SQL Server 2017

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CREATE TABLE UriData
    ([Serial] int, [Channel] varchar(2), [ReadingDate] datetime, [Value] int)
;
    
INSERT INTO UriData
    ([Serial], [Channel], [ReadingDate], [Value])
VALUES 
    (2209, 'm1', '2018/09/21 00:00:00', 20586),
    (2209, 'm1', '2018/09/21 00:15:00', 20588),
    (2209, 'm1', '2018/09/21 00:30:00', 20591),
    (2209, 'm1', '2018/09/21 00:45:00', 20593),
    (2209, 'm1', '2018/09/21 01:00:00', 20596),
    (2209, 'm1', '2018/09/21 01:15:00', 20598),
    (2209, 'm1', '2018/09/21 01:30:00', 20600),
    (2209, 'm1', '2018/09/21 01:45:00', 20602),
    (2209, 'm1', '2018/09/21 02:00:00', 20604),
    (2209, 'm1', '2018/09/21 02:15:00', 20607),
    (2209, 'm1', '2018/09/21 02:30:00', 20609),
    (2209, 'm1', '2018/09/21 02:45:00', 20612),
    (2209, 'm1', '2018/09/20 21:00:00', 20559),
    (2209, 'm1', '2018/09/20 21:15:00', 20561),
    (2209, 'm1', '2018/09/20 21:30:00', 20563),
    (2209, 'm1', '2018/09/20 21:45:00', 20566),
    (2209, 'm1', '2018/09/20 22:00:00', 20568),
    (2209, 'm1', '2018/09/20 22:15:00', 20570),
    (2209, 'm1', '2018/09/20 22:30:00', 20572),
    (2209, 'm1', '2018/09/20 22:45:00', 20575),
    (2209, 'm1', '2018/09/20 23:00:00', 20577),
    (2209, 'm1', '2018/09/20 23:15:00', 20580),
    (2209, 'm1', '2018/09/20 23:30:00', 20582),
    (2209, 'm1', '2018/09/20 23:45:00', 20584),
    (2209, 'm1', '2018/09/20 15:15:00', 20459),
    (2209, 'm1', '2018/09/20 15:30:00', 20467),
    (2209, 'm1', '2018/09/20 16:00:00', 20483),
    (2209, 'm1', '2018/09/20 16:15:00', 20490),
    (2209, 'm1', '2018/09/20 16:30:00', 20497),
    (2209, 'm1', '2018/09/20 16:45:00', 20505),
    (2209, 'm1', '2018/09/20 17:00:00', 20512),
    (2209, 'm1', '2018/09/20 17:15:00', 20520),
    (2209, 'm1', '2018/09/20 17:30:00', 20526),
    (2209, 'm1', '2018/09/20 17:45:00', 20529),
    (2209, 'm1', '2018/09/20 18:00:00', 20531),
    (2209, 'm1', '2018/09/20 18:15:00', 20533),
    (2209, 'm1', '2018/09/20 18:30:00', 20536),
    (2209, 'm1', '2018/09/20 18:45:00', 20538),
    (2209, 'm1', '2018/09/20 19:00:00', 20540),
    (2209, 'm1', '2018/09/20 19:15:00', 20542),
    (2209, 'm1', '2018/09/20 19:30:00', 20545),
    (2209, 'm1', '2018/09/20 19:45:00', 20547),
    (2209, 'm1', '2018/09/20 20:00:00', 20550),
    (2209, 'm1', '2018/09/20 20:15:00', 20552),
    (2209, 'm1', '2018/09/20 20:30:00', 20554),
    (2209, 'm1', '2018/09/20 00:00:00', 20136),
    (2209, 'm1', '2018/09/20 00:15:00', 20138),
    (2209, 'm1', '2018/09/20 00:30:00', 20140),
    (2209, 'm1', '2018/09/20 00:45:00', 20143),
