The display character set is the character set SQL uses for
    determining the character set that text will automatically be
    translated to before display in interactive SQL or for text being
    returned by SQL to a user program.

    You can specify the display character set only for a session
    or a module by using the SET DISPLAY CHARACTER SET statement or
    the DISPLAY CHARACTER SET clause of the SQL module header, the
    DECLARE MODULE statement, or the DECLARE ALIAS statement.

    The choice of display character set is limited to those character
    sets that include ASCII characters. Identifier Character Set
    identifies the subset of character sets that you can use to
    specify the display character set.