Don't worry! It's only stuff...

-- select a random row from table
SELECT column FROM 
   SELECT column FROM TABLE
   ORDER BY DBMS_RANDOM.VALUE
)
WHERE ROWNUM = 1
 
-- update materialized view
BEGIN
   dbms_snapshot.refresh('SCHEMA.MATERIALIZED_VIEW_NAME'); 
END;
 
-- view scheduler jobs
SELECT * FROM user_scheduler_jobs
 
-- get lock on table (NOWAIT)
SELECT username,v$lock.sid,TRUNC(id1/POWER(2,16)) rbs,BITAND(id1,TO_NUMBER('ffff','xxxx'))+0 slot,id2 seq,lmode,request
FROM v$lock, v$session
WHERE v$lock.TYPE = 'TX'
AND v$lock.sid = v$session.sid
 
-- set password
ALTER USER hr identified BY test