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CREATE TABLE mytable (
ID int,
VALUE varchar(20)
);
insert into mytable values
(1, 'A'),
(2, 'A'),
(2, 'B'),
(2, 'C'),
(3, 'B');
Records: 5 Duplicates: 0 Warnings: 0
SELECT ID, 'A & B' as Value
FROM mytable
group by ID
HAVING COUNT(case when VALUE = 'A' then 1 end) + COUNT(case when VALUE = 'B' then 1 end) = 2
UNION ALL
select t.*
from mytable t
left join (
SELECT ID
FROM mytable
GROUP BY ID
HAVING COUNT(case when VALUE = 'A' then 1 end) + COUNT(case when VALUE = 'B' then 1 end) = 2
) as s on s.ID = t.ID and ( t.VALUE = 'A' or t.VALUE = 'B' )
where s.ID is null
order by ID
| ID | Value |
|---|---|
| 1 | A |
| 2 | C |
| 2 | A & B |
| 3 | B |