我仔细阅读了许多示例,并加入了几个示例,以得出以下结论;
DECLARE @StartDate SMALLDATETIME, @EndDate SMALLDATETIME;
SELECT @StartDate = '20170930', @EndDate = '20180930';
;WITH d(d) AS
(
SELECT DATEADD(MONTH, n, DATEADD(MONTH, DATEDIFF(MONTH, 0, @StartDate), 0))
FROM ( SELECT TOP (DATEDIFF(MONTH, @StartDate, @EndDate) + 1)
n = ROW_NUMBER() OVER (ORDER BY [object_id]) - 1
FROM sys.all_objects ORDER BY [object_id] ) AS n
)
SELECT
[Period] = CONVERT(VARCHAR(4), YEAR(d.d)) + '-' + CONVERT(VARCHAR(2), MONTH(d.d)),
QtyTotal = ISNULL(SUM(o.QEXIT),0)
FROM d LEFT OUTER JOIN VE_STOCKTRANS AS o
ON o.TRANSDATE >= d.d
AND o.TRANSDATE < DATEADD(MONTH, 1, d.d)
WHERE STOCKID = 6000 AND TRANSTYPE = 3553
GROUP BY d.d
ORDER BY d.d;
我需要获取过去一年中某商品的总销售质量。如果该商品在该特定月份没有任何销售,则该月旁边应显示0。除非提供WHERE子句,否则上述查询会执行所需的操作。添加WHERE子句以获取特定产品的数据后,没有销售的月份消失了。
如果有经验的SQL开发人员可以向我显示正确的方向,我将不胜感激。
谢谢
答案 0 :(得分:1)
您需要将条件移至ON
:
-- ...
SELECT
[Period] = CONVERT(VARCHAR(4),YEAR(d.d)) +'-'+ CONVERT(VARCHAR(2), MONTH(d.d)),
QtyTotal = ISNULL(SUM(o.QEXIT),0)
FROM d LEFT OUTER JOIN VE_STOCKTRANS AS o
ON o.TRANSDATE >= d.d
AND o.TRANSDATE < DATEADD(MONTH, 1, d.d)
AND STOCKID = 6000 AND TRANSTYPE = 3553 -- here
GROUP BY d.d
ORDER BY d.d;
答案 1 :(得分:0)
一种更通用的方法是在加入之前应用过滤器。
;WITH d(d) AS
(
SELECT DATEADD(MONTH, n, DATEADD(MONTH, DATEDIFF(MONTH, 0, @StartDate), 0))
FROM ( SELECT TOP (DATEDIFF(MONTH, @StartDate, @EndDate) + 1)
n = ROW_NUMBER() OVER (ORDER BY [object_id]) - 1
FROM sys.all_objects ORDER BY [object_id] ) AS n
),
o AS
(
SELECT *
FROM VE_STOCKTRANS
WHERE STOCKID = 6000
AND TRANSTYPE = 3553
)
SELECT
[Period] = CONVERT(VARCHAR(4), YEAR(d.d)) + '-' + CONVERT(VARCHAR(2), MONTH(d.d)),
QtyTotal = ISNULL(SUM(o.QEXIT),0)
FROM
d
LEFT OUTER JOIN
o
ON o.TRANSDATE >= d.d
AND o.TRANSDATE < DATEADD(MONTH, 1, d.d)
GROUP BY
d.d
ORDER BY
d.d;
正如您在另一个答案中所看到的,这里并非严格必要。但是,在执行FULL OUTER JOIN
或其他复杂查询时,将您的源过滤到一个作用域并加入一个单独的作用域将非常有帮助。
(我总是过滤源,我讨厌块状番茄酱。)