What is sp_configure commands and set commands?

Use sp_configure to display or change server-level settings. To change database-level settings, use ALTER DATABASE. To change settings that affect only the current user session, use the SET statement.

What command do we use to rename a db?

sp_renamedb 'oldname' , 'newname'

What is the difference between a local and a global variable?

A local temporary table exists only for the duration of a connection or, if defined inside a compound statement, for the duration of the compound statement.
A global temporary table remains in the database permanently, but the rows exist only within a given connection. When connection are closed, the data in the global temporary table disappears. However, the table definition remains with the database for access when database is opened next time.

What is log shipping?

Log shipping is the process of automating the backup of database and transaction log files on a production SQL server, and then restoring them onto a standby server. Enterprise Editions only supports log shipping. In log shipping the transactional log file from one server is automatically updated into the backup database on the other server. If one server fails, the other server will have the same db can be used this as the Disaster Recovery plan. The key feature of log shipping is that is will automatically backup transaction logs throughout the day and automatically restore them on the standby server at defined interval.

What is Raiseerror?

Stored procedures report errors to client applications via the RAISERROR command. RAISERROR
doesn't change the flow of a procedure; it merely displays an error message, sets the @@ERROR
automatic variable, and optionally writes the message to the SQL Server error log and the NT
application event log.