如何使用结果集中的2个分组列进行PIVOT？

问题描述

我有一个查询，输出以下内容：

ApptDate    Truck_ID   Item    Qty
'8-19-20'   TruckA     ItemA   100
'8-19-20'   TruckB     ItemA   200
'8-20-20'   TruckC     ItemB   300
'8-20-20'   TruckD     ItemB   400
...
@H_502_5@
我需要PIVOT使其返回以下内容：
Item    Truck_ID    Day1    Day2 ... Day14
ItemA   TruckA      100     0        0
ItemA   TruckB      200     0        0
ItemB   TruckC      0       300      0
ItemB   TruckD      0       400      0
@H_502_5@
我尝试了这个，但是它给出了一个错误：

 Msg 8114，第16级，状态1，第413行
将数据类型nvarchar转换为datetime时出错。
信息473，第16层，州1，第413行
PIVOT运算符中提供了不正确的值“ Day1”。

select
item,truck_id,Day1,Day2,Day3,Day4,Day5,Day6,Day7,Day8,Day9,Day10,Day11,Day12,Day13,Day14 
from(
select

    ds.ApptDate,c.truck_id,c.item,sum(c.qty) qty

from

    maintable c with(nolock)
    inner join secondtable ds with(nolock) on c.truck_id = ds.truckid and ds.type = 'O'

where

    ds.apptdate between cast(getdate() as date) and dateadd(day,14,cast(getdate() as date))
    and coalesce(ds.CancelTruck,0) <> 1
    and ds.Status <> '5'

group by

    c.truck_id,ds.ApptDate

) sourcetable

pivot
(
sum(qty)
for apptdate in ([Day1],[Day2],[Day3],[Day4],[Day5],[Day6],[Day7],[Day8],[Day9],[Day10],[Day11],[Day12],[Day13],[Day14])

) as pivottable
@H_502_5@


解决方法
由于您希望固定的列数，因此我们不一定需要动态SQL。一种选择是使用条件汇总...以及大量重复输入：
select
    item,truck_id,sum(case when appt_date = cast(getdate() as date)                    then qty else 0 end) day0,sum(case when appt_date = dateadd(day,-1,cast(getdate() as date)) then qty else 0 end) day1,-2,cast(getdate() as date)) then qty else 0 end) day2,...
    sum(case when appt_date = dateadd(day,-14,cast(getdate() as date)) then qty else 0 end) day14
from ( -- your current query here --) t
group by item,truck_id
    

      ,
        
此方法在最小日期和AppDate上使用datediff。
;with 
min_dt_cte(min_dt) as (select min(cast(AppDate as date)) from MyTable),pvt_dt_cte(ApptDate,Truck_ID,Item,Qty,DayNum) as (
    select t.*,datediff(d,mdc.min_dt,cast(AppDate as date))
    from min_dt_cte mdc
         cross join
         MyTable t)
select
  pdc.Item,pdc.Truck_ID,iif(pdc.DayNum=1,0) Day1,iif(pdc.DayNum=2,0) Day2,...
  iif(pdc.DayNum=14,0) Day14
from
  pvt_dt_cte pdc;