ENCRYPTBYCERT (Transact-SQL)
Encrypts data with the public key of a certificate.
Syntax
EncryptByCert ( certificate_ID , { 'cleartext' | @cleartext } )
Arguments
certificate_ID
The ID of a certificate in the database. int.cleartext
A string of data that will be encrypted with the certificate.@cleartext
A variable of type nvarchar, char, varchar, binary, varbinary, or nchar containing data that will be encrypted with the public key of the certificate.
Return Types
varbinary with a maximum size of 8,000 bytes.
Remarks
This function encrypts data with the public key of a certificate. The ciphertext can only be decrypted with the corresponding private key. Such asymmetric transformations are very costly compared to encryption and decryption using a symmetric key. Asymmetric encryption is therefore not recommended when working with large datasets such as user data in tables.
Examples
This example encrypts the plaintext stored in @cleartext with the certificate called JanainaCert02. The encrypted data is inserted into table ProtectedData04.
INSERT INTO [AdventureWorks2008R2].[ProtectedData04]
values( N'data encrypted by certificate ''Shipping04''',
EncryptByCert(Cert_ID('JanainaCert02'), @cleartext) );
GO