signbycert-transact-sql.md

title	description	author	ms.author	ms.date	ms.service	ms.subservice	ms.topic	f1_keywords	helpviewer_keywords	dev_langs
SIGNBYCERT (Transact-SQL)	SIGNBYCERT (Transact-SQL)	VanMSFT	vanto	03/06/2017	sql	t-sql	reference	SIGNBYCERT SIGNBYCERT_TSQL	text signing [SQL Server] encryption [SQL Server], certificates certificates [SQL Server], text signing SignByCert function signing text [SQL Server] cryptography [SQL Server], certificates	TSQL

SIGNBYCERT (Transact-SQL)

[!INCLUDE SQL Server Azure SQL Database Azure SQL Managed Instance]

Signs text with a certificate and returns the signature.

:::image type="icon" source="../../includes/media/topic-link-icon.svg" border="false"::: Transact-SQL syntax conventions

Syntax

SignByCert ( certificate_ID , @cleartext [ , 'password' ] )  

Arguments

certificate_ID
Is the ID of a certificate in the current database. certificate_ID is int.

@cleartext
Is a variable of type nvarchar, char, varchar, or nchar that contains data that will be signed.

' password '
Is the password with which the certificate's private key was encrypted. password is nvarchar(128).

Return Types

varbinary with a maximum size of 8,000 bytes.

Remarks

Requires CONTROL permission on the certificate.

Examples

The following example signs the text in @SensitiveData with certificate ABerglundCert07, having first decrypted the certificate with password "pGFD4bb925DGvbd2439587y". It then inserts the cleartext and the signature in table SignedData04.

DECLARE @SensitiveData NVARCHAR(max);  
SET @SensitiveData = N'Saddle Price Points are   
    2, 3, 5, 7, 11, 13, 17, 19, 23, 29';  
INSERT INTO [SignedData04]  
    VALUES( N'data signed by certificate ''ABerglundCert07''',  
    @SensitiveData, SignByCert( Cert_Id( 'ABerglundCert07' ),   
    @SensitiveData, N'pGFD4bb925DGvbd2439587y' ));  
GO  

See Also

VERIFYSIGNEDBYCERT (Transact-SQL)
CERT_ID (Transact-SQL)
CREATE CERTIFICATE (Transact-SQL)
ALTER CERTIFICATE (Transact-SQL)
DROP CERTIFICATE (Transact-SQL)
Encryption Hierarchy