MySQL 8.0

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with recursive
  col1 as (
        select 1 id, '32,33' as column1
        union all
        select 2, '34,35'
    ),
  rec_col1 as (
        select id, column1 as remain, substring_index( column1, ',', 1 ) as column1
          from col1
      union all
        select id, substring( remain, char_length( column1 )+2 ),
            substring_index( substring( remain, char_length( column1 ) +2  ), ',', 1 )
          from rec_col1
          where char_length( remain ) > char_length( column1 ))
  select id, column1 from rec_col1
  order by id;
    


id
column1


1
32

1
33

2
34

2
35


with recursive
  col2 as (
        select 1 id, 'A,B' as column2
        union all
        select 2, 'C,D'),
    rec_col2 as (
        select id, column2 as remain, substring_index( column2, ',', 1 ) as column2
          from col2
      union all
        select id, substring( remain, char_length( column2 )+2 ),
            substring_index( substring( remain, char_length( column2 ) +2  ), ',', 1 )
          from rec_col2
          where char_length( remain ) > char_length( column2 )
    )
  select id, column2 from rec_col2
  order by id;
    


id
column2


1
A

1
B

2
C

2
D


with recursive
  col1 as (
        select 1 id, '32,33' as column1
        union all
        select 2, '34,35'
    ),
  col2 as (
        select 1 id, 'A,B' as column2
        union all
        select 2, 'C,D'),
  rec_col1 as (
        select id, column1 as remain, substring_index( column1, ',', 1 ) as column1
          from col1
      union all
        select id, substring( remain, char_length( column1 )+2 ),
            substring_index( substring( remain, char_length( column1 ) +2  ), ',', 1 )
          from rec_col1
          where char_length( remain ) > char_length( column1 )
    ),
    rec_col2 as (
        select id, column2 as remain, substring_index( column2, ',', 1 ) as column2
          from col2
      union all
        select id, substring( remain, char_length( column2 )+2 ),
            substring_index( substring( remain, char_length( column2 ) +2  ), ',', 1 )
          from rec_col2
          where char_length( remain ) > char_length( column2 )
    )
select group_concat(c2.column2, c1.column1 order by c2.column2, c1.column1) result
  from rec_col1 c1 join rec_col2 c2 on c1.id = c2.id 
  group by c2.id


result


A32,A33,B32,B33

C34,C35,D34,D35