MySQL 5.7

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CREATE TABLE table1 (
  `ID` VARCHAR(100),
  `Val` VARCHAR(100),
  `Val2` VARCHAR(100),
  `Val3` VARCHAR(100)
);
INSERT INTO table1
  (`ID`, `Val`, `Val2`, `Val3`)
VALUES
  ('1','100','200','aa'),
  ('2','100','200','aa'),
  ('3','100','200','aa'),
  ('19','100','200','ab'),

  ('4','20','100','SD2'),
  ('5','20','100','SD1'),
  ('6','112','100','aa'),
  ('7','112','100','ab'),
  ('8','90','200','aa'),
  ('9','30','90','SF2'),
  ('10','30','90','SF1');
select distinct t.*
from (
  select val, val2
  from table1
  group by val, val2
  having count(*) > 1
) t1 
inner join (
 select val, val2, val3
  from table1
  group by val, val2, val3
  having count(*) = 1
) t2 
on t2.val = t1.val and t2.val2 = t1.val2
inner join (
 select val, val2, val3
  from table1
  group by val, val2, val3
  having count(*) = 1
) t3 
on t3.val = t1.val and t3.val2 = t1.val2 and t3.val3 <> t2.val3
inner join table1 t on t2.val = t.val and t2.val2 = t.val2 and t.val3 in (t2.val3, t3.val3)


ID
Val
Val2
Val3


4
20
100
SD2

5
20
100
SD1

6
112
100
aa

7
112
100
ab

9
30
90
SF2

10
30
90
SF1