Question

以下是我要解决的问题。我有一个表，我存储StartExclusionDate和EndExclusionDate并为我的对象设置ApplyDate（称为排除）。表中可以有许多ExtId条目。

我想从上一个连续记录中获取ApplyDate，其中StartExclusionDate和EndExclusionDate之间包含传递给查询的日期。

所以这是我在SQL 2005中创建的表：

Id int PK
ExtId int FK
StartExclusionDate datetime null
EndExclusionDate datetime null
ApplyDate not null

这是一个示例数据集：

  ID  |  ExtID  |  StartDate  |  EndDate  |  ApplyDate
--------------------------------------------------------
   1      101     11/15/2005    3/15/2010   11/15/2005
   2      101                               12/30/2005
   3      101       1/1/2000     1/1/2000     1/1/2006
   4      101       4/1/2008                  4/1/2008
   5      101                    8/1/2010     6/1/2008
   6      101      11/1/2006   12/31/2010    11/1/2009

我将传递2个参数，@ ExtId和@dtDate。我想根据以下条件检索的记录：@ExtId = 101, @dtDate = '6/15/2008'将 ID = 4

逻辑是：

获取ExtId = 101的所有记录以及ApplyDate＆lt; ='6/15/2008'的位置，对ApplyDate DESC进行排序
如果第一条记录的开始日期和结束日期介于'6/15/2008'之间，请通过查看下一条记录找到最初设置排除的记录

我想在没有CURSOR的情况下找到一种方法，是否可以使用查询或CTE？

修改这里用光标

完成

IF OBJECT_ID('TempDB..#t_edr','U') IS NOT NULL
  DROP TABLE #t_edr

CREATE TABLE #t_edr
(
    Id INT NOT NULL,
    ExtId INT NOT NULL,
    StartDate DATETIME NULL,
    EndDate DATETIME NULL,
    ApplyDate DATETIME NOT NULL
)

DECLARE @ExtID INT, @dtDate DATETIME, @dtReturn DATETIME
SELECT @ExtID = 101, @dtDate = '6/15/2008'  

SET NOCOUNT ON
INSERT INTO #t_edr VALUES (1, 101, '11/15/2005', '3/15/2010', '11/15/2005')
INSERT INTO #t_edr VALUES (2, 101, NULL, NULL, '12/30/2005')
INSERT INTO #t_edr VALUES (3, 101, '1/1/2000', '1/1/2000', '1/1/2006')
INSERT INTO #t_edr VALUES (4, 101, '4/1/2008', NULL, '4/1/2008')
INSERT INTO #t_edr VALUES (5, 101, NULL, '8/1/2010', '6/1/2008')
INSERT INTO #t_edr VALUES (6, 101, '11/1/2006', '12/31/2010', '6/1/2009')
SET NOCOUNT OFF

IF EXISTS (
    SELECT EDR.ID FROM #t_edr EDR
    INNER JOIN (SELECT TOP 1 ID FROM #t_edr WHERE ExtId = @ExtID AND ApplyDate <= @dtDate ORDER BY ApplyDate DESC) LatestEDR
    ON EDR.ID = LatestEDR.ID
    WHERE ExtId = @ExtID 
    AND ApplyDate <= @dtDate    
    AND (StartDate IS NULL OR StartDate <= @dtDate)
    AND (EndDate IS NULL OR EndDate >= @dtDate)
    )
    BEGIN
        DECLARE @ID INT, @StartEDR DATETIME, @EndEDR DATETIME, @ApplyDate DATETIME, 
            @CurrentApplyDate DATETIME, @Continue BIT

        DECLARE c CURSOR LOCAL FAST_FORWARD FOR     
        SELECT Id, StartDate, EndDate, ApplyDate FROM #t_edr 
        WHERE ExtId = @ExtID AND ApplyDate <= @dtDate ORDER BY ApplyDate DESC

        OPEN c

        FETCH NEXT FROM c INTO @id, @startedr, @endedr, @ApplyDate
        IF @@FETCH_STATUS <> 0 SET @Continue = 0
        ELSE SET @Continue = 1

        SET @CurrentApplyDate = @ApplyDate
        WHILE @Continue = 1
        BEGIN                                   
            IF @StartEDR >= @dtDate OR @EndEDR <= @dtDate
                SET @Continue = 0

            IF @Continue = 1
            BEGIN
                SET @CurrentApplyDate = @ApplyDate  
                FETCH NEXT FROM c INTO @id, @startedr, @endedr, @ApplyDate
                IF @@FETCH_STATUS <> 0 SET @Continue = 0
            END
        END
        CLOSE c
        DEALLOCATE c

        SELECT @CurrentApplyDate
    END 
ELSE
    PRINT 'NOT EXCLUDED'

DROP TABLE #t_edr

Answer 1

select top 1 * from table
where ApplyDate <= '4/15/2008'
and (startdate is null or startdate<= '4/15/2008')
and (enddate is null or enddate >= '4/15/2008')
and extid = '101'
order by  ApplyDate desc

SQL查询查找单个，已排序的记录

1 个答案: