MySQL 8.0

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create table table1 as
    select 1 as id, 1 as c_id, 1 as s_id, '2020-10-10' as p_date union all
    select 2 as id, 1 as c_id, 1 as s_id, '2020-10-11' as p_date union all
    select 3 as id, 2 as c_id, 1 as s_id, '2020-10-11' as p_date union all
    select 4 as id, 2 as c_id, 2 as s_id, '2020-10-12' as p_date 
create table table2 as
    select 1 as id, 1 as c_id, 1 as s_id, '2020-10-15' as s_date union all
    select 2 as id, 1 as c_id, 2 as s_id, '2020-10-16' as s_date union all
    select 3 as id, 2 as c_id, 2 as s_id, '2020-10-17' as s_date union all
    select 4 as id, 2 as c_id, 2 as s_id, '2020-10-17' as s_date 
select t1.c_id, t1.s_id, t1.p_date, t2.s_date
from table1 t1 left join
     table2 t2
     on t1.c_id = t2.c_id and t1.s_id = t2.s_id
union all
select t2.c_id, t2.s_id, t1.p_date, t2.s_date
from table2 t2 left join
     table1 t1
     on t1.c_id = t2.c_id and t1.s_id = t2.s_id
where t1.c_id is null;


c_id
s_id
p_date
s_date


1
1
2020-10-10
2020-10-15

1
1
2020-10-11
2020-10-15

2
1
2020-10-11
null

2
2
2020-10-12
2020-10-17

2
2
2020-10-12
2020-10-17

1
2
null
2020-10-16

c_id	s_id	p_date	s_date
1	1	2020-10-10	2020-10-15
1	1	2020-10-11	2020-10-15
2	1	2020-10-11	null
2	2	2020-10-12	2020-10-17
2	2	2020-10-12	2020-10-17
1	2	null	2020-10-16