Default SQL Server Connection for SSMS

[CamTheLegend]

SQL 2019 - SSMS 19.3.4.0

I was always wrongly under the impression that SSMS required a server connection in the Object Explorer to run a script against.  We have databases with the same names on 2 servers as we're preparing for migration and I accidentally ran a script on server B, even though there appeared to be no connection open to server B.  Only Server A was connected in the object explorer.  I was then shocked to find that any new sql script I opened was connected to server B which had been closed out in Object Explorer.

What controls the default server for a script when opening via File / Open in SSMS?  What is the best way to lock a script to specific server or make it more obvious which server this is being applied to.  I may need to get used to looking in the bottom right where it displays the SQL server, but I'd like to make it more fool proof. 

I see activating SQLCMD Mode on the Query Menu is one option, but I wonder what the downside to this might be such that it is not default behaviour. 

[#2 · Accepted solution]

Hello
Yo cannot lock a session from SSMS. it will always go get the one from previous opened script when you do it via File -> Open

I'll suggest you to use SELECT @@SERVERNAME to double check on which server your are, and also strongly suggest to use BEGIN TRANSACTION with COMMIT / ROLLBACK , especially when you are tunning ad-hoc scripts in production servers. this way you can revert in case of a mistake

[#3]

@Javier_Villegas Thanks for your insights.  I like the @@SERVERNAME idea as a passive solution that I think will help.  I'm also more aware now, so the odds are much lower based on on past experience.  I always use BEGIN TRANSACTION and a --COMMIT that is commented until I check that the update was successful.