How Oracle Handles Dead Locks?

Oracle server automatically detects dead locks. When a dead lock is detected, Oracle server will
select a victim transaction, and fail its statement that is blocked in the dead lock to break the dead
lock. The tutorial exercise below shows you an example of statements failed by Oracle server
because of dead locks:
(session 1)
SQL> connect HR/fyicenter
SQL> UPDATE fyi_links
SET notes='Session 1'
WHERE id=101;
1 row updated.
(session 2)
SQL> connect HR/fyicenter
SQL> UPDATE fyi_links
SET notes='Session 2'
WHERE id=110;
1 row updated.
SQL> UPDATE fyi_links
SET notes='Session 2'
WHERE id=101;
(blocked by lock on row id=101)
SQL> UPDATE fyi_links
SET notes='Session 1'
WHERE id=110;
(blocked by lock on row id=110)
ORA-00060: deadlock detected
while waiting for resource
(statement failed)
Oracle DBA FAQ - Managing Oracle User Accounts, Schema and Privileges
A collection of 23 FAQs on Oracle user account, schema and privileges. Clear answers are
provided with tutorial exercises on creating user accounts, granting privileges for session
connections, granting privileges for creating tables and inserting rows