SQL Server 2019

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CREATE TABLE ApplicationCandidateCTE
    (ApplicationID int, CandidateId int, JobId int, Row int)
;
    
INSERT INTO ApplicationCandidateCTE
    (ApplicationID, CandidateId, JobId, Row)
VALUES
    (1, 1, 1, 1),
    (2, 1, 2, 2),
    (3, 1, 3, 3),
    (4, 2, 1, 1),
    (5, 2, 2, 2),
    (6, 2, 5, 3),
    (7, 3, 2, 1),
    (8, 3, 6, 2),
    (9, 3, 3, 3),
    (10, 4, 2, 1),
    (11, 4, 1, 2),
    (12, 4, 6, 3),
    (13, 4, 3, 4),
    (14, 5, 5, 1),
    (15, 5, 1, 2),
    (16, 5, 6, 3),
    (17, 6, 3, 3),
    (18, 7, 6, 1),
    (19, 7, 5, 2),
    (20, 7, 4, 3)
;
20 rows affected

-- Search from concatenated JobId
WITH CTE AS
(
  SELECT TOP 1 *,ROW_NUMBER() OVER(ORDER BY ApplicationID) N,
    CONVERT(varchar(max), CONCAT(',',JobId,',')) Jobs
    FROM ApplicationCandidateCTE
    ORDER BY ApplicationID
  UNION ALL
  SELECT a.*,ROW_NUMBER() OVER(ORDER BY a.ApplicationID),
    CONCAT(Jobs,a.JobId,',') Jobs
    FROM ApplicationCandidateCTE a JOIN CTE b
    ON a.ApplicationID > b.ApplicationID AND
       a.CandidateId > b.CandidateId AND
       CHARINDEX(CONCAT(',',a.JobId,','), b.Jobs)=0 AND
       b.N = 1
)
SELECT * FROM CTE WHERE N = 1;


ApplicationID
CandidateId
JobId
Row
N
Jobs


1
1
1
1
1
,1,

5
2
2
2
1
,1,2,

8
3
6
2
1
,1,2,6,

13
4
3
4
1
,1,2,6,3,

14
5
5
1
1
,1,2,6,3,5,

20
7
4
3
1
,1,2,6,3,5,4,


-- CandidateId is not in ascending order
WITH CTE AS
(
  SELECT TOP 1 *,ROW_NUMBER() OVER(ORDER BY ApplicationID) N,
    CONVERT(varchar(max), CONCAT(',',CandidateId,',')) Candidates,
    CONVERT(varchar(max), CONCAT(',',JobId,',')) Jobs
    FROM ApplicationCandidateCTE
    ORDER BY ApplicationID
  UNION ALL
  SELECT a.*,ROW_NUMBER() OVER(ORDER BY a.ApplicationID),
    CONCAT(Candidates,a.CandidateId,',') Candidates,
    CONCAT(Jobs,a.JobId,',') Jobs
    FROM ApplicationCandidateCTE a JOIN CTE b
    ON a.ApplicationID > b.ApplicationID AND
       CHARINDEX(CONCAT(',',a.CandidateId,','), b.Candidates)=0 AND
       CHARINDEX(CONCAT(',',a.JobId,','), b.Jobs)=0 AND
       b.N = 1
)
SELECT * FROM CTE WHERE N = 1;


ApplicationID
CandidateId
JobId
Row
N
Candidates
Jobs


1
1
1
1
1
,1,
,1,

5
2
2
2
1
,1,2,
,1,2,

8
3
6
2
1
,1,2,3,
,1,2,6,

13
4
3
4
1
,1,2,3,4,
,1,2,6,3,

14
5
5
1
1
,1,2,3,4,5,
,1,2,6,3,5,

20
7
4
3
1
,1,2,3,4,5,7,
,1,2,6,3,5,4,


-- Reduce the scope to search for the next CandidateId
WITH CTE AS
(
  SELECT TOP 1 *,ROW_NUMBER() OVER(ORDER BY ApplicationID) N,
    CONVERT(varchar(max), CONCAT(',',JobId,',')) Jobs
    FROM ApplicationCandidateCTE
    ORDER BY ApplicationID
  UNION ALL
  SELECT a.*,ROW_NUMBER() OVER(ORDER BY a.ApplicationID),
    CONCAT(Jobs,a.JobId,',') Jobs
    FROM ApplicationCandidateCTE a JOIN CTE b
    ON a.ApplicationID > b.ApplicationID AND
       a.CandidateId > b.CandidateId AND
       a.CandidateId < b.CandidateId + 3 AND
       CHARINDEX(CONCAT(',',a.JobId,','), b.Jobs)=0 AND
       b.N = 1
)
SELECT * FROM CTE WHERE N = 1;


ApplicationID
CandidateId
JobId
Row
N
Jobs


1
1
1
1
1
,1,

5
2
2
2
1
,1,2,

8
3
6
2
1
,1,2,6,

13
4
3
4
1
,1,2,6,3,

14
5
5
1
1
,1,2,6,3,5,

20
7
4
3
1
,1,2,6,3,5,4,

ApplicationID	CandidateId	JobId	Row	N	Jobs
1	1	1	1	1	,1,
5	2	2	2	1	,1,2,
8	3	6	2	1	,1,2,6,
13	4	3	4	1	,1,2,6,3,
14	5	5	1	1	,1,2,6,3,5,
20	7	4	3	1	,1,2,6,3,5,4,

ApplicationID	CandidateId	JobId	Row	N	Candidates	Jobs
1	1	1	1	1	,1,	,1,
5	2	2	2	1	,1,2,	,1,2,
8	3	6	2	1	,1,2,3,	,1,2,6,
13	4	3	4	1	,1,2,3,4,	,1,2,6,3,
14	5	5	1	1	,1,2,3,4,5,	,1,2,6,3,5,
20	7	4	3	1	,1,2,3,4,5,7,	,1,2,6,3,5,4,