ALTER DATABASE failed because a lock could not be placed on database
After you get the error, run
EXEC sp_who2Look for the database in the list. It's possible that a connection was not terminated. If you find any connections to the database, run
KILL <SPID>where <SPID> is the SPID for the sessions that are connected to the database.
Try your script after all connections to the database are removed.
Unfortunately, I don't have a reason why you're seeing the problem, but here is a link that shows that the problem has occurred elsewhere.
I managed to reproduce this error by doing the following.
Connection 1 (leave running for a couple of minutes)
CREATE DATABASE TESTING123GOUSE TESTING123;SELECT NEWID() AS X INTO FOOFROM sys.objects s1,sys.objects s2,sys.objects s3,sys.objects s4 ,sys.objects s5 ,sys.objects s6Connections 2 and 3
set lock_timeout 5;ALTER DATABASE TESTING123 SET SINGLE_USER WITH ROLLBACK IMMEDIATE;
Try this if it is "in transition" ...
http://learnmysql.blogspot.com/2012/05/database-is-in-transition-try-statement.html
USE masterGOALTER DATABASE <db_name>SET OFFLINE WITH ROLLBACK IMMEDIATE......ALTER DATABASE <db_name> SET ONLINE