I need a query that return values from the beginning of the current month until today.
For example :
WHERE OrderDate BETWEEN #1/6/2016# AND Now();
If you have a given date, you could use the
DATESERIAL() function to grab the first day of a given month :
SELECT * FROM Orders WHERE OrderDate BETWEEN DATESERIAL(Year(YourDate), Month(YourDate), 1) AND NOW()
If you were able to explicitly pass in the month and year, you could do that as well :
WHERE OrderDate BETWEEN DATESERIAL(2016, 6, 1) AND NOW()