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CREATE TABLE tablename (
col1 NUMERIC,
col2 REAL,
col3 VARCHAR(10)
);
INSERT INTO tablename (col1,col2,col3) VALUES (11,11.1,'ABC');
1 rows affected
INSERT INTO tablename (col1,col2,col3) VALUES (12,12.2,'DEF');
1 rows affected
INSERT INTO tablename (col1,col2,col3) VALUES (12,12,'ABC');
1 rows affected
INSERT INTO tablename (col1,col2,col3) VALUES (13,13.5,'FEG');
1 rows affected
INSERT INTO tablename (col1,col2,col3) VALUES (13,13.7,'GJH');
1 rows affected
INSERT INTO tablename (col1,col2,col3) VALUES (13,13,'BDG');
1 rows affected
INSERT INTO tablename (col1,col2,col3) VALUES (14,14.1,'DEF');
1 rows affected
INSERT INTO tablename (col1,col2,col3) VALUES (15,15.1,'CEG');
1 rows affected
select distinct
t.col1,
case
when tt.col1 is null then t.col3
else tt.col3
end col3
from tablename t left join tablename tt
on tt.col1 = t.col1 and tt.col2 = t.col1
order by t.col1
| COL1 | COL3 |
|---|---|
| 11 | ABC |
| 12 | ABC |
| 13 | BDG |
| 14 | DEF |
| 15 | CEG |