SQLite 3.27

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CREATE TABLE tblData(Id INT, ComputerName TEXT, TimestampOrigin TEXT, Timestamp TEXT, Number INT);
INSERT INTO tblData VALUES 
(1, "Computer1", '2021-02-10 12:00:00', '2021-02-27 12:00:00', 35),
(2, "Computer2", '2021-02-10 12:00:00', '2021-02-27 12:00:00', 24),
(3, "Computer3", '2021-02-09 12:00:00', '2021-02-26 12:00:00', 23),
(3, "Computer4", '2021-02-09 12:00:00', '2021-02-26 12:00:00', null),
(4, "Computer5", '2021-02-08 12:00:00', '2021-02-25 12:00:00', 7),
(5, "Computer6", '2021-02-08 12:00:00', '2021-02-25 12:00:00', 0),
(7, "Computer7", '2021-02-07 12:00:00', '2021-02-24 12:00:00', 9);
SELECT * FROM tblData


Id
ComputerName
TimestampOrigin
Timestamp
Number


1
Computer1
2021-02-10 12:00:00
2021-02-27 12:00:00
35

2
Computer2
2021-02-10 12:00:00
2021-02-27 12:00:00
24

3
Computer3
2021-02-09 12:00:00
2021-02-26 12:00:00
23

3
Computer4
2021-02-09 12:00:00
2021-02-26 12:00:00
null

4
Computer5
2021-02-08 12:00:00
2021-02-25 12:00:00
7

5
Computer6
2021-02-08 12:00:00
2021-02-25 12:00:00
0

7
Computer7
2021-02-07 12:00:00
2021-02-24 12:00:00
9


SELECT t1.TimestampOrigin,
       SUM(t2.Number < 1) AS Less1,
       SUM(t2.Number >= 0 AND t2.Number < 10) AS Less10,
       SUM(t2.Number >= 10 AND t2.Number < 25) AS Less25
FROM (SELECT DISTINCT DATE(TimestampOrigin) TimestampOrigin FROM tblData) t1 
INNER JOIN tblData t2
ON DATE(t2.TimestampOrigin) BETWEEN t1.TimestampOrigin AND DATE(t1.TimestampOrigin, '+17 days')
GROUP BY t1.TimestampOrigin 
ORDER BY t1.TimestampOrigin DESC


TimestampOrigin
Less1
Less10
Less25


2021-02-10
0
0
1

2021-02-09
0
0
2

2021-02-08
1
2
2

2021-02-07
1
3
2

Id	ComputerName	TimestampOrigin	Timestamp	Number
1	Computer1	2021-02-10 12:00:00	2021-02-27 12:00:00	35
2	Computer2	2021-02-10 12:00:00	2021-02-27 12:00:00	24
3	Computer3	2021-02-09 12:00:00	2021-02-26 12:00:00	23
3	Computer4	2021-02-09 12:00:00	2021-02-26 12:00:00	null
4	Computer5	2021-02-08 12:00:00	2021-02-25 12:00:00	7
5	Computer6	2021-02-08 12:00:00	2021-02-25 12:00:00	0
7	Computer7	2021-02-07 12:00:00	2021-02-24 12:00:00	9