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select value
from nls_session_parameters
where parameter = 'NLS_NUMERIC_CHARACTERS';
| VALUE |
|---|
| ., |
select to_char(231.12, '99999D99') from dual;
| TO_CHAR(231.12,'99999D99') |
|---|
| 231.12 |
select to_char(231.12, '99999D99','NLS_NUMERIC_CHARACTERS='',.''') from dual;
| TO_CHAR(231.12,'99999D99','NLS_NUMERIC_CHARACTERS='',.''') |
|---|
| 231,12 |