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select * from V$VERSION;
| BANNER |
|---|
| Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production |
| PL/SQL Release 11.2.0.2.0 - Production |
| CORE 11.2.0.2.0 Production |
| TNS for Linux: Version 11.2.0.2.0 - Production |
| NLSRTL Version 11.2.0.2.0 - Production |
with users(StudentStatus) as
(
select null from dual union all
select 99 from dual union all
select 98 from dual union all
select 8 from dual
)
select decode(nvl(StudentStatus,99),99,'Y','N') as status,
StudentStatus
from users
| STATUS | STUDENTSTATUS |
|---|---|
| Y | null |
| Y | 99 |
| N | 98 |
| N | 8 |