For an instructor lead, in-depth look at learning SQL click below.
In this era of digitization, safeguarding sensitive data is of utmost importance. When it comes to SQL servers, data encryption is one of the primary defenses against data breach threats. SQL Server provides a number of ways to encrypt your data. In this blog, we’ll cover some of the fundamental concepts of SQL server data encryption and provide examples using SQL code.
Encryption in SQL: An Overview
The purpose of encryption is to transform data in order to conceal its contents. In SQL Server, there are two main types of encryption: symmetric and asymmetric. Symmetric encryption uses a single key to both encrypt and decrypt data. Asymmetric encryption, on the other hand, uses a pair of keys: one for encryption and one for decryption.
Symmetric Key Encryption
Let’s dive right into how you would use symmetric encryption:
|
1 2 3 4 5 6 |
--Create a Symmetric Key CREATE SYMMETRIC KEY TestKey WITH ALGORITHM = AES_256 ENCRYPTION BY PASSWORD = 'ComplexPassword'; |
In this example, we created a symmetric key using the AES_256 encryption algorithm. The key is encrypted using a password. It’s important to safeguard this password because anyone who knows this password can decrypt the data.
Asymmetric Key Encryption
Now let’s look at the process of creating an asymmetric key and encrypting data using it:
|
1 2 3 4 5 6 |
--Create Asymmetric Key CREATE ASYMMETRIC KEY TestKeyPair WITH ALGORITHM = RSA_2048 ENCRYPTION BY PASSWORD = 'ComplexPassword'; |
In this code snippet, we have created an asymmetric key pair using the RSA_2048 encryption algorithm. Like the symmetric key, this key pair is also protected by a password.
Encrypting and Decrypting Data
Here’s a simple example of how you use these keys to encrypt and decrypt data:
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 |
-- Open the symmetric key with which to encrypt the data. OPEN SYMMETRIC KEY TestKey DECRYPTION BY PASSWORD = 'ComplexPassword'; -- Encrypt the data using the open key. DECLARE @encrypted_varbinary varbinary(8000); SET @encrypted_varbinary = EncryptByKey(Key_GUID('TestKey'), 'Sensitive Data'); -- Close the key CLOSE SYMMETRIC KEY TestKey; -- Open key for decryption OPEN SYMMETRIC KEY TestKey DECRYPTION BY PASSWORD = 'ComplexPassword'; -- Decrypt the data DECLARE @decrypted_varchar nvarchar(4000); SET @decrypted_varchar = DecryptByKey(@encrypted_varbinary); -- Close the key CLOSE SYMMETRIC KEY TestKey; |
Taking a look at these code snippets, you can start to see how SQL Server operates in terms of data encryption. To ensure optimal levels of data security, it’s important to make encryption a central element of your SQL server operations.
Conclusion
SQL Server offers a multitude of features for data encryption, which helps protect your sensitive information from unauthorized access. By using encryption options effectively, you can secure your data and application, ensuring that you are taking a robust approach to data security in your SQL Server databases.