The default character set is the character set that SQL uses for
    the following elements:

    o  Database columns with a character data type that does not
       explicitly specify a character set

    o  Parameters that are not qualified by a character set

    You can specify the default character set at the session and
    database level. See the Oracle Rdb Introduction to SQL and Oracle
    Rdb Guide to Database Design and Definition for more detail about
    session and database character sets.

    You can specify the database default character set only when
    you create the database. You cannot change the database default
    character set after you have created the database.

    SQL uses DEC_MCS as the default character set, unless you have
    set the dialect to MIA or specified a default character set
    at the session level. You can override any default character
    set by specifying another default character set when creating a
    database.

    To specify the default character set, use one of the character
    set names listed in Supported Character Sets.

    The default character set does not affect the setting of the
    currency sign.

    When you compile SQL programs (either SQL module language or
    precompiled SQL), SQL uses the following to derive the default
    character set:

    o  The DEFAULT CHARACTER SET clause in the DECLARE ALIAS
       statement specifies the default character set of the alias
       at compile time. At run time, SQL uses the default character
       set of the attached database. At run time, you must ensure
       that the database default character set is identical to the
       default character set specified in the DECLARE ALIAS clause.

    o  The DEFAULT CHARACTER SET clause of the SQL module header or
       the DECLARE MODULE statement specifies the character set for
       parameters that are not qualified by a character set.

    o  In dynamic SQL, the SET DEFAULT CHARACTER SET statement
       specifies, at run time, the character set for parameters that
       are not qualified by a character set.

    o  The RDB$CHARACTER_SET logical name. However, the logical name
       is deprecated and will not be supported in a future release.