select cast(CONVERT(char(10), getdate(), 110) as datetime) [today]
, datename(dw, getdate()) [day]
, datepart(dw, getdate()-1) [day of week]
, datepart(dw, getdate()-1)-1 [days since monday]
, 7-datepart(dw, getdate()-1) [days until sunday]
, cast(CONVERT(char(10), (getdate()-(datepart(dw, getdate()-1)-1)), 110) as datetime) [monday]
, cast(CONVERT(char(10), (getdate()+(7-datepart(dw, getdate()-1))), 110) as datetime) [sunday]
query utile quando si devono trattare le settimane...