sql 行转列并更改列名(实际应用并截图)

这里是一个实际应用的例子，一开始的数据是错综复杂的，如下图所示，实际很多月份很多的类型，需要的是得到每个部门不同了类型不同月份的实际金额，这儿就用到了行转列的写法，百度了一下确实有效，成功之后的显示字段确实1，2，3，4....这种的，最好变为january,february...的这种所以就用了声明并赋值加case when 的写法顺便吧null的值变为0；在此做下记录，希望也可以帮到用到的人。

下图的sql是这样子的：（这是一个union al l联立的多个表）

 select year(ExpenseDate) as NowYear,ExpenseDept,AccountMonth,ISNULL(AccountMoney,0) as monthmoney,'差旅费' as FYType FROM  CW_WY_TravelExpenseBill_M m  inner join  BPMDB..BPMInstTasks s on m.TaskID = s.TaskID where (s.State='Approved' or s.State='Running')
     union all
     select  year(ExpenseDate)as NowYear,ExpenseDept,AccountMonth,ISNULL(AccountMoney,0) as monthmoney,'日常费用' as FYType FROM  CW_WY_DailyLiveExpenseBill_M m  inner join  BPMDB..BPMInstTasks s on m.TaskID = s.TaskID where (s.State='Approved' or s.State='Running')
     union all
     select NowYear,deptname,NowMonth,ISNULL(PayMoney,0) as monthmoney,FeiYongType as FYType   from CW_WY_DailyLiveExpenseFuKuan_T m inner join  BPMDB..BPMInstTasks s on m.TaskID = s.TaskID where (s.State='Approved' or s.State='Running')

要形成下图这样的效果sql需要有所改动：

SELECT NowYear,ExpenseDept,FYType,January=case when [1]  is null then 0 else [1] end,February=case when [2] is null then 0 else [2] end,March=case when [3] is null then 0 else [3] end,April=case when [4] is null then 0 else [4] end,May=case when [5] is null then 0 else [5] end,June=case when [6] is null then 0 else [6] end,July=case when [7] is null then 0 else [7] end,August=case when [8] is null then 0 else [8] end,September=case when [9] is null then 0 else [9] end,  Octorber=case when [10] is  null then 0 else [10] end,November=case when [11] is null then 0 else [11] end,December=case when [12] is null then 0 else [12] end  FROM (
     select year(ExpenseDate) as NowYear,ExpenseDept,AccountMonth,ISNULL(AccountMoney,0) as monthmoney,'差旅费' as FYType FROM  CW_WY_TravelExpenseBill_M m  inner join  BPMDB..BPMInstTasks s on m.TaskID = s.TaskID where (s.State='Approved' or s.State='Running')
     union all
     select  year(ExpenseDate)as NowYear,ExpenseDept,AccountMonth,ISNULL(AccountMoney,0) as monthmoney,'日常费用' as FYType FROM  CW_WY_DailyLiveExpenseBill_M m  inner join  BPMDB..BPMInstTasks s on m.TaskID = s.TaskID where (s.State='Approved' or s.State='Running')
     union all
     select NowYear,deptname,NowMonth,ISNULL(PayMoney,0) as monthmoney,FeiYongType as FYType   from CW_WY_DailyLiveExpenseFuKuan_T m inner join  BPMDB..BPMInstTasks s on m.TaskID = s.TaskID where (s.State='Approved' or s.State='Running')
 ) /*数据源*/
AS P
PIVOT 
(
    SUM(monthmoney/*行转列后 列的值*/) FOR 
    p.AccountMonth/*需要行转列的列*/ IN ([1],[2],[3],[4],[5],[6],[7],[8],[9],[10],[11],[12]/*列的值*/)
) AS T

主要是两个知识点：行转列的写法和case when 的用法。仅为借鉴，如有错误请指教。