MySQL 8.0

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select version();


version()


8.0.23


create table logs (log_id int);
insert into logs values (1), (2), (4), (5), (6), (8), (10), (12), (23), (24);
select start_id, min(end_id) as end_id
from (
    select t1.log_id as start_id
    from logs as t1
    left join logs as t2
        on t1.log_id-1 = t2.log_id
    where t2.log_id is null
) tt_start
join (
    select t1.log_id as end_id
    from logs as t1
    left join logs as t2
        on t1.log_id+1 = t2.log_id
    where t2.log_id is null
) tt_end
where start_id<=end_id
group by start_id;


start_id
end_id


1
2

4
6

8
8

10
10

12
12

23
24


select min(log_id), max(log_id)
from
(
  select log_id, log_id - row_number() over (order by log_id) as grp
  from logs
) grouped
group by grp
order by grp;


min(log_id)
max(log_id)


1
2

4
6

8
8

10
10

12
12

23
24