SQL Server HashBytes

Question

Can you unhash a value that you have stored in the DB?

So if I generate and store a value like this

SELECT HashBytes('MD5', 'HelloWorld')

Can I use a function to unhash it so that I can get the original value backout?

Thanks,

S

Answer 1

Unfortunately not. If you are trying to check if a password or pass phrase is correct, you would only be able to encrypt what you've received, and then compare the two results. If they differ, then obviously the wrong information has been passed in.

Answer 2

No. Cryptographic hashes are by definition one way.