A.[订单日期]–[发货日期]B.[发货日期]–[订单日期]C.DATEDIFF(‘week’,[订单日期],[发货日期])D.DATEPART(‘week’,[订单日期],[发货日期])
A.if null then zerB.if nullC.ZND.SN
A.COUNT([订单金额])B.COUNTD([订单金额])C.SUM([订单金额])D.AVG([订单金额])