備份的數據庫首次還原後可能出現打不開的情況，需執行以下

--------------------忘記密碼了 刪除掉----------------
DROP SYMMETRIC KEY[SymmetricKeyCert]

DROP CERTIFICATE [CertRSA]

drop master key

-------------------- 重新創建 -------------------------
–創建Master KEY
CREATE MASTER KEY ENCRYPTION BY PASSWORD= N’NewPassword’;

–創建證書
CREATE CERTIFICATE [CertRSACertRSA]
AUTHORIZATION [dbo]
WITH SUBJECT = N’Certificate’, START_DATE = N’1/12/2015 00:00:00’, EXPIRY_DATE = N’12/31/2050 00:00:00’
ACTIVE FOR BEGIN_DIALOG = ON;

–創建祕鑰
CREATE SYMMETRIC KEY [ymmetricKeyCert]
AUTHORIZATION [dbo]
WITH ALGORITHM = AES_256
ENCRYPTION BY CERTIFICATE [CertRSACertRSA]

-------------備份的數據庫還原後可能出現打不開的情況，需執行以下-------------

–用密碼打開Database master key
OPEN MASTER KEY DECRYPTION BY PASSWORD=N’NewPassword’

–向服務器提供DMK （使用服務主祕鑰 （SMK）加密），以後就可以自動解密了

ALTER MASTER KEY REGENERATE WITH ENCRYPTION BY PASSWORD =N’NewPassword’