Server Administration :: How To Avoid Blocking Locks
Nov 8, 2011how to avoid blocking locks.
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Script To Find Blocking Locks More Than 30 Minutes
Jun 29, 2012writing a script where there is a blocking lock for more than 30 minutes ?
View 2 Replies View RelatedServer Administration :: Oracle 10g Blocking Sessions
Aug 19, 2010I am using oracle 10g as server in my lab. I faced some problems initially, but later after increasing the USERS tablespace it is working fine.
But there is still one problem. During the query execution some queries will be blocked and it doesn't leave any consequent queries to execute from the same user.
The blocked sessions will be displayed in the admin page under blocking sessions link. There is a option to kill the session. But when i do that, it affects all the users and the connection will be lost to all the users. again I have startup the database from beginning.
Server Administration :: Logwr Database Blocking Other Session
May 24, 2013One issue happens frequently in My database,Logwr process blocking other session,when i checked blocked session in v$session wait_class was commit and event was logfile sync,
EVENT# WAIT_CLASS
------ ----------------------------------------------------------------
116 Commit
116 Commit
116 Commit
116 Commit
116 Commit
116 Commit
115 Configuration
116 Commit
116 Commit
116 Commit
116 Commit
EVENT# WAIT_CLASS
------ ----------------------------------------------------------------
116 Commit
116 Commit
116 Commit
116 Commit
116 Commit
116 Commit
116 Commit
116 Commit
116 Commit
116 Commit
116 Commit
EVENT# WAIT_CLASS
------ ----------------------------------------------------------------
As per this we predicate Logbuffer Might be full so i just to reboot server,Note server was 32 Bit i can allocate only 1GB of SGA SYStem not allows me to increase SGA further. Server reboot is proper solution?
Server Administration :: User See Only Synonyms And Avoid Looking At Definitions
May 26, 2010I have granted connect,resource privilege to a user 'TestU' and have create several synonyms in the schema using the public database link. What worries me is that the user 'TestU' can view the all_ and users_ dictionary views, which makes him accessible to all public database links and all user specific objects definition.
Is there a way to restrict the user to see only the synonyms and avoid looking at their definitions
Server Administration :: How To Avoid Clear Password In Checkpoint File With Oracle DBCA
Nov 15, 2011I found there is clear password in the xml file in the process of Oracle instance creating. The process like below
1, when using the following process to create the instance
Login as user Oracle
/home/Oracle11home/bin/dbca -createDatabase -silent -templateName /home/Oracle11home/assistants/dbca/templates/Small.dbt -gdbName testDB -sid testSID -sysPassword [b]testpwd[/b] -systemPassword [b]testpwd[/b]
2. Found the file in $ORACLE_HOME/checkpoints/dbca/OraDb11g_home2_oracle_creation_checkpoint.xml , it listed the sys and system passwd (like testpwd for sys and system password) directly.
<CHECKPOINT LEVEL="MAJOR" NAME="db_oracle" DESC="db creation checkpoint" STATE="FAIL">
<PROPERTY_LIST>
<PROPERTY NAME="command" TYPE="STRING" VAL=" -silent -createDatabase -templateName Small.dbt -gdbName testDB -sid testpwd -sysPassword testpwd -systemPassword testpwd"/>
</PROPERTY_LIST>
</CHECKPOINT>
I hope to confirm :
1. what is the purpose for oracle to genate the checkpoint.
2, can we remove the file safely ?
3, if there is configuration that we can avoid to show clear password in checkpoint file?
Not Able To Find Blocking Session
Jan 10, 2013I am working on oracle 11g and AIX.We were facing some blocking issues.For more investigation on the blocking sesssion we checked active session history of the database.Like session 'A' was blocked by session 'B' ...Now if we check infromation about sessions 'A' it is showing that this session was blocked by session 'B'.
But when we checked for session 'B' informaiton ,it is not showing any thing...from where we can get infromation about session B and in what all scenarios active session history does not show information about blocking session....
