This is one of them little options that I see which quite often gets little consideration or gets set to a user database without consideration of what the consequences may be if that DB becomes unavailable. There are going to be situations where setting a default other than master is essential and there are going to be situations where leaving as master suits best and this comes down to the individual requirements of each login, Recently I had to fix an issue with user connectivity for a single login, the user was getting failed connections when trying to connect to the SQL server when trying to access one of their legacy databases , everything appeared fine – User account was enabled the password hadn’t been changed and was therefore correct, the database they were trying to access was up and accessible but the SQL error log highlighted the real issue.
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