SQL Server 2022

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DECLARE @data TABLE(id int, newgroup bit, idfilter tinyint, idtank tinyint, created datetime, desired_datagroup_result_example int);
INSERT INTO @data VALUES
(3541,0,2,5,'2024-07-01 08:00:01.000',102),(1740,1,1,3,'2024-07-01 08:00:01.000',100),(1739,0,1,3,'2024-07-01 08:00:02.000',100),(3540,0,2,5,'2024-07-01 08:00:02.000',102),(3539,0,2,5,'2024-07-01 08:00:03.000',102),
(1738,0,1,3,'2024-07-01 08:00:03.000',100),(1737,0,1,3,'2024-07-01 08:00:04.000',100),(3538,0,2,5,'2024-07-01 08:00:04.000',102),(3537,0,2,5,'2024-07-01 08:00:05.000',102),(5342,0,2,1,'2024-07-01 09:00:01.000',103),
(5341,0,2,1,'2024-07-01 09:00:02.000',103),(5340,0,2,1,'2024-07-01 09:00:03.000',103),(5339,0,2,1,'2024-07-01 09:00:04.000',103),(5338,0,2,1,'2024-07-01 09:00:05.000',103),(5337,0,2,1,'2024-07-01 09:00:06.000',103),
(5336,0,2,1,'2024-07-01 09:00:07.000',103),(5335,0,2,1,'2024-07-01 09:00:08.000',103),(5334,1,2,1,'2024-07-01 09:16:09.000',104),(5333,0,2,1,'2024-07-01 09:16:10.000',104),(5332,0,2,1,'2024-07-01 09:16:11.000',104),
(5331,0,2,1,'2024-07-01 09:16:12.000',104),(5344,0,2,5,'2024-07-01 10:00:01.000',105),(5343,1,1,3,'2024-07-01 10:00:01.000',101),(5345,0,1,3,'2024-07-01 10:00:02.000',101),(5346,0,2,5,'2024-07-01 10:00:02.000',105),
(5347,0,2,5,'2024-07-01 10:00:03.000',105),(5348,0,1,3,'2024-07-01 10:00:03.000',101),(5349,0,1,3,'2024-07-01 10:00:04.000',101),(5350,0,2,5,'2024-07-01 10:00:04.000',105),(5351,0,2,5,'2024-07-01 10:00:05.000',105),
(5352,0,2,1,'2024-07-01 11:00:01.000',106),(5353,0,2,1,'2024-07-01 11:00:02.000',106),(5354,0,2,1,'2024-07-01 11:00:03.000',106),(5355,0,2,1,'2024-07-01 11:00:04.000',106),(5356,0,2,1,'2024-07-01 11:00:05.000',106),
(5357,0,2,1,'2024-07-01 11:00:06.000',106),(5358,0,2,1,'2024-07-01 11:00:07.000',106),(5359,0,2,1,'2024-07-01 11:00:08.000',106),(5360,1,2,1,'2024-07-01 11:16:09.000',107),(5361,0,2,1,'2024-07-01 11:16:10.000',107),
(5362,0,2,1,'2024-07-01 11:16:11.000',107),(5363,0,2,1,'2024-07-01 11:16:12.000',107);

with cte as
(
  select id, newgroup, idfilter, idtank, created, 
         desired = desired_datagroup_result_example,
         prev_created = lag(created) over (partition by idfilter order by created)
  from   @data
),
cte2 as
(
SELECT *,
       grp = sum( case when datediff(minute, prev_created, created) > 15
                then 1
                else 0
                end) over (partition by idfilter order by created)
FROM   cte
)
select *, datagroup = 99 + dense_rank () over (order by idfilter, grp)
from   cte2
ORDER BY idfilter ASC, created ASC;

