FYzbAMPm

1drop table if exists  owners cascade;
2create table owners(
3    id bigint primary key generated always as identity ,
4    name text not null
5)
6;
7
8insert into owners(name)
9select random()::text from generate_series(1,20000);
10--insert 200,000 owners records 
11     
12delete  from owners
13where id %10 = 0; 
14     
15drop table if exists cats;
16create table cats(
17    id serial primary key ,
18    name varchar(20000) not null,
19    owner_id int not null references owners(id)
20);
21
22--insert 1bn cats records
23insert into cats(name, owner_id)
24select
25       random()::text,
26       owners.id
27from generate_series(1,10), owners; 
28     
29--delete the records in cats so we don't get a foreign key constraint violation
30delete  from cats
31where owner_id %10 = 1;
32
33
34---now we do the same delete on owners as we did before
35delete  from owners
36where id %10 = 1;