Create Notification For Blocking Session
Aug 1, 2013I want to create notification/ or triggered mail to my client and my dba group which will occur while session and user has been blocked. I want to create this procedure in 12c OEM.
View 3 Replies View RelatedSQL & PL/SQL :: Disconnect User Who Are Blocking Sessions
Apr 11, 2011I have an assignment, i am suppose to disconnect all the users that are blocking sessions for over three hours. Below is my code which is not working
Create or replace procedure b_user IS
Declare
ssid number;
serial number;
Begin
[code]......
Blocking Port 7778 For A Range Of IP
Mar 18, 2013I am using Oracle Application Server 10gAs and Linux 4.
Our Test Application is access by users using 7778 port,i want just few users to access my test application(just admin user) and all other user should not get access to the application,even if they specify proper URL and port number.
Some access control policy using oracle application server 10gas.
Performance Tuning :: Identify Blocking Sessions
Feb 21, 2011My statspack reports are sometimes showing figures such as this from the Foreground Wait Events section:
Avg %Total
%Tim Total Wait wait Waits Call
Event Waits out Time (s) (ms) /txn Time
---------------------------- ------------ ---- ---------- ------ -------- ------
PL/SQL lock timer 1,430 100 6,982 4883 0.0 18.0
enq: TM - contention 3 0 6,438 ###### 0.0 16.6
db file sequential read 310,385 0 1,765 6 3.5 4.6
TCP Socket (KGAS) 12,593 13 180 14 0.1 .5
db file scattered read 23,673 0 87 4 0.3 .2
log file sync 19,409 0 82 4 0.2 .2
ksfd: async disk IO 1,680 0 29 17 0.0 .1
[code].....
The TM lock that occurred 3 times appears to be disastrous.Historically, this could be caused by missing indexes on foreign key columns.
How can I be alerted when this event occurs, so that I can do some real-time investigation into the sessions and the SQL that hit it? I suppose I could schedule a job to query v$lock/dba_waiters/dba_blockers every few minutes, but is there a better way? Any standard edition scripts for this?
Performance Tuning :: One Procedure Is Blocking And Another Is Locking It
Jan 25, 2011I am new to performance tuning. One procedure is blocking and another is locking it.
SQL> @glockers
Oracle OS
INSTANCE SID TY Usernam SERIAL# SPID Process LMODE REQUEST
---------- ------ -- ------- ---------- ------------ ------- ------------------------------------ ------------------------------------
[code]...
Object Locked But Can't Find Session / Process Blocking?
Sep 5, 2012I am on database 10.2.0.5, windows x64.
A developer calls me and tells me there are locks on 3 tables, and the locks are not released. So I run this to see which objects are locked by which session
select vlo.object_id, vlo.session_id, vlo.oracle_username, vlo.process
, DECODE(vlo.LOCKED_MODE, 0,'NONE', 1,'NULL', 2,'ROW SHARE', 3,'ROW EXCLUSIVE', 4,'SHARE', 5,'SHARE ROW EXCLUSIVE', 6,'EXCLUSIVE', NULL) LOCK_MODE
, do.owner, do.object_name, do.object_type
[code]...
When I run the query later, I sometimes get another session, but the lock stays. It seems here, that I am catching the same SID on new sessions, but it is probably a different serial # than the original session locking the table rows.
I get nothing from
select * from dba_waiters;
select * from dba_blockers;
Now why are those 3 tables row locked on some rows and I can't find the session responsible? The developer tells me his application crashed and the rows are locked since. So far ( keep in mind I am not a locking expert) the only way I found to release the locks is a DB bounce, its a test DB so no biggy.
Locks On Partition Table?