id	newgroup	idfilter	idtank	created	desired	prev_created	grp	datagroup
1740	True	1	3	2024-07-01 08:00:01.000	100	null	0	100
1739	False	1	3	2024-07-01 08:00:02.000	100	2024-07-01 08:00:01.000	0	100
1738	False	1	3	2024-07-01 08:00:03.000	100	2024-07-01 08:00:02.000	0	100
1737	False	1	3	2024-07-01 08:00:04.000	100	2024-07-01 08:00:03.000	0	100
5343	True	1	3	2024-07-01 10:00:01.000	101	2024-07-01 08:00:04.000	1	101
5345	False	1	3	2024-07-01 10:00:02.000	101	2024-07-01 10:00:01.000	1	101
5348	False	1	3	2024-07-01 10:00:03.000	101	2024-07-01 10:00:02.000	1	101
5349	False	1	3	2024-07-01 10:00:04.000	101	2024-07-01 10:00:03.000	1	101
3541	False	2	5	2024-07-01 08:00:01.000	102	null	0	102
3540	False	2	5	2024-07-01 08:00:02.000	102	2024-07-01 08:00:01.000	0	102
3539	False	2	5	2024-07-01 08:00:03.000	102	2024-07-01 08:00:02.000	0	102
3538	False	2	5	2024-07-01 08:00:04.000	102	2024-07-01 08:00:03.000	0	102
3537	False	2	5	2024-07-01 08:00:05.000	102	2024-07-01 08:00:04.000	0	102
5342	False	2	1	2024-07-01 09:00:01.000	103	2024-07-01 08:00:05.000	1	103
5341	False	2	1	2024-07-01 09:00:02.000	103	2024-07-01 09:00:01.000	1	103
5340	False	2	1	2024-07-01 09:00:03.000	103	2024-07-01 09:00:02.000	1	103
5339	False	2	1	2024-07-01 09:00:04.000	103	2024-07-01 09:00:03.000	1	103
5338	False	2	1	2024-07-01 09:00:05.000	103	2024-07-01 09:00:04.000	1	103
5337	False	2	1	2024-07-01 09:00:06.000	103	2024-07-01 09:00:05.000	1	103
5336	False	2	1	2024-07-01 09:00:07.000	103	2024-07-01 09:00:06.000	1	103
5335	False	2	1	2024-07-01 09:00:08.000	103	2024-07-01 09:00:07.000	1	103
5334	True	2	1	2024-07-01 09:16:09.000	104	2024-07-01 09:00:08.000	2	104
5333	False	2	1	2024-07-01 09:16:10.000	104	2024-07-01 09:16:09.000	2	104
5332	False	2	1	2024-07-01 09:16:11.000	104	2024-07-01 09:16:10.000	2	104
5331	False	2	1	2024-07-01 09:16:12.000	104	2024-07-01 09:16:11.000	2	104
5344	False	2	5	2024-07-01 10:00:01.000	105	2024-07-01 09:16:12.000	3	105
5346	False	2	5	2024-07-01 10:00:02.000	105	2024-07-01 10:00:01.000	3	105
5347	False	2	5	2024-07-01 10:00:03.000	105	2024-07-01 10:00:02.000	3	105
5350	False	2	5	2024-07-01 10:00:04.000	105	2024-07-01 10:00:03.000	3	105
5351	False	2	5	2024-07-01 10:00:05.000	105	2024-07-01 10:00:04.000	3	105
5352	False	2	1	2024-07-01 11:00:01.000	106	2024-07-01 10:00:05.000	4	106
5353	False	2	1	2024-07-01 11:00:02.000	106	2024-07-01 11:00:01.000	4	106
5354	False	2	1	2024-07-01 11:00:03.000	106	2024-07-01 11:00:02.000	4	106
5355	False	2	1	2024-07-01 11:00:04.000	106	2024-07-01 11:00:03.000	4	106
5356	False	2	1	2024-07-01 11:00:05.000	106	2024-07-01 11:00:04.000	4	106
5357	False	2	1	2024-07-01 11:00:06.000	106	2024-07-01 11:00:05.000	4	106
5358	False	2	1	2024-07-01 11:00:07.000	106	2024-07-01 11:00:06.000	4	106
5359	False	2	1	2024-07-01 11:00:08.000	106	2024-07-01 11:00:07.000	4	106
5360	True	2	1	2024-07-01 11:16:09.000	107	2024-07-01 11:00:08.000	5	107
5361	False	2	1	2024-07-01 11:16:10.000	107	2024-07-01 11:16:09.000	5	107
5362	False	2	1	2024-07-01 11:16:11.000	107	2024-07-01 11:16:10.000	5	107
5363	False	2	1	2024-07-01 11:16:12.000	107	2024-07-01 11:16:11.000	5	107

