考虑以下SQL语句:
DECLARE @CustomerId INT = 48;
DECLARE @CurrentYear INT = DATEPART(YEAR, GETDATE());
SELECT
YEAR(o.OrderDate) AS Year,
0 AS Month,
SUM(o.GrandTotal) AS GrandTotal
FROM [Order] o
WHERE
o.CustomerId = @CustomerId AND
o.OrderTypeId = 4 AND
o.IsVoid = 0 AND
YEAR(o.OrderDate) BETWEEN @CurrentYear - 2 AND @CurrentYear
GROUP BY
YEAR(o.OrderDate)
正确产生结果:
2012, 0, 89.00
2011, 0, 230.00
2010, 0, 450.0
但是,如果另一位客户仅在2011年下订单,我需要生成其他2行(尽管有0个值):
2011, 0, 230.00
2012, 0, 0
2010, 0, 0
我怎么想正确地?请注意,报告将在过去3年内生成。
第4次更新 我按照建议修改了代码:
DECLARE @CustomerId INT = 48;
DECLARE @CurrentYear INT = YEAR(GETDATE());
DECLARE @years TABLE (
yr INT
);
INSERT INTO @years VALUES
(@CurrentYear),
(@CurrentYear - 1),
(@CurrentYear - 2)
这会产生如下结果集(我已经检查过并确保是这种情况)。
2012
2011
2010
然后我按如下方式加入表格(RIGHT JOIN):
SELECT
y.yr AS Year,
0 AS Month,
SUM(ISNULL(o.GrandTotal, 0)) AS GrandTotal
FROM [Order] o
RIGHT JOIN @years y ON y.yr = YEAR(o.OrderDate)
WHERE
o.CustomerId = @CustomerId AND
o.OrderTypeId = 4 AND
o.IsVoid = 0
GROUP BY
y.yr
但是,考虑到客户尚未下订单,因此,需要生成3行ZERO值。但是,这些解决方案都没有提到这一点。
最终更新[求助]: where子句阻止这些行位于最终结果集中。所以,正如Darvin建议的那样,我只是用AND替换了WHERE子句,问题就消失了。
SELECT
y.yr AS Year,
0 AS Month,
SUM(ISNULL(o.GrandTotal, 0)) AS GrandTotal
FROM [Order] o
RIGHT JOIN @years y ON y.yr = YEAR(o.OrderDate) AND
o.CustomerId = @CustomerId AND
o.OrderTypeId = 4 AND
o.IsVoid = 0
GROUP BY
y.yr
答案 0 :(得分:1)
我在小提琴中编写了示例代码。 http://sqlfiddle.com/#!3/eddfe/9/0希望它有所帮助。
这个想法是你创建了一个包含所有年份的UDF,然后对该表进行外连接。
答案 1 :(得分:0)
以下内容如何:
DECLARE @CustomerId INT = 48;
DECLARE @CurrentYear INT = DATEPART(YEAR, GETDATE());
;with years as
(
SELECT YEAR(GETDATE()) as yr
UNION ALL SELECT YEAR(DATEADD(YY,-1,GETDATE()))
UNION ALL SELECT YEAR(DATEADD(YY,-2,GETDATE()))
)
SELECT
years.yr
,0 AS Month
,SUM(ISNULL(o.GrandTotal,0)) AS GrandTotal
FROM years
LEFT OUTER JOIN Order o
ON YEAR(o.OrderDate) = years.yr
AND o.customerid = @customerid
AND o.OrderTypeId = 4
AND o.IsVoid = 0
GROUP BY
years.yr