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CREATE TABLE Users(StudentStatus VARCHAR2(100))
INSERT INTO Users
VALUES('99')
1 rows affected
INSERT INTO Users
VALUES(NULL)
1 rows affected
INSERT INTO Users
VALUES('100')
1 rows affected
SELECT StudentStatus, DECODE(StudentStatus, '99', 'Y', '', 'Y', 'N')
FROM Users
| STUDENTSTATUS | DECODE(STUDENTSTATUS,'99','Y','','Y','N') |
|---|---|
| 99 | Y |
| null | Y |
| 100 | N |