Use of DATEADD function to get various Dates

Get First day of current week: SELECT DATEADD(wk, DATEDIFF(wk, 0, GETDATE()-1), 0) Get Last day of current week: SELECT DATEADD(wk, DATEDIFF(wk, 0, GETDATE()),6) Get First day of current month: SELECT DATEADD(mm,DATEDIFF(mm,0,GETDATE()),0) Get Last day of current month: SELECT DATEADD(mm,DATEDIFF(mm,0,GETDATE())+1,-1) Get First day of current quarter: SELECT DATEADD(qq, DATEDIFF(qq, 0, GETDATE()), …