SQL> --The [] can be any character not present in the string literal.
SQL>
SQL> BEGIN
2 DBMS_OUTPUT.PUT_LINE('Oracle''s are BEAUTIFUL');
3 DBMS_OUTPUT.PUT_LINE(q'!Oracle's are BEAUTIFUL!');
4 DBMS_OUTPUT.PUT_LINE(q'[Oracle's are BEAUTIFUL]');
5 DBMS_OUTPUT.PUT_LINE(q'');
6 DBMS_OUTPUT.PUT_LINE(q'%Oracle's are BEAUTIFUL%');
7 END;
8 /
Oracle's are BEAUTIFUL
Oracle's are BEAUTIFUL
PL/SQL procedure successfully completed.
SQL>