May 13, 2011I have the below questions on the locking mechanism in a partition table. Example I execute the below query,
delete from table_name subpartition (subpartition_name);
In that case,
1. If we perform above query, then which level of lock is happened to the table/partition & sub-partitions?
2. If we perform above query on same sub-partition of the same table with different where clause, what will happen?
3. If we perform above query for same table but different sub partition at same time, what will happen?
How To Check Locks In Database
Apr 13, 2013oracleDatabase version:11gR2
Os:solaris
how to check locks on database objects .it might be any lock? any select sql query to check database object levlel locks?what basis locks will occur?
SQL & PL/SQL :: DB Locks And Data Corruption?
Feb 25, 2012I have a sql script where triggers, procedures and functions are written. The triggers are causing db outages and causing problems in the application as well.
I am trying my best but with my low experience and expertise, am not able to make good progress.
Scenario: Course enrollments are inserted, deleted and updated in course_main and course_users table. This is done in gui as well as in background snapshot scheduler in a cron process. Course_main table contains all course enrollments and course_users table has crsmain_pk1 as foreign key.
Its quite a big file and am not sure what should i paste here so am uploading the file in txt.
Dead Locks - Not Releasing?
Oct 8, 2012We have encountered dead locks in EBS R12 Database 10.2.0.3. Even after bouncing the appstier and dbtier completely does not release the locks. How to clear the locks?
View 4 Replies View RelatedTable Locks In Exclusive Mode
Jan 6, 2011Under what scenarios do we lock a table in the exclusive mode.
View 1 Replies View RelatedUnexplainable Exclusive Transaction Locks?
Aug 23, 2010I have a job which runs the procedure below concurrently in 4 different sessions; It updates two tables.
PROCEDURE UPDATE_TAB_1_AND_TAB_2( traceIdTab IN pl_sql table,
individualIdTab IN pl_sql table,
fileSeqIdTab IN pl_sql table,
[Code].....
Each session is passed a sequence generated file ID; so the records processed in each session are completely different.
However, everytime this job runs, without failure, ONLY TWO sessions process concurrently, while the other two sessions are blocked. Once the first two have finished, then the remaining two sessions start work.
I have being monitoring the sessions on each run daily, and realized that the first two sessions processing are each holding a transaction exclusive lock on objects; hence blocking the other two sessions.
When I tried to find the objects that the two running sessions have a lock on, I cant seem to find anything by searching DBA_OBJECTS.object_id. However, when I look for the objects that are being waited on, its either a partitioned table or a partitioned index on either table_1 or table_2.
At first, I thought it was an ITL lock and after much analysis, I did not find anything which definitely pointed to an ITL lock. However, just to make sure, I increased the INITTRANS value from 2 to 5, but the problem did not go away.
At this point, I have applied all I know to understand the origin of the TX lock and how I can work around this situation, and decided to ask higher powers in Oracle for advise.
How To Analyze Locks And Performance Of Database
Sep 6, 2010I used v$locked_object and v$lock query to get the output.. But still I'm an one year exp in ORACLE. How to analyze the output of lock queries. what are the parameters to be analyzed on AWR report.
How to do proper performance checkup in ORACLE database as well analyze it.
Library Cache Locks By Dynamic DDL
Jun 30, 2011At a customers site I see lot of long lasting library cache locks during a complex ETL run. Several Sessions run in parallel and create Database tables with dynamic sql ( CREATE TABLE AS SELECT ....) .
Sometimes these procedures wait for each other with wait event 'Library Cache' . I presume that this is a side effect of the dynamic DDL in the stored procedures. Is that possible even when the Procs create different Tables but reference the same tables in their SELECT clauses ?
I presume that this is plausible but I need some arguments to convince my colleagues.
SQL & PL/SQL :: Session Is Killed But Locks Not Released
Jun 8, 2011On DB123, I have 2 KILLED sessions which are not disappearing and are holding locks on some tables in ONE schema.
The sessions belonged to ETL process and I have killed them last Friday after they have been hanging for 3 days. Unfortunately, I've also killed the corresponding Unix session - and now I've read on the Internet that in those cases the KILLED sessions might be hanging forever (=until the DB is shutdown).
how to remove these locks.
