Set the NLS_LANG parameter and connect as sqlplus and execute the command.
export NLS_LANG=AMERICAN_AMERICA.AL32UTF8
sqlplus / as sysdba
<your sql select statement>
Set the NLS_LANG parameter and connect as sqlplus and execute the command.
export NLS_LANG=AMERICAN_AMERICA.AL32UTF8
sqlplus / as sysdba
<your sql select statement>
Change the Encoding in SQL Developer Preferences as below Tools --> Preferences --> Environment --> Encoding --> UTF...