    (2209, 'm1', '2018/09/20 01:00:00', 20145),
    (2209, 'm1', '2018/09/20 01:15:00', 20148),
    (2209, 'm1', '2018/09/20 01:30:00', 20150),
    (2209, 'm1', '2018/09/20 01:45:00', 20152),
    (2209, 'm1', '2018/09/20 02:00:00', 20154),
    (2209, 'm1', '2018/09/20 02:15:00', 20156),
    (2209, 'm1', '2018/09/20 02:30:00', 20158),
    (2209, 'm1', '2018/09/20 02:45:00', 20161),
    (2209, 'm1', '2018/09/20 03:00:00', 20163),
    (2209, 'm1', '2018/09/20 03:15:00', 20166),
    (2209, 'm1', '2018/09/20 03:30:00', 20168),
    (2209, 'm1', '2018/09/20 03:45:00', 20170),
    (2209, 'm1', '2018/09/20 04:00:00', 20172),
    (2209, 'm1', '2018/09/20 04:15:00', 20174),
    (2209, 'm1', '2018/09/20 04:30:00', 20176),
    (2209, 'm1', '2018/09/20 04:45:00', 20179),
    (2209, 'm1', '2018/09/20 05:00:00', 20181),
    (2209, 'm1', '2018/09/20 05:15:00', 20183),
    (2209, 'm1', '2018/09/20 05:30:00', 20186),
    (2209, 'm1', '2018/09/20 05:45:00', 20188),
    (2209, 'm1', '2018/09/20 06:00:00', 20190),
    (2209, 'm1', '2018/09/20 06:15:00', 20192),
    (2209, 'm1', '2018/09/20 06:30:00', 20195),
    (2209, 'm1', '2018/09/20 06:45:00', 20197),
    (2209, 'm1', '2018/09/20 07:00:00', 20199),
    (2209, 'm1', '2018/09/20 07:15:00', 20201),
    (2209, 'm1', '2018/09/20 07:30:00', 20204),
    (2209, 'm1', '2018/09/20 07:45:00', 20206),
    (2209, 'm1', '2018/09/20 08:00:00', 20208),
    (2209, 'm1', '2018/09/20 08:15:00', 20217),
    (2209, 'm1', '2018/09/20 08:30:00', 20226),
    (2209, 'm1', '2018/09/20 08:45:00', 20234),
    (2209, 'm1', '2018/09/20 09:00:00', 20243),
    (2209, 'm1', '2018/09/20 09:15:00', 20251),
    (2209, 'm1', '2018/09/20 09:30:00', 20260),
    (2209, 'm1', '2018/09/20 09:45:00', 20269),
    (2209, 'm1', '2018/09/20 10:00:00', 20277),
    (2209, 'm1', '2018/09/20 10:15:00', 20286),
    (2209, 'm1', '2018/09/20 10:30:00', 20294),
    (2209, 'm1', '2018/09/20 10:45:00', 20303),
    (2209, 'm1', '2018/09/20 11:00:00', 20311),
    (2209, 'm1', '2018/09/20 11:15:00', 20321),
    (2209, 'm1', '2018/09/20 11:30:00', 20329),
    (2209, 'm1', '2018/09/20 11:45:00', 20337),
    (2209, 'm1', '2018/09/20 12:00:00', 20347),
    (2209, 'm1', '2018/09/20 12:15:00', 20355),
    (2209, 'm1', '2018/09/20 12:30:00', 20363),
    (2209, 'm1', '2018/09/20 12:45:00', 20373),
    (2209, 'm1', '2018/09/20 13:00:00', 20381),
    (2209, 'm1', '2018/09/20 13:15:00', 20390),
    (2209, 'm1', '2018/09/20 13:30:00', 20399),
    (2209, 'm1', '2018/09/20 13:45:00', 20408),
    (2209, 'm1', '2018/09/20 14:00:00', 20416),
    (2209, 'm1', '2018/09/20 14:15:00', 20424),
    (2209, 'm1', '2018/09/20 14:30:00', 20433)

DECLARE @_DateFrom DATETIME ='2018-09-20 00:00'
DECLARE @_DateTo DATETIME = '2018-09-21 00:00'

SELECT [Serial], 
	   [Channel],
	   [ReadingDate],
	   [00:15],[00:30],[00:45],[01:00],[01:15],[01:30],[01:45],[02:00],[02:15],[02:30],[02:45],[03:00],
	   [03:15],[03:30],[03:45],[04:00],[04:15],[04:30],[04:45],[05:00],[05:15],[05:30],[05:45],[06:00],
	   [06:15],[06:30],[06:45],[07:00],[07:15],[07:30],[07:45],[08:00],[08:15],[08:30],[08:45],[09:00],
	   [09:15],[09:30],[09:45],[10:00],[10:15],[10:30],[10:45],[11:00],[11:15],[11:30],[11:45],[12:00],
	   [12:15],[12:30],[12:45],[13:00],[13:15],[13:30],[13:45],[14:00],[14:15],[14:30],[14:45],[15:00],
	   [15:15],[15:30],[15:45],[16:00],[16:15],[16:30],[16:45],[17:00],[17:15],[17:30],[17:45],[18:00],
	   [18:15],[18:30],[18:45],[19:00],[19:15],[19:30],[19:45],[20:00],[20:15],[20:30],[20:45],[21:00],
	   [21:15],[21:30],[21:45],[22:00],[22:15],[22:30],[22:45],[23:00],[23:15],[23:30],[23:45],[00:00]
FROM(
    SELECT 
        Serial AS [Serial],
        Channel AS [Channel],
        (CASE WHEN CAST(ReadingDate AS DATE) > CAST(@_DateFrom AS DATE) 
            THEN CAST(@_DateFrom AS DATE) 
            ELSE CAST(ReadingDate AS DATE)
         END)  AS [ReadingDate],
        CAST(ReadingDate AS TIME) AS [ReadingTime],
        Value AS [Value]
    FROM UriData
     WHERE ReadingDate > @_DateFrom  AND ReadingDate <= @_DateTo  AND Serial = '2209'   
    ) AS [Raw]
PIVOT
(
    MAX( [Value] ) FOR [ReadingTime] IN( [00:15],[00:30],[00:45],[01:00],[01:15],[01:30],[01:45],[02:00],
	                                     [02:15],[02:30],[02:45],[03:00],[03:15],[03:30],[03:45],[04:00],
										 [04:15],[04:30],[04:45],[05:00],[05:15],[05:30],[05:45],[06:00],
										 [06:15],[06:30],[06:45],[07:00],[07:15],[07:30],[07:45],[08:00],
										 [08:15],[08:30],[08:45],[09:00],[09:15],[09:30],[09:45],[10:00],
										 [10:15],[10:30],[10:45],[11:00],[11:15],[11:30],[11:45],[12:00],
										 [12:15],[12:30],[12:45],[13:00],[13:15],[13:30],[13:45],[14:00],
										 [14:15],[14:30],[14:45],[15:00],[15:15],[15:30],[15:45],[16:00],
										 [16:15],[16:30],[16:45],[17:00],[17:15],[17:30],[17:45],[18:00],
										 [18:15],[18:30],[18:45],[19:00],[19:15],[19:30],[19:45],[20:00],
									     [20:15],[20:30],[20:45],[21:00],[21:15],[21:30],[21:45],[22:00],
										 [22:15],[22:30],[22:45],[23:00],[23:15],[23:30],[23:45],[00:00])
) AS pvt
ORDER BY ReadingDate DESC, Channel, [Serial]

Serial	Channel	ReadingDate	00:15	00:30	00:45	01:00	01:15	01:30	01:45	02:00	02:15	02:30	02:45	03:00	03:15	03:30	03:45	04:00	04:15	04:30	04:45	05:00	05:15	05:30	05:45	06:00	06:15	06:30	06:45	07:00	07:15	07:30	07:45	08:00	08:15	08:30	08:45	09:00	09:15	09:30	09:45	10:00	10:15	10:30	10:45	11:00	11:15	11:30	11:45	12:00	12:15	12:30	12:45	13:00	13:15	13:30	13:45	14:00	14:15	14:30	14:45	15:00	15:15	15:30	15:45	16:00	16:15	16:30	16:45	17:00	17:15	17:30	17:45	18:00	18:15	18:30	18:45	19:00	19:15	19:30	19:45	20:00	20:15	20:30	20:45	21:00	21:15	21:30	21:45	22:00	22:15	22:30	22:45	23:00	23:15	23:30	23:45	00:00
2209	m1	20/09/2018 00:00:00	20138	20140	20143	20145	20148	20150	20152	20154	20156	20158	20161	20163	20166	20168	20170	20172	20174	20176	20179	20181	20183	20186	20188	20190	20192	20195	20197	20199	20201	20204	20206	20208	20217	20226	20234	20243	20251	20260	20269	20277	20286	20294	20303	20311	20321	20329	20337	20347	20355	20363	20373	20381	20390	20399	20408	20416	20424	20433	null	null	20459	20467	null	20483	20490	20497	20505	20512	20520	20526	20529	20531	20533	20536	20538	20540	20542	20545	20547	20550	20552	20554	null	20559	20561	20563	20566	20568	20570	20572	20575	20577	20580	20582	20584	20586