Skip to content

how-for-json-escapes-special-characters-and-control-characters-sql-server.md

Latest commit

 

History

History
90 lines (71 loc) · 3.32 KB

how-for-json-escapes-special-characters-and-control-characters-sql-server.md

File metadata and controls

90 lines (71 loc) · 3.32 KB
title How FOR JSON escapes special characters and control characters
ms.date 03/16/2017
ms.prod sql
ms.reviewer genemi
ms.technology
ms.topic conceptual
helpviewer_keywords
FOR JSON, special characters
ms.assetid 4ba90025-5a09-4f0a-836a-54c886324530
author jovanpop-msft
ms.author jovanpop
ms.custom seo-dt-2019
monikerRange =azuresqldb-current||>=sql-server-2016||=sqlallproducts-allversions||>=sql-server-linux-2017||=azuresqldb-mi-current

How FOR JSON escapes special characters and control characters (SQL Server)

[!INCLUDEappliesto-ss-asdb-xxxx-xxx-md]

This topic describes how the FOR JSON clause of a SQL Server SELECT statement escapes special characters and represents control characters in the JSON output.

Important

This page describes the built-in support for JSON in Microsoft SQL Server. For general info about escaping and encoding in JSON, see Section 2.5 of the JSON RFC - https://www.ietf.org/rfc/rfc4627.txt.

Escaping of special characters

If the source data contains special characters, the FOR JSON clause escapes them in the JSON output with \, as shown in the following table. This escaping occurs both in the names of properties and in their values.

Special character Escaped output
Quotation mark (") \"
Backslash (\) \|
Slash (/) \/
Backspace \b
Form feed \f
New line \n
Carriage return \r
Horizontal tab \t

Control characters

If the source data contains control characters, the FOR JSON clause encodes them in the JSON output in \u<code> format, as shown in the following table.

Control character Encoded output
CHAR(0) \u0000
CHAR(1) \u0001
... ...
CHAR(31) \u001f

Example

Here's an example of the FOR JSON output for source data that includes both special characters and control characters.

Query:

SELECT  
  'VALUE\    /  
  "' as [KEY\/"],  
  CHAR(0) as '0',  
  CHAR(1) as '1',  
  CHAR(31) as '31'  
FOR JSON PATH

Result:

{
	"KEY\\\t\/\"": "VALUE\\\t\/\r\n\"",
	"0": "\u0000",
	"1": "\u0001",
	"31": "\u001f"
}

Learn more about JSON in SQL Server and Azure SQL Database

Microsoft videos

For a visual introduction to the built-in JSON support in SQL Server and Azure SQL Database, see the following videos:

See Also

Format Query Results as JSON with FOR JSON (SQL Server)
FOR Clause