Question

有数据范围的用户数据 data

我正在尝试使用查询更新标记部分。如果相同的用户ID组重叠任何一天的范围，则应在标记部分中重叠。

您能否告诉我如何标记这些重叠数据感谢

Text file format:

ID UserID   registereddate  termdate    flag
1   abcd    1/1/2018    2/28/2018   overlapping with 2
2   abcd    1/1/2018    6/30/2018   overlapping with 1
3   abcd    8/1/2018    12/31/2018  
4   bbbb    5/1/2018    6/30/2018   overlapping with 5
5   bbbb    6/1/2018    7/30/2018   overlapping with 4
6   bbbb    9/1/2018    9/30/2018   
7   bbbb    10/1/2018   10/30/2018  
8   bbbb    11/1/2018   11/30/2018  
9   ccccc   7/1/2018    9/30/2018   overlapping with 10
10  ccccc   9/1/2018    12/31/2018  overlapping with 9
11  dddd    8/1/2018    8/31/2018   
12  dddd    12/1/2018   12/31/2018  
13  eeee    9/1/2018    12/31/2018  overlapping with 17
14  eeee    8/1/2018    8/31/2018   
15  eeee    9/1/2018    9/30/2018   overlapping with 15

Answer 1

要获取'overlapping'，请使用exists：

select t.*,
       (case when exists (select 1
                          from t t2
                          where t2.registereddate < t.termdate and
                                t2.termdate > t.registereddate
                         )
             then 'overlaps'
        end)
from t;

在更新中，这看起来像：

update t
    set flag = 'overlaps'
    where exists (select 1
                  from t t2
                  where t2.registereddate < t.termdate and
                        t2.termdate > t.registereddate
                 );

在SQL Server中获取字符串字段中的重叠记录列表要复杂得多。获得成对的重叠列表非常简单。

Answer 2

您也可以将表格内部连接到自身并比较日期

SELECT * 
FROM [Table] t1
INNER JOIN [Table] t2 
ON  t1.ID <> t2.ID
AND t1.UserId = t2.UserId
AND ((t1.RegisterDate BETWEEN t2.RegisterDate AND t2.TermDate) OR (t1.TermDate BETWEEN t2.RegisterDate AND t2.TermDate))

虽然越多的字段越来越复杂，但这就变成了

请参阅此DBFiddle

如何从相同的表中找到重叠的日期范围（多个重叠）

2 个答案: