Deadlock detected when doing "ALTER USER"

From: Malcolm Dunnett <nothome_at_spammers.are.scum>
Date: Tue, 5 Dec 2006 09:34:05 -0800
Message-ID: <4575acfc$1@flight>

I've written a program that manages user accounts in my Oracle 9i database. It uses OCI to perform a number of dynamic sql statements. It works fine for any account that doesn't have SYSDBA/SYSOPER privilege, but if I try to use it to modify an account that has one of these privileges I get an ORA-00060 Deadlock detected error. I only have a single thread in this program. I do a select from various DBA tables to check the users current status before trying to do the alter user, eg:

SELECT * FROM DBA_USERS WHERE USERNAME = :USERNAME SELECT TABLESPACE_NAME,MAX_BYTES FROM DBA_TS_QUOTAS WHERE USERNAME =
:USERNAME

SELECT PRIVILEGE FROM DBA_SYS_PRIVS WHERE GRANTEE = :USERNAME ORDER BY PRIVILEGE
SELECT SYSDBA,SYSOPER FROM V$PWFILE_USERS WHERE USERNAME = :USERNAME SELECT GRANTED_ROLE,DEFAULT_ROLE FROM DBA_ROLE_PRIVS WHERE GRANTEE =
:USERNAME ORDER BY GRANTED_ROLE
but I don't select any of them for update and I even do a ROLLBACK just before trying to alter the user, but it doesn't help. The trace file shows:

SERVICE NAME:(SYS$USERS) 2006-12-05 09:05:48.749
SESSION ID:(360.195) 2006-12-05 09:05:48.749

DEADLOCK DETECTED
[Transaction Deadlock]

Current SQL statement for this session:
alter user SA_DUNNETT identified by ************

Deadlock graph:

                       ---------Blocker(s)--------  ---------Waiter(s)---------
Resource Name          process session holds waits  process session holds 
waits
PF-00000000-00000000        23     360     X             23     360

Am I correct in guessing this is a lock on the Password File? If so, any ideas what I may have done that is causing it to be locked or how I can free it before trying the update?

It's not a question of account privileges because I can perform the same operation using the same account through SQL/PLUS with no problem. Received on Tue Dec 05 2006 - 11:34:05 CST