Oracle Locks; Locks in Oracle

V$LOCKED_OBJECT

SELECT LO.session_id, LO.oracle_username, LO.os_user_name, 

       OBJ.object_name , OBJ.owner
  FROM V$LOCKED_OBJECT LO, 
       DBA_OBJECTS OBJ
WHERE LO.object_id = OBJ.object_id;

V$LOCKED_OBJECT + V$SESSION

SET LINESIZE 300

COL schemaname FOR A30

COL machine FOR A20

COL program FOR A20
COL module FOR A20

COL BLOCKING_SESSION FOR 999999

COL OS_USER_NAME FOR A20 

COL OBJECT_NAME FOR A30

COL kill_session for A60

SELECT DISTINCT

       SESS.sid, SESS.serial#, 

       SESS.schemaname, SESS.machine, 

       SESS.program, SESS.module, 

       SESS.blocking_session, LO.os_user_name, 

       OBJ.object_name , OBJ.owner, 

       SESS.sql_id,

'ALTER SYSTEM KILL SESSION ''' || SESS.sid || ',' || SESS.serial# ||''' IMMEDIATE;' kill_session

  FROM V$LOCKED_OBJECT LO, 

       DBA_OBJECTS OBJ, 

       V$SESSION SESS

WHERE LO.object_id = OBJ.object_id

  AND LO.session_id = SESS.sid;

V$LOCK

SELECT A.sid "blocking session", 

       B.sid "blocked session"  , 

       DECODE (A.block,1, A.sid ||' is Blocking '||B.sid,'Not Blocking'),  

       A.type "Lock Type"

FROM V$LOCK A, 

     V$LOCK B 

WHERE A.sid != B.sid 

  AND A.id1 = B.id1  

  AND A.id2 = B.id2 

  AND A.block = 1

  AND B.request > 0;

V$SESSION - lock time

SET LINESIZE 200

COL USERNAME FOR A20

COL MACHINE FOR A20

COL PROGRAM FOR A40

SELECT 

  sid, serial#, username, machine, program,

  blocking_session "blocking_session",

  sid "blocked_session",

  serial# "blocked_serial#", 

  seconds_in_wait/60 "wait_time(minutes)"

FROM V$SESSION

WHERE blocking_session IS NOT NULL

ORDER BY blocking_session;

V$SESSION - lock time + lock info

SELECT 

  ROUND(V_SESS_LOCKED.seconds_in_wait/60) "WAIT_TIME (MIN)",

  V_SESS_LOCKED.sid       locked_sid, 

  V_SESS_LOCKED.serial#   locked_serial, 

  V_SESS_LOCKED.username  locked_username, 

  V_SESS_LOCKED.machine   locked_machine, 

  V_SESS_LOCKED.program   locked_program,

  V_SESS_LOCKED.blocking_session blocking_session,

  V_SESS_LOCKED.sql_id    locked_sql,

  V_SESS_LOCKING.sid      locking_session,

  V_SESS_LOCKING.serial#  locking_serial,

  V_SESS_LOCKING.username locking_username,

  V_SESS_LOCKING.machine  locking_machine,

  V_SESS_LOCKING.program  locking_program,

  V_SESS_LOCKING.sql_id   locking_sql

FROM V$SESSION V_SESS_LOCKED,

     V$SESSION V_SESS_LOCKING

WHERE V_SESS_LOCKED.blocking_session IS NOT NULL

  AND V_SESS_LOCKED.blocking_session = V_SESS_LOCKING.sid

ORDER BY ROUND(V_SESS_LOCKED.seconds_in_wait/60) DESC;

Other useful SQLs
ALTER SYSTEM DISCONNECT SESSION '111,22222' IMMEDIATE;

ALTER SYSTEM KILL SESSION '111,22222' IMMEDIATE; 
SELECT paqddr FROM V$SESSION WHERE sid = '111';
SELECT spid FROM V$PROCESS WHERE addr = '0000000074C78SD1';

ORA-01873: the leading precision of the interval is too small

SELECT * FROM USER_JOBS
ORA-01873: the leading precision of the interval is too small

SELECT * FROM DBA_SCHEDULER_JOBS
ORA-01882: timezone region not found

After a removal of the suspected job, and recreating it again the issue was fixed.

"suspected job" - there was a lock in database, and the job session was terminated with ALTER SYSTEM KILL SESSION command.

BEGIN

 DBMS_JOB.remove(23);
 commit;
END;
/
SELECT * FROM USER_JOBS

Now is working!

Oracle Patch types

Oracle Patch types

Interim patches - contain a single bug fix or a collection of bug fixes provided as required

Diagnostic patches - intended to help diagnose or verify a fix

Bundle Patch Updates (BPUs) - a cumulative collection of fixes for a specific product or component

Patch Set Updates (PSUs) - a cumulative collection of high impact, low risk, and proven fixes for a specific product or component and Security Patch Updates

Security Patch Updates (SPU) - a cumulative collection of security bug fixes.  SPUs were formerly known as Critical Patch Updates (CPU).

