Configuration du schéma Oracle 11g R2 :
CREATE TABLE test (col1, col2, col3, col4, col5 ) AS
SELECT 1, 'A', 'B', 'C', 'D' FROM DUAL
UNION ALL SELECT 2, 'A', 'B', 'C', NULL FROM DUAL
UNION ALL SELECT 3, 'C', 'A', NULL, NULL FROM DUAL
UNION ALL SELECT 4, 'D', 'A', 'C', NULL FROM DUAL
UNION ALL SELECT 5, NULL, NULL, NULL, NULL FROM DUAL
UNION ALL SELECT 6, NULL, NULL, NULL, 'A' FROM DUAL
UNION ALL SELECT 7, 'B', NULL, NULL, 'A' FROM DUAL
UNION ALL SELECT 8, NULL, 'C', NULL, 'A' FROM DUAL;
Requête 1 :
S'il n'y a pas de NULL valeurs entre d'autres valeurs (cela introduira plusieurs virgules dans les lignes 7 et 8) :
SELECT col1,
TRIM( ',' FROM col2||','||col3||','||col4||','||col5 ) AS col2
FROM test
| COL1 | COL2 |
|------|---------|
| 1 | A,B,C,D |
| 2 | A,B,C |
| 3 | C,A |
| 4 | D,A,C |
| 5 | (null) |
| 6 | A |
| 7 | B,,,A |
| 8 | C,,A |
Les deux dernières requêtes fonctionneront pour tous les exemples :
Requête 2 :
SELECT col1,
TRIM( ',' FROM col2 || NVL2( col3, ','||col3, NULL ) || NVL2( col4, ','||col4, NULL ) || NVL2( col5, ','||col5, NULL ) ) AS col2
FROM test
| COL1 | COL2 |
|------|---------|
| 1 | A,B,C,D |
| 2 | A,B,C |
| 3 | C,A |
| 4 | D,A,C |
| 5 | (null) |
| 6 | A |
| 7 | B,A |
| 8 | C,A |
Requête 3 :
SELECT col1,
REGEXP_REPLACE( col2||','||col3||','||col4||','||col5, '(^|,),+|,+($)', '\1' ) AS col2
FROM test
| COL1 | COL2 |
|------|---------|
| 1 | A,B,C,D |
| 2 | A,B,C |
| 3 | C,A, |
| 4 | D,A,C |
| 5 | (null) |
| 6 | A |
| 7 | B,A |
| 8 | C,A |
