  "root": [  
   << json array elements >>  
  ]  
}

Here's another example of a FOR JSON clause with the ROOT option. This example specifies a value for the optional RootName argument.

Query

SELECT TOP 5   
       BusinessEntityID As Id,  
       FirstName, LastName,  
       Title As 'Info.Title',  
       MiddleName As 'Info.MiddleName'  
   FROM Person.Person  
   FOR JSON PATH, ROOT('info')

Result

{
    "info": [{
        "Id": 1,
        "FirstName": "Ken",
        "LastName": "Sánchez",
        "Info": {
            "MiddleName": "J"
        }
    }, {
        "Id": 2,
        "FirstName": "Terri",
        "LastName": "Duffy",
        "Info": {
            "MiddleName": "Lee"
        }
    }, {
        "Id": 3,
        "FirstName": "Roberto",
        "LastName": "Tamburello"
    }, {
        "Id": 4,
        "FirstName": "Rob",
        "LastName": "Walters"
    }, {
        "Id": 5,
        "FirstName": "Gail",
        "LastName": "Erickson",
        "Info": {
            "Title": "Ms.",
            "MiddleName": "A"
        }
    }]
}

Result (without root)

[{
    "Id": 1,
    "FirstName": "Ken",
    "LastName": "Sánchez",
    "Info": {
        "MiddleName": "J"
    }
}, {
    "Id": 2,
    "FirstName": "Terri",
    "LastName": "Duffy",
    "Info": {
        "MiddleName": "Lee"
    }
}, {
    "Id": 3,
    "FirstName": "Roberto",
    "LastName": "Tamburello"
}, {
    "Id": 4,
    "FirstName": "Rob",
    "LastName": "Walters"
}, {
    "Id": 5,
    "FirstName": "Gail",
    "LastName": "Erickson",
    "Info": {
        "Title": "Ms.",
        "MiddleName": "A"
    }
}]

Learn more about JSON in the SQL Database Engine

For a visual introduction to the built-in JSON support, see the following videos:

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