title | description | author | ms.author | ms.date | ms.service | ms.subservice | ms.topic | ms.custom | helpviewer_keywords | monikerRange | ||||
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Replicate encrypted columns (SSMS) |
Learn how to replicate data in encrypted columns using SQL Server Management Studio (SSMS). |
MashaMSFT |
mathoma |
09/25/2024 |
sql |
replication |
how-to |
|
|
=azuresqldb-mi-current||>=sql-server-2016 |
[!INCLUDEsql-asdbmi] Replication enables you to publish encrypted column data. To decrypt and use this data at the Subscriber, the key that was used to encrypt the data at the Publisher must also be present on the Subscriber. Replication does not provide a secure mechanism to transport encryption keys. You must manually re-create the encryption key at the Subscriber. This topic shows you how to encrypt a column at the Publisher and make sure that the encryption key is available at the Subscriber.
The basic steps are as follows:
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Create the symmetric key at the Publisher.
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Encrypt column data with the symmetric key.
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Publish the table with the encrypted column.
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Subscribe to the publication.
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Initialize the subscription.
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Recreate the symmetric key at the Subscriber using same values for ALGORITHM, KEY_SOURCE, and IDENTITY_VALUE as in step 1.
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Access the encrypted column data.
Note
You should use a symmetric key to encrypt column data. The symmetric key itself can be secured by different means at the Publisher and Subscriber.
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At the Publisher, execute CREATE SYMMETRIC KEY.
[!IMPORTANT]
The value of KEY_SOURCE is valuable data that can be used to re-create the symmetric key and decrypt data. KEY_SOURCE must always be stored and transported securely. -
Execute OPEN SYMMETRIC KEY to open the new key.
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Use the EncryptByKey function to encrypt column data at the Publisher.
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Execute CLOSE SYMMETRIC KEY to close the key.
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Publish the table that contains the encrypted column. For more information, see Create a Publication.
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Subscribe to the publication. For more information, see Create a Pull Subscription or Create a Push Subscription.
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Initialize the subscription. For more information, see Create and Apply the Initial Snapshot.
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At the Subscriber, execute CREATE SYMMETRIC KEY using the same values for ALGORITHM, KEY_SOURCE, and IDENTITY_VALUE as in step 1. You can specify a different value for ENCRYPTION BY.
[!IMPORTANT]
The value of KEY_SOURCE is valuable data that can be used to re-create the symmetric key and decrypt data. KEY_SOURCE must always be stored and transported securely. -
Execute OPEN SYMMETRIC KEY to open the new key.
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Use the DecryptByKey function to decrypt replicated data at the Subscriber.
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Execute CLOSE SYMMETRIC KEY to close the key.
This example creates a symmetric key, a certificate that is used to help secure the symmetric key, and a master key. These keys are created in the publication database. They are then used to create an encrypted column (EncryptedCreditCardApprovalCode) in the SalesOrderHeader
table. This column is published in the AdvWorksSalesOrdersMerge publication instead of the unencrypted CreditCardApprovalCode column. When possible, prompt users to enter security credentials at runtime. If you must store credentials in a script file, you must secure the file to prevent unauthorized access.
:::code language="sql" source="../codesnippet/tsql/replicate-data-in-encryp_1.sql":::
:::code language="sql" source="../codesnippet/tsql/replicate-data-in-encryp_2.sql":::
This example recreates the same symmetric key in the subscription database using the same values for ALGORITHM, KEY_SOURCE, and IDENTITY_VALUE from the first example. This example assumes that you have already initialized a subscription to the AdvWorksSalesOrdersMerge publication to replicate the encrypted column. When possible, prompt users to enter security credentials at runtime. If you must store credentials in a script file, you must secure the file during storage and transport to prevent unauthorized access.
:::code language="sql" source="../codesnippet/tsql/replicate-data-in-encryp_3.sql":::