Migrate data to or from columns using Always Encrypted with SQL Server Import and Export Wizard

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance

The SQL Server Import and Export Wizard is a tool that allows you to copy data from a source to a destination. This document describes how to use the SQL Server Import and Export Wizard if a source and/or a destination is a SQL Server database containing columns protected with Always Encrypted.

Migration scenarios

With the SQL Server Import and Export Wizard, you can implement the following scenarios for migrating data to or from encrypted columns.

Encrypt plaintext data on migration

If your data source contains plaintext data and your destination is a SQL Server database containing encrypted columns, you can use the SQL Server Import and Export Wizard to retrieve the plaintext data from the source, encrypt it and copy the encrypted data (ciphertext) to the encrypted columns in the destination database. For this migration scenario, the data source can be any data store the SQL Server Import and Export Wizard supports. For example, a file, a SQL Server database, or a database in another database system.

To ensure the SQL Server Import and Export Wizard can encrypt data, you need to enable Always Encrypted for the destination database connection and you need to have access to the keys protecting the data in the destination database columns. For more information, see Enable and disable Always Encrypted for a database connection and Permissions for encrypting or decrypting data during migration.

Decrypt encrypted data on migration

If you are migrating data stored in encrypted database columns in a SQL Server database, you can configure the SQL Server Import and Export Wizard to decrypt the data and copy the decrypted (plaintext) data to a destination, which can be any data store the SQL Server Import and Export Wizard supports, for example a file, a SQL Server database or a database in another database system.

To ensure the SQL Server Import and Export Wizard can decrypt data, you need to enable Always Encrypted for the source database connection and you need to have access to the keys protecting the data in the source database columns. For more information, see Enable and disable Always Encrypted for a database connection and Permissions for encrypting or decrypting data during migration.

Re-encrypt data on migration

If you are copying the data from encrypted columns in a source SQL Server database to encrypted columns in the same or another SQL Server database, you can configure the SQL Server Import and Export Wizard to decrypt the data after retrieving it from the source and re-encrypt it before inserting into the encrypted columns in the destination database. Use this method if the schema of the target columns (for example, column data types, encryption types and column encryption keys) are different than the schema of the source columns.

To ensure the SQL Server Import and Export Wizard can encrypt and decrypt data, you need to enable Always Encrypted for both the source database connection and the destination database connection, and you need to have access to the keys protecting the data in both the source and the target database columns. For more information, see Enable and disable Always Encrypted for a database connection and Permissions for encrypting or decrypting data during migration.

Keep data encrypted during migration

If you are copying the data from encrypted columns in a source SQL Server database to encrypted columns in the same or another SQL Server database, and the target columns use exactly the schema (including the same data types, encryption types, and column encryption keys) as the source columns, you can configure the SQL Server Import and Export Wizard to retrieve ciphertext from the source columns and insert the encrypted data (ciphertext) into encrypted column in the target SQL Server database.

For this scenario, you can use any data provider that supports SQL Server to connect to the source or the destination SQL Server database. If you are using a provider that supports Always Encrypted to connect to the destination database, you need to make sure Always Encrypted is disabled for the database connection. For more information, see Enable and disable Always Encrypted for a database connection.

You also need to ensure the database principal (user) the SQL Server Import and Export Wizard uses to connect to the destination database is configured with the ALLOW_ENCRYPTED_VALUE_MODIFICATIONS option set to ON. This option suppresses cryptographic metadata checks on the server in bulk copy operations, which enables the wizard to bulk insert the encrypted data to the destination database without decrypting the data. For more information, see Bulk Load Encrypted Data to Columns Protected by Always Encrypted.

Enable and disable Always Encrypted for a database connection

If your migration scenario requires the SQL Server Import and Export Wizard be able to encrypt and/or decrypt data, you need to configure the source SQL Server database connection and/or the destination SQL Server database connection using a data provider that supports Always Encrypted. You also need to enable Always Encrypted for the source and/or destination database connection.

You can use any data provider for a connection if you do not need the wizard to encrypt or decrypt data on that connection.

The following data providers in the SQL Server Import and Export Wizard support Always Encrypted.

Permissions for encrypting or decrypting data during migration

To encrypt or decrypt data stored in a SQL Server source or destination database, you need the VIEW ANY COLUMN MASTER KEY DEFINITION and VIEW ANY COLUMN ENCRYPTION KEY DEFINITION permissions in the source database. You also need key store permissions to access and use your column master key. For detailed information on key store permissions required for key management operations, go to Create and store column master keys for Always Encrypted and find a section relevant for your key store.

Next steps

See also