System Tables Views Oracle PLSQL

SQL>
SQL> select * from dual;
D
-
X
SQL>
SQL> select sql_text, hash_value, parsing_user_id
  2        from v$sql
  3       where upper(sql_text) = 'SELECT * FROM DUAL';
SQL_TEXT
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
HASH_VALUE PARSING_USER_ID
---------- ---------------
select * from DUAL
3649189949               0
select * from dual
 942515969               0
SQL_TEXT
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
HASH_VALUE PARSING_USER_ID
---------- ---------------
select * from dual
 942515969               0
3 rows selected.
SQL>
SQL> select sql_text, hash_value, parsing_user_id, optimizer_mode
  2       from v$sql
  3       where upper(sql_text) = 'SELECT * FROM DUAL';
SQL_TEXT
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
HASH_VALUE PARSING_USER_ID OPTIMIZER_
---------- --------------- ----------
select * from DUAL
3649189949               0 RULE
select * from dual
 942515969               0 RULE
SQL_TEXT
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
HASH_VALUE PARSING_USER_ID OPTIMIZER_
---------- --------------- ----------
select * from dual
 942515969               0 FIRST_ROWS
3 rows selected.
SQL>