DECLARE @data2 TABLE(id int, newgroup bit, idfilter tinyint, idtank tinyint, created datetime, desired_datagroup_result_example int, denserank_group varchar(16));
;WITH res AS(
	SELECT	id, newgroup, idfilter, idtank, created, desired_datagroup_result_example,
			--IIF(newgroup=1,dr_newgroup,dr_main-dr_newgroup) AS denserankgroup
			CONVERT(varchar(8),IIF(newgroup=1,criteriafilter_group,criteriafilter_main-criteriafilter_group))+
			CONVERT(varchar(8),IIF(newgroup=1,criteriatank_group,criteriatank_main-criteriatank_group)) AS denserankgroup
	FROM (
		SELECT	*,
--				DENSE_RANK() OVER (PARTITION BY idfilter, idtank ORDER BY idfilter, created ASC) AS dr_main,					-- will generate
--				DENSE_RANK() OVER (PARTITION BY idfilter, idtank, newgroup ORDER BY idfilter, created ASC) AS dr_newgroup,	-- merged islands groups

DENSE_RANK() OVER (PARTITION BY idfilter ORDER BY idfilter, created ASC) AS criteriafilter_main,				-- will also
				DENSE_RANK() OVER (PARTITION BY idfilter, newgroup ORDER BY idfilter, created ASC) AS criteriafilter_group,		-- generate merged 
				DENSE_RANK() OVER (PARTITION BY idtank ORDER BY idfilter, created ASC) AS criteriatank_main,					-- islands when
				DENSE_RANK() OVER (PARTITION BY idtank, newgroup ORDER BY idfilter, created ASC) AS criteriatank_group			-- grouping
		FROM @data
	) AS tmp
)INSERT INTO @data2 SELECT * FROM res;

--SELECT * FROM @data2 ORDER BY idfilter ASC, created ASC;

SELECT MIN(idfilter) AS idfilter, MIN(idtank) AS idtank, MIN(created) AS [start], MAX(created) AS [end]
FROM @data2 GROUP BY desired_datagroup_result_example ORDER BY desired_datagroup_result_example -- for comparison purpose

SELECT idfilter, idtank, MIN(created) AS [start], MAX(created) AS [end]
FROM @data2 GROUP BY idfilter, idtank, denserank_group
ORDER BY idfilter, [start];

idfilter	idtank	start	end
1	3	2024-07-01 08:00:01.000	2024-07-01 08:00:04.000
1	3	2024-07-01 10:00:01.000	2024-07-01 10:00:04.000
2	5	2024-07-01 08:00:01.000	2024-07-01 08:00:05.000
2	1	2024-07-01 09:00:01.000	2024-07-01 09:00:08.000
2	1	2024-07-01 09:16:09.000	2024-07-01 09:16:12.000
2	5	2024-07-01 10:00:01.000	2024-07-01 10:00:05.000
2	1	2024-07-01 11:00:01.000	2024-07-01 11:00:08.000
2	1	2024-07-01 11:16:09.000	2024-07-01 11:16:12.000

idfilter	idtank	start	end
1	3	2024-07-01 08:00:01.000	2024-07-01 08:00:04.000
1	3	2024-07-01 10:00:01.000	2024-07-01 10:00:04.000
2	5	2024-07-01 08:00:01.000	2024-07-01 08:00:05.000
2	1	2024-07-01 09:00:01.000	2024-07-01 09:00:08.000
2	1	2024-07-01 09:16:09.000	2024-07-01 11:00:08.000
2	5	2024-07-01 10:00:01.000	2024-07-01 10:00:05.000
2	1	2024-07-01 11:16:09.000	2024-07-01 11:16:12.000