Oracle: text of the running SQL queries

SELECT s.sid, s.serial#, st.sql_text sql_text
FROM v$session s, v$sql st, v$process p
WHERE s.sql_hash_value = st.hash_value
AND s.sql_address = st.address
AND s.paddr = p.addr
AND ( s.sid=&which_sid. )

Full text

SELECT x.sql_text
FROM v$session s,v$sqltext x
WHERE s.sql_address=x.address AND s.sid = &which_sid
ORDER BY sid, piece ASC