create table A (colA varchar(1))
insert A
select '1' union all
select '2' union all
select 'A' union all
select 'B'
create table B (colB varchar(1))
insert B
select 'X' union all
select 'Y' union all
select 'A' union all
select 'B' union all
select 'C' union all
select 'D'