You cannot modify the permissions of the SA user, but you can disable and enable user SA with ALTER LOGIN. Log in with Windows authentication first.
SQL SERVER – Change Collation of Database Column – T-SQL Script
How to change collation of database column with ALTER TABLE ALTER COLUMN and COLLATE, then check it in sys.columns. A short test script shows each step.
Designing a Database for Multiple Customers
A database for multiple customers can share tables, split schemas, or split databases; the choice balances isolation and operating cost.
Keeping Personal Data Out of Test Databases
Keeping personal data out of test databases requires synthetic records or masking during refresh, plus verification before access.
Encrypting Connections to SQL Server
Encrypting connections to SQL Server requires a trusted certificate, careful Force Encryption rollout, and tests with real drivers.
SQL SERVER – Fix : Error : Login failed for user ‘UserName’. The user is not associated with a trusted SQL Server connection
Login failed, not associated with a trusted SQL Server connection? I hit it between SQL Server 2008 and 2005 and fixed it with a matching Windows user.
SQL SERVER – Stored Procedure WITH ENCRYPTION and Execution Plan
Here is what I found about WITH ENCRYPTION and execution plan: an encrypted SP hides its actual execution plan too. Two sample SPs show it.