最近24个月的数据

Question

我想显示24个月的数据(按月名称(，但如查询所示，我必须每月放置24列，这会使我的查询长时间。<<<<<</p>

DECLARE @sql NVARCHAR(MAX) = 'SELECT [STORE] = ET_LIBELLE,
CONVERT(DECIMAL(15,0),SUM(CASE WHEN YEAR(GP_DATEPIECE) = YEAR(DATEADD(MONTH,-1,GETDATE()))
AND  month(GP_DATEPIECE) =  MONTH( DATEADD(MONTH,-1,GETDATE()))
THEN ISNULL([SALES], 0) ELSE 0 END)) AS ' + DATENAME(MONTH, DATEADD(MM,-1, GETDATE())) + ',
CONVERT(DECIMAL(15,0),SUM(CASE WHEN YEAR(GP_DATEPIECE) = YEAR(DATEADD(MONTH,-2,GETDATE()))
AND  month(GP_DATEPIECE) =  MONTH( DATEADD(MONTH,-2,GETDATE()))
THEN ISNULL([SALES], 0) ELSE 0 END)) AS ' + DATENAME(MONTH, DATEADD(MM,-2, GETDATE())) + ',
.
.
.
FROM PIECE
GROUP BY ET_LIBELLE'
EXEC sp_executesql @sql

结果：

STORE   -   April   -   March   -   February   -   ..
--------------------------------------------------------
S1      -   5500    -   6530    -    4550      -   ..
S2      -   2400    -   8740    -    9650      -   ..
..
--------------------------------------------------------

是否有任何解决方案可以优化并使我的查询快速？

Answer 1

此以下脚本将在12个月(1月至12月(之前返回数据，但每年1行。如果可以接受，则可以使用此查询。您还可以设置一个月的编号(@howmanymonth = n(，以选择要选择数据的月数。

DECLARE @HowManyMonth INT
SET @HowManyMonth = 24
DECLARE @StartDate DATE
SET @StartDate = CAST(DATEADD(DD,-(DAY(DATEADD(MM,-(@HowManyMonth-1),GETDATE()))-1),DATEADD(MM,-(@HowManyMonth-1),GETDATE())) AS DATE)
SELECT * FROM
(
    SELECT Store,Sales,
    YEAR(GP_DATEPIECE) YR,
    CASE  MONTH(GP_DATEPIECE)
        WHEN 1 THEN 'JAN' WHEN 2 THEN 'FEB' WHEN 3 THEN 'MAR' WHEN 4 THEN 'APR' WHEN 5 THEN 'MAY' WHEN 6 THEN 'JUN'
        WHEN 7 THEN 'JUL'   WHEN 8 THEN 'AUG' WHEN 9 THEN 'SEP' WHEN 10 THEN 'OCT' WHEN 11 THEN 'NOV' WHEN 12 THEN 'DEC'
    END MONTH
    FROM PIECE
    WHERE GP_DATEPIECE >= @StartDate
)AS P
PIVOT
(
    SUM(Sales) 
    FOR MONTH IN ([JAN],[FEB],[MAR],[APR],[MAY],[JUN],[JUL],[AUG],[SEP],[OCT],[NOV],[DEC])
) PVT