Brian Carrig shows how to create certificates from binary:
Sometimes it is necessary to copy a certificate from one database to another database. The most common method I have seen to do this is involves taking a backup of the certificate to disk from one database and then restoring the certificate to the other database.
There is however, a lesser known alternative option available, provided you are working with SQL Server 2012 and above. Sadly despite it being 2017, this is not as foregone a conclusion for SQL Server DBAs as it should be. This alternate option is known as CREATE CERTIFICATE FROM BINARY. There are a few caveats with this option. Chief among them is that you cannot use a variable for the binary value, so you will likely end up needing to use some dynamic SQL.
One of the nice aspects to this feature from an administration and a security perspective is that you do not need to worry about accidentally leaving a copy of your certificate on a disk somewhere or having to remember to delete it after you have imported it into your user database.
Read on to see it in action. Also, it’s about time that Brian started blogging.