SQL recognizes the following types of character string literals:

    o  A quoted character string to represent printable characters
       from the session's literal character set.

    o  A quoted character string qualified by the name of a character
       set. The string represents printable characters from the named
       character set.

    o  A national character string literal (an N followed by a quoted
       character string), represents printable characters from the
       national character set.

    o  A hexadecimal character string (an X followed by a quoted
       character string) represents printable and nonprintable ASCII
       characters.