Example 1: Setting the display character set of an interactive
    session

    SQL> show character sets;
    Default character set is DEC_MCS
    National character set is DEC_MCS
    Identifier character set is DEC_MCS
    Literal character set is DEC_MCS
    Display character set is UNSPECIFIED
    SQL> set display character set 'SHIFT_JIS';
    SQL> show character sets;
    Default character set is DEC_MCS
    National character set is DEC_MCS
    Identifier character set is SHIFT_JIS
    Literal character set is SHIFT_JIS
    Display character set is SHIFT_JIS