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CREATE TABLE tablename
(ID int, Category varchar2(2))
;
INSERT ALL
INTO tablename (ID, Category)
VALUES (1, 'NA')
INTO tablename (ID, Category)
VALUES (1, 'A')
INTO tablename (ID, Category)
VALUES (1, 'NA')
INTO tablename (ID, Category)
VALUES (2, 'B')
INTO tablename (ID, Category)
VALUES (2, 'NA')
INTO tablename (ID, Category)
VALUES (3, 'NA')
INTO tablename (ID, Category)
VALUES (4, 'C')
SELECT * FROM dual
;
7 rows affected
select id,
coalesce(max(case when category <> 'NA' then category end), 'NA') category
from tablename
group by id
| ID | CATEGORY |
|---|---|
| 2 | B |
| 4 | C |
| 3 | NA |
| 1 | A |