Msg 40636 Cannot use reserved database master.
Applies to: SQL Azure Database V12.
After upgrading a SQL Azure Database server to V12 you run the following
statement and notice the master database does not have compatibility level 130.
SELECT [name], compatibility_level
WHERE [name] =
You then try to set the compatibility level of master database using the
ALTER DATABASE [Master]
SET COMPATIBILITY_LEVEL = 130;
but you receive below error message:
Msg 40636, Level 16, State 1, Line 1
Cannot use reserved database name 'Master' in this operation.
The compatibility level of 100 on the master database of the SQL Azure server is
expected as mentioned on SQL Azure documentation:
"Databases created before mid-June 2016 will not be affected, and will maintain
their current compatibility level (100, 110, or 120). Databases that migrated
from Azure SQL Database version V11 to V12 will have a compatibility level of
either 100 or 110. "
The compatibility level of master database cannot be changed on SQL Azure since
it is considered a reserved database.
To this day, we don't know of any benefit from running master database on
compatibility 130 instead of 120 or 100.