DECLARE
TYPE name_list IS TABLE OF VARCHAR2(40);
TYPE type_list IS TABLE OF VARCHAR2(20);

Tab_name name_list:=name_list();
Tab_type type_list:=type_list();

sql_str VARCHAR2(500);
BEGIN
sql_str := 'select uo.object_name,uo.object_type from user_objects uo where uo.object_type not in(''INDEX'',''LOB'') and uo.object_name not like ''BIN%''  order by uo.object_type desc';
EXECUTE IMMEDIATE sql_str BULK COLLECT INTO tab_name,tab_type;
FOR i IN Tab_name.FIRST.. Tab_name.LAST LOOP
if Tab_type(i) = 'TABLE'
  then
    sql_str := 'DROP ' || Tab_type(i) || ' ' || Tab_name(i) || ' cascade constraint';
  else
    sql_str := 'DROP ' || Tab_type(i) || ' ' || Tab_name(i) ;
end if;
dbms_output.put_line(sql_str);
EXECUTE IMMEDIATE sql_str;

END LOOP;
END;