System Patch - contains several sub-patches in a format that can be used by OPatchAuto.

Merge Label Request (MLR) - a merge of two or more fixes. MLR creation requires a label for the new set of merged code and a Patch Set Exception.

What to install?

RU - Release Update

Release Update

RU - Release Update

Oracle recommends that you keep your database software current by applying Release Updates (RUs).

RUs are listed in Primary Note for Database Proactive Patch Program (Doc ID 888.1)

Release Updates (RUs) are release quarterly: Third Tuesday of January, April, July and October. 

Each RU will be given a maximum of six Monthly Recommended Patches (MRPs), released monthly.

RUs are highly tested bundles of critical fixes which enable you to avoid known issues. 

They usually contain the following type of fixes: security, regression (bug), optimizer, and functional.

Monthly Recommended Patches (MRP)

Starting with update 19.17, Oracle is providing MRPs for Linux x86-64 to provide proactive patching between Release Updates.

Which patches to install for Oracle 19?

A. Oracle Database 19c Important Recommended One-off Patches (Doc ID 555.1)

B. Oracle Database 19c Proactive Patch Information - KB111276
C. Oracle Database 19c Proactive Patch Information (Doc ID 2521164.1)

This documents lists the latest patches for Oracle 19
DB RU - Database Release Update

19.29 DB RU - 21-Oct-2025 Patch 38291812

19.28 DB RU - 15-Jul-2025 Patch 37960098
19.27 DB RU - 15-Apr-2025 Patch 37642901
...

...
19.22 DB RU - Patch 35943157

19.21 DB RU - Patch 35643107 

19.20 DB RU - Patch 35320081

19.19 DB RU - Patch 35042068

B. Primary Note for Database Proactive Patch Program (Doc ID 888.1)

This documents lists patches for All oracle versions.
for example:

Oracle Database 19c Proactive Patch Information - KB111276

Applying a new patch:

Example: Apply patch 38291812

unzip p38291812_<version>_<platform>.zip

cd 38291812

Set PATH

>%PATH=$PATH:$ORACLE_HOME/OPatch

>%which opatch

/software/oracle/19c/OPatch/opatch

oracle@rh8-orclupgrade-1:~/patch_19-29/p6880880/OPatch>% opatch version

OPatch Version: 12.2.0.1.48

OPatch succeeded.

Check for conflict with the patch being installed

opatch prereq CheckConflictAgainstOHWithDetail -ph ./

Apply the Patch

opatch apply

Run datapatch utility. 

It executes any SQL scripts associated with the patches installed in the Oracle Home.

$ORACLE_HOME/OPatch/datapatch -verbose

Fix Permissions

Database release update patch installation involves relinking of libraries and executables to be updated. 

This can sometimes result in permissions changing and needing to be updated. 

Execute the following as root:

chown root $ORACLE_HOME/bin/extjob

chmod 4750 $ORACLE_HOME/bin/extjob

 

====================

By Example

====================

oracle@rh8-orclupgrade-1:~/patch_19-29/38291812/38291812>% opatch prereq CheckConflictAgainstOHWithDetail -ph ./

Oracle Interim Patch Installer version 12.2.0.1.41

Copyright (c) 2025, Oracle Corporation.  All rights reserved.

PREREQ session

Oracle Home       : /software/oracle/19c

Central Inventory : /software/oracle/oraInventory

   from           : /software/oracle/19c/oraInst.loc

OPatch version    : 12.2.0.1.41

OUI version       : 12.2.0.7.0

Log file location : /software/oracle/19c/cfgtoollogs/opatch/opatch2025-12-29_15-12-29PM_1.log

Invoking prereq "checkconflictagainstohwithdetail"

Prereq "checkConflictAgainstOHWithDetail" passed.

OPatch succeeded.

oracle@rh8-orclupgrade-1:~/patch_19-29/38291812/38291812>%

>%opatch lsinventory

Oracle Database 19c                                                  19.0.0.0.0

There are 1 products installed in this Oracle Home.

Interim patches (2) :

Patch  35943157     : applied on Sun Mar 17 11:24:52 UTC 2024

Unique Patch ID:  25527362

Patch description:  "Database Release Update : 19.22.0.0.240116 (35943157)"

   Created on 13 Jan 2024, 05:42:55 hrs UTC

Patch  29585399     : applied on Thu Apr 18 07:21:33 UTC 2019

Unique Patch ID:  22840393

Patch description:  "OCW RELEASE UPDATE 19.3.0.0.0 (29585399)"

After patch Database Release Update : 19.29:

>%opatch lsinventory

Patch  38291812     : applied on Mon Dec 29 16:24:21 UTC 2025

Unique Patch ID:  28130960

Patch description:  "Database Release Update : 19.29.0.0.251021 (38291812)"

   Created on 6 Oct 2025, 17:36:33 hrs UTC

   Bugs fixed:

Remove the patch backups, to save space

cd /software/oracle/19c/.patch_storage

du -sh *

2.9G    38291812_Oct_6_2025_17_36_33

rm -r 38291812_Oct_6_2025_17_36_33

>% datapatch -verbose

SQL Patching tool version 19.29.0.0.0 Production on Mon Dec 29 20:39:14 2025

Copyright (c) 2012, 2025, Oracle.  All rights reserved.

