Sometimes when you add a Database Query monitoring (under BizTalk Environment), the expected value is not returned or empty. The CurrentStatus column is Red. In some cases the Dashboard shows green for this monitor.
In these cases, please verify if the below conditions are true
The query you have entered should only return a scalar value (int, string or bool) at all the times. Verity this by running your query on SQL Server Management Console.
If its a scalar query, verify that IIS AppPool user where BizTalk360 site is running has READ access to the database you are trying to monitor
Also verify that IIS AppPool user and BizTalk360 Monitor service user (Services.msc) are same or have the same access rights to the database you are trying to monitor. (Dashboard view is generated by monitor service and the expected value column's value is generated by UI code in AppPool)
Make sure your scalar query returns the results under 10 seconds. There is a hard timeout of 10 seconds set.