Performance Tuning :: How To Reduce Dml Locks
May 24, 2012After ran db health check, my database report gives the following details
dml_locks OK. dml_locks = 3396, transactions = 849.
PL/SQL :: How To View The Number Of Locks Defined For A Database
Aug 21, 2012How to view the number of locks defined for a database? I am using Oracle 10g.
How to calculate the number of locks for a given sql select statement?
say for example,
select a.eno,b.ename,c.salary,d.dob,e.address
from a,b,c,d,e
where...
...
..
Assume all of them are row level locking.
I want to calculate the number of locks . How many locks will be held while running the above query?
Networking And Gateways :: Select For Update - How To Kill Old Locks
Aug 3, 2011My code executes a Select For Update before updating a table. In some cases the network is disconnected and it causes the lock to hang. Then, I must kill the session in order to realese this lock.
I want to do it automatically. I would like to create a job that kills session that has a lock due to Select For Update that is not alive.
Forms :: Alert Windows Appear To Be Hidden And Application Locks Up
May 6, 2011I have a forms 11g application that of course has several message and alert windows that pop up when various errors or messages need to be displayed. This all works great on the developer machine, but when I try and run the form on another machine using any browser the message and alert windows appear to be hidden and the application locks up with the rolling bar across the bottom. I would guess it is waiting for a response, but I cannot get the window to appear.
Following is an example of an alert to be displayed:
declare
vAlertButton number;
begin
vAlertButton := show_alert('NO_EMAIL');
end;
RAC & Failsafe :: Inserting Large Data Locks The Destination Table In RAC
Oct 18, 2010Scenario:
Our application is using a two instance, one for the live active data and the other for the reports data. We have a process which moves the data from the live instance to reports instance every night. In a single db environment the process is working without any issues. However when we move to the RAC environment the reports db's (insert) in large table get locked and we are unable to insert data to the reports db.
What we are performing is:
Insert into my_table_rpt select * from may_table_live@db_link_to_livedb;
Issues:
my_table_rpt get locked
We have found the workaround by disable locking in destination and subsequent to the insert enable locking
ALTER TABLE my_table_rpt DISABLE TABLE LOCK;
Insert the data to the reports database table
Then
ALTER TABLE my_table_rpt ENABLE TABLE LOCK
Question:
Why does the large destination table (my_table_rpt) get locked in the RAC environment?
How To Avoid Ora-03134
Apr 19, 2011We have Oracle 8i, 9i, 10g and 11g. I installed oracle client 11gR2 and when I tried connecting to the database, its erroring out saying "ORA-03134 connections to this server version are no longer supported". What client version should I install in order to avoid this error?
View 2 Replies View RelatedSQL & PL/SQL :: How To Avoid Max Function
Feb 22, 2010I have two tables where I have to find the record for Max value of the column sap_pkid for every sap_id as in given table create script. This script is giving correct value but looking for a better way so that when data increses it doesn't hit the performance.
way where max can be avoided or a more tuned query .
create table tab1 (sapid number,
denid number);
create table tab2 (sap_pkid number ,sapid number,
denid number,
[code]...
SQL & PL/SQL :: Avoid Divisions By Zero?
Feb 25, 2013I have a query that performs the sum of a field and divides by the number of occurrences, got me a problem because if there are no occurrences would cause a divide by zero error in Query.
The solution I found might not have been the best, but at the time was possible.
I put a Case, when the sum of the number of occurrence is zero then return zero, otherwise performs the division of the sum of the values by the number of occurrences.
SELECT CLIENT_ID,
TO_NUMBER(TO_CHAR(DTPROC, ''YYYYMM'')),
DTPROC, EXCHANG_VAL,
[Code]....
Now this query is very slow, because have CASE,SUM and GROUP BY, so I need to optimize it.
do this validation (if the divisor is zero) more performance?