SQL Server – Change Database State

--Make Database Read Only

USE​​ [master]

GO

ALTER​​ DATABASE​​ [TESTDB]​​ SET​​ READ_ONLY​​ WITH​​ NO_WAIT

GO

--Make Database Read/Write

USE​​ [master]

GO

ALTER​​ DATABASE​​ [TESTDB]​​ SET​​ READ_WRITE​​ WITH​​ NO_WAIT

GO

--If you face error that if database is already in use, you can resolve the same by making database in single user mode

--1. Set the database to single mode:

ALTER​​ DATABASE​​ [TESTDB]​​ SET​​ SINGLE_USER​​ WITH​​ ROLLBACK​​ IMMEDIATE;

--2. Set the database to Multi-user mode

ALTER​​ DATABASE​​ [TESTDB]

SET​​ MULTI_USER​​ WITH​​ ROLLBACK​​ IMMEDIATE