Oracle 11g Release 2

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CREATE TABLE mytable (
  "Id" INTEGER,
  "Add" INTEGER,
  "Check" INTEGER,
  "RESULT" INTEGER,
  "Seq" INTEGER
);


INSERT ALL
INTO mytable ("Id", "Add", "Check", "RESULT", "Seq") VALUES ('1', '2', '1', '1', '10')
INTO mytable ("Id", "Add", "Check", "RESULT", "Seq") VALUES ('1', '2', '1', '2', '20')
INTO mytable ("Id", "Add", "Check", "RESULT", "Seq") VALUES ('2', '3', '4', '4', '30')
INTO mytable ("Id", "Add", "Check", "RESULT", "Seq") VALUES ('2', '3', '4', '4', '40')
INTO mytable ("Id", "Add", "Check", "RESULT", "Seq") VALUES ('3', '5', '2', '2', '50')
INTO mytable ("Id", "Add", "Check", "RESULT", "Seq") VALUES ('4', '2', '6', '2', '60')
SELECT * FROM dual
6 rows affected

SELECT *
FROM mytable m1
WHERE "Add" = "RESULT"
   OR "Seq" = (SELECT MIN("Seq") FROM mytable m2 WHERE m2."Add" = m1."Add")
  AND NOT EXISTS (SELECT * FROM mytable m3 WHERE m3."Add" = m1."Add" AND m3."Add" = m3."RESULT")


Id
Add
Check
RESULT
Seq


1
2
1
2
20

2
3
4
4
30

3
5
2
2
50

4
2
6
2
60