Using transaction-isolation tag

Hi
Anyone knows where the <transaction-isolation> tag must be setup in weblogic-ejb-jar.xml deployment descriptor ?
The DTD contains the tag but the WLS 8.1 SP3 doesn't recognize it.
Cheers !
Jin

Did you put the transaction-isolation under weblogic-ejb-jar element? Can you post your jar file here?
Anil

Similar Messages

About Transaction Isolation Levels...

Hi Everyone,
Please, i have a couple of questions regarding the Transaction Isolation Level, i will really appreciate any help on this...
1.- It is possible to know the transaction isolation level of all connections to the DB.??.. something like a select from v$session...
2.- I have an application that manage it's own connection pool and have set all of its connections to Transaction_read_commited. The problem is that for some reason, sometimes we get the "ORA-08177: can't serialize access for this transaction." Error. But what i know is that this ORA-08177 error only happens if the transaction isolation level is set to TRANSACTION_SERIALIZABLE. How can be that possible??. There is another application running that points to the same database that maybe uses TRANSACTION_SERIALIZABLE connections but even if this is happening, why the error is happening with my application!!?. Both applications are running on the same weblogic application server with oracle thin jdbc driver... (Oracle 9i)
Thanks in advance...
Victor.

thanks for the answers guys... i was reding several articles by Tom and also looking into Metalink documents... but my concern or my million dollar question is still: if exists the possibility to get the ORA-8177 error, even if i'm using Transaction isolation level READ_COMMITED???... what i learned from this articles is that if i use the Transaction SERIALIZABLE i may have this ORA-8177.. otherwise i wouldn't. right?... and if exists bugs related all that bugs may exists only if i define my connection as TRANSACTION_SERIALIZABLE.
I'm pretty sure that in my application ("Application A") i'm not using any TRANSACTION_SERIALIZABLE connections.... but i'm afraid that the other application ("Application B") is causing some blocks or conflicts with "Application A"... Is that possible?? (i think that in theory it's not)... But still if that's possible.. i return to my question... Why that ORA-8177 error raises on my "Application A".... this kind of error must be raising only in the "application B"....
Well maybe is something confusing.. an maybe is totally related to some developing mistake.... i just wanted to confirm some other point of views....
thanks again!!..
Victor

How best 2 use Shared AM in taskflow -new transaction/isolated data control

Hi all
I have nearly 800 screens in my app (under 20 or so different AMs), in which I access some Common VOs to work with by applying filtering (on Secondary Rowset, on Default Rowset using View criteria) on that, Used as View Accessor VO (List of Values) & Sorting. These common VOs are not DB driven but custom java datasource implemented and once it is loaded with data, data will not change. I use Dynamic tab shell to load the screens as separate task-flows. These task-flows are defined to be opened with New Tansaction/Isolated Datacontrol. Right now these Common VOs are shuttled in a default scoped AM (Say 'LookupAM') and attached the same as nested AM for the other AMs.
With the above design, the current behavior is whenever I load a task-flow in Dynamic tab shell, it creates a fresh instance for Shreen AM as well as LookUpAM (I tested by including println inside prepareSession() API of AM Implementation class).
I feel I'll get benefitted in terms of memory saving/performance when I use only one instance of LookupAM for all the screens. I prepared a sample app that mimic our actual application, but made the LookupAM to be a Application scoped shared AM (lets say SharedLookupAM). I've also made all the LOV View accessors comes from this Shared AM. When I run this sample, the behavior is every time I load the task-flow, still the framework creates Am instance for both screen AM and SharedLookupAM! Why so?
Question:
1. Considering my application design (i.e. consuming Shared AM instance from inside the task-flow which are desinged to be opened with new transaction/isolated datacontrol), will I get benefitted in any way If i use Shared AM. If so, what are all the possible type of usages of shared AM for my design?
2. Why framework creates instance of Shared AM everytime I load the task-flow. Does it meant task-flow settings takes the precedence over the Shared AM configuration and it overrides that?
Thanks in advance.
Raghu
Edited by: Raguraman on Apr 9, 2013 3:25 AM

Hi,
+1. Considering my application design (i.e. consuming Shared AM instance from inside the task-flow which are desinged to be opened with new transaction/isolated datacontrol), will I get benefitted in any way If i use Shared AM. If so, what are all the possible type of usages of shared AM for my design?+
Isolated data control settings are the most expensive settings you can have in ADF. They should be used only if the requirement for the task flow is to be atomic in that it can be committed or rolled back independently. If this is not the case for your use cases, then using shared data control is a better option to use. Note that my expectation to application scope AM is that the AM instance is created per user but that the data cache is only queried once.
+2. Why framework creates instance of Shared AM everytime I load the task-flow. Does it meant task-flow settings takes the precedence over the Shared AM configuration and it overrides that?+
Well, you tell it to do so. With the setting of isolated to the Data Control you explicitly tell it to open a new transaction in which case a new instance is created.
Frank

Transaction isolation issue in 6.1

How do I specify tx isolation in WebLogic 6.1 for local entities?
          I've tried a stanza in weblogic-ejb-jar.xml like this:
          <transaction-isolation>
          <isolation-level>TRANSACTION_SERIALIZABLE</isolation-level>
          <method>
          <ejb-name>Seat</ejb-name>
          <method-intf>Local</method-intf>
          <method-name>*</method-name>
          </method>
          </transaction-isolation>
          I get the following error message from ejbc:
          ERