SQL Server 2019

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create table #data (header int, eventid int, eventdate datetime)

insert into #data 
values
('62252595',    '22',   '5/23/2021  12:34:02 PM'),
('62252595',    '81',   '5/23/2021  12:34:03 PM'),
('62252595',    '29',   '5/23/2021  12:34:12 PM'),
('62252595',    '40',   '5/23/2021  12:34:27 PM'),
('62252595',    '22',   '5/23/2021  12:35:02 PM'),
('62252595',    '22',   '5/23/2021  12:36:12 PM'),
('62252595',    '37',   '5/23/2021  12:36:36 PM'),
('62252595',    '77',   '5/23/2021  12:37:04 PM'),
('62252595',    '6',    '5/23/2021  12:37:52 PM'),
('63252595',    '39',   '5/23/2021  12:38:01 PM'),
('63252595',    '81',   '5/23/2021  12:38:04 PM'),
('63252595',    '37',   '5/23/2021  12:38:06 PM'),
('63252595',    '21',   '5/23/2021  12:38:09 PM'),
('63252595',    '75',   '5/23/2021  12:38:10 PM'),
('63252595',    '77',   '5/23/2021  12:38:12 PM'),
('64252595',    '29',   '5/23/2021  12:38:15 PM'),
('64252595',    '26',   '5/23/2021  12:38:18 PM'),
('64252595',    '81',   '5/23/2021  12:38:20 PM'),
('64252595',    '40',   '5/23/2021  12:38:21 PM'),
('64252595',    '81',   '5/23/2021  12:38:24 PM'),
('64252595',    '83',   '5/23/2021  12:39:06 PM'),
('64252595',    '77',   '5/23/2021  12:39:07 PM'),
('65252595',    '41',   '5/23/2021  12:39:12 PM'),
('65252595',    '81',   '5/23/2021  12:39:16 PM'),
('65252595',    '37',   '5/23/2021  12:39:20 PM'),
('65252595',    '18',   '5/23/2021  12:39:56 PM'),
('65252595',    '18',   '5/23/2021  12:40:03 PM'),
('65252595',    '77',   '5/23/2021  12:40:15 PM'),
('65252595',    '36',   '5/23/2021  12:40:46 PM'),
('65252595',    '77',   '5/23/2021  12:40:53 PM')

30 rows affected

header	(No column name)
62252595	2021-05-23 12:34:03.000
65252595	2021-05-23 12:39:16.000