Question

我正在尝试创建一个表，根据某行的开始和结束日期计算多个日历。我有一张看起来像这样的表：

键Start_date End_date

123.1 1-10-2009 24-12-2009

123.2 1-7-2010 9-2-2011

123.3 1-5-2011 30-10-2011

.........

对于每个键，我想要一个新行，其中startdate为+1个月，直到enddate。

现在我的查询只有在我的临时表包含一行时才有效：

DECLARE @StartDate DATE = (select Start_date from #dim2);

SET DATEFIRST 7;
SET DATEFORMAT ymd;
SET LANGUAGE US_ENGLISH;

DECLARE @CutoffDate DATE = (select End_date from #dim2);

CREATE TABLE #dim3
([verwachte_aflossing]      DATE,-- PRIMARY KEY,
 );

INSERT #dim3([verwachte_aflossing] )
SELECT d 
FROM
(
 SELECT d = DATEADD(month, rn-1, @StartDate) 
 FROM 
 (
   SELECT TOP (DATEDIFF(month, @StartDate, @CutoffDate)) 
     rn = ROW_NUMBER() OVER (ORDER BY s1.[object_id])
   FROM sys.all_objects AS s1
   CROSS JOIN sys.all_objects AS s2
   ORDER BY s1.[object_id]
 ) AS x
) AS y

现在有人如何处理这个问题？

Answer 1

对于SQL Server递归 cte 是执行此操作的一个选项

WITH CTE as
(
    select [Key], start_date, end_date from table
    union all
    select [Key], dateadd(month,1,start_date) start_date, end_date 
    from cte
    where datediff(month, start_date, end_date) > 0
)

SELECT * FROM CTE
OPTION (MAXRECURSION 0)

SQL - 在一个表中创建多个日历

1 个答案: