Question: How can I set and check the isolation level  READ_COMMITTED_SNAPSHOT ? I executed the command and it’s still running after 60 minutes, I’m worried I may have corrupted the database

Answer: You probably haven’t corrupted the database, but the command you’re running is blocked by another active connection.   SQL Server Books Online states that no other connections to the database are allowed while the command is executing.  Although single-user mode is not required.

Use sp_who2 to see who else is connected to the database. Read How to detect and troubleshoot blocking and deadlocks

--to set read_commited_snapshot ON
ALTER DATABASE [MY_DATABASE] SET READ_COMMITTED_SNAPSHOT ON
--to check if read_commited_snapshot is on
select name,is_read_committed_snapshot_on from sys.databases where name = 'MY_DATABASE'

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