Steps to install Service pack in Production environments:

1. First of all raise a change order and get the necessary approvals for the downtime window. Normally it takes around 45-60 minutes to install Service pack if there are no issues.

2. Once the downtime window is started, take a full backup of the user databases and system databases including the Resource database.

3. List down all the Startup parameters, Memory Usage, CPU Usage etc and save it in a separate file.

4. Install the service pack on SQL Servers.

5. Verify all the SQL Services are up and running as expected.

6. Validate the application functionality.

Note: There is a different approach to install Service pack on SQL Server cluster instances. That will be covered in SQL Server cluster.