SQL Server 2019

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select *
into report
from (values
         (1, convert(datetime, '2021-04-29 09:31:10.100'), 10  ),
         (1, convert(datetime, '2021-04-29 09:35:25.800'), 15  ),
         (1, convert(datetime, '2021-04-29 09:36:30.550'), 5   ),
         (2, convert(datetime, '2021-04-29 09:38:15.009'), 100 )
     ) v(user_id, timestamp, balance)
4 rows affected

select user_id,
       max(case when seqnum = 1 then balance end) as opening,
       max(case when seqnum_desc = 1 then balance end) as closing,
       sum(case when seqnum = 1 and seqnum_desc = 1 then 0
                when seqnum = 1 then - balance
                when seqnum_desc = 1 then balance
           end) as movement
from (select r.*,
             row_number() over (partition by user_id order by timestamp) as seqnum,
             row_number() over (partition by user_id order by timestamp desc) as seqnum_desc
      from report r
     ) r
group by user_id;


user_id
opening
closing
movement


1
10
5
-5

2
100
100
0


Warning: Null value is eliminated by an aggregate or other SET operation.


select distinct user_id,
       first_value(balance) over (partition by user_id order by timestamp) as opening,
       first_value(balance) over (partition by user_id order by timestamp desc) as closing,
       (first_value(balance) over (partition by user_id order by timestamp desc) -
        first_value(balance) over (partition by user_id order by timestamp)
       ) as movement
from report r


user_id
opening
closing
movement


1
10
5
-5

2
100
100
0