Log file for this invocation: /software/oracle/cfgtoollogs/sqlpatch/sqlpatch_49907_2025_12_29_20_39_14/sqlpatch_invocation.log

Connecting to database...OK

Gathering database info...done

Bootstrapping registry and package to current versions...done

Determining current state...done

Current state of interim SQL patches:

  No interim patches found

Current state of release update SQL patches:

  Binary registry:

    19.29.0.0.0 Release_Update 251002005342: Installed

  SQL registry:

    Applied 19.10.2.0.0 Release_Update_Revision 210515144132 successfully on 25-OCT-21 03.26.11.413859 PM

Adding patches to installation queue and performing prereq checks...done

Installation queue:

  No interim patches need to be rolled back

  Patch 32819074 (Database Release Update Revision : 19.10.2.0.0 (32819074)):

    Rollback from 19.10.2.0.0 Release_Update_Revision 210515144132 to 19.10.0.0.0 Release_Update 210108185017

  Patch 38291812 (Database Release Update : 19.29.0.0.251021 (38291812)):

    Apply from 19.10.0.0.0 Release_Update 210108185017 to 19.29.0.0.0 Release_Update 251002005342

  No interim patches need to be applied

Installing patches...

Patch installation complete.  Total patches installed: 2

Validating logfiles...done

Patch 32819074 rollback: SUCCESS

  logfile: /software/oracle/cfgtoollogs/sqlpatch/32819074/24234915/32819074_rollback_IGT_2025Dec29_20_40_16.log (no errors)

Patch 38291812 apply: SUCCESS

  logfile: /software/oracle/cfgtoollogs/sqlpatch/38291812/28130960/38291812_apply_IGT_2025Dec29_20_40_29.log (no errors)

SQL Patching tool complete on Mon Dec 29 20:44:25 2025

oracle@rh8-orclupgrade-2:/backup/ora_exp/patch_19-29/38291812>%

ORA-12034: materialized view log on "SCHEMA"."MY_SERVICE" younger than last refresh

Issue: Refresh Materialized View is giving this error:

ERROR at line 1:

ORA-12034: materialized view log on "SCHEMA"."MY_MVIEW" younger than last refresh

ORA-06512: at "SYS.DBMS_SNAPSHOT", line 794

ORA-06512: at "SYS.DBMS_SNAPSHOT", line 851

ORA-06512: at "SYS.DBMS_IREFRESH", line 683

ORA-06512: at "SYS.DBMS_REFRESH", line 195

ORA-06512: at "SCHEMA.REFRESH_PKG", line 19

ORA-06512: at line 2

Solution:

Complete refresh and then Fast Refresh the Materialized View

Example

BEGIN

 DBMS_MVIEW.refresh('MY_MVIEW' ,'C');

END;

/

BEGIN

 DBMS_MVIEW.refresh('MY_MVIEW' ,'F');

END;

/

Code Generator

-----------------------------------------

--Generate DBMS_REFRESH.refresh script

-----------------------------------------

COLUMN sql_cmd FORMAT A120 WORD_WRAP

SET LINESIZE 120

SET PAGESIZE 0

SET HEADING OFF

SET FEEDBACK OFF

SET NEWPAGE NONE

SET VERIFY OFF

SET ECHO OFF

SET SHOW OFF

SET TERMOUT OFF

-----------------------------------------

--Generate DBMS_REFRESH.refresh script

-----------------------------------------

COLUMN sql_cmd FORMAT A120 WORD_WRAP

SET LINESIZE 120

SET PAGESIZE 0

SET HEADING OFF

SET FEEDBACK OFF

SET NEWPAGE NONE

SET ECHO OFF

SET TERMOUT OFF

spool manual_refresh_mviews.sql 

PROMPT SET FEEDBACK ON

SELECT 'spool refresh_'||name||'.log;'||CHR(10)||

'PROMPT Start DBMS_MVIEW.refresh() of '||name||CHR(10)||

'BEGIN'||CHR(10)||

' DBMS_MVIEW.refresh('''||name||''' ,''C'');' ||CHR(10)||

' DBMS_MVIEW.refresh('''||name||''' ,''F'');' ||CHR(10)||

' COMMIT;'||CHR(10)||

'END;'||CHR(10)||

'/'||CHR(10)||

'spool off;' as sql_cmd

FROM DBA_REFRESH_CHILDREN

WHERE rname = 'MASTER_GROUP'

order by name;

PROMPT spool off

spool off;

@manual_refresh_mviews.sql