MySQL 8.0

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create table horror (
  id int, 
  groupId int, 
  data varchar(20)
);

insert into horror values
(1, 2, 'apple'), 
(2, 5, 'cinnemon'), 
(3, 5, 'bacon'), 
(4, 5, 'pickles'), 
(5, 5, 'wonka'), 
(6, 42, 'bar'), 
(7, 42, 'linux'), 
(8, 69, 'rocks'), 
(9, 69, 'joe'), 
(10, 69, 'bob'), 
(11, 101, 'briggs'), 
(12, 101, 'kinky_horror');

Records: 12  Duplicates: 0  Warnings: 0


select min(id) as first_id
from horror
group by groupId


first_id


1

2

6

8

11


select h.*
from horror h
inner join (
  select min(id) as first_id
  from horror
  group by groupId
) as s on s.first_id = h.id


id
groupId
data


1
2
apple

2
5
cinnemon

6
42
bar

8
69
rocks

11
101
briggs


select max(id) as last_id
from horror
group by groupId


last_id


1

5

7

10

12


select h.*
from horror h
inner join (
  select max(id) as last_id
  from horror
  group by groupId
) as s on s.last_id = h.id


id
groupId
data


1
2
apple

5
5
wonka

7
42
linux

10
69
bob

12
101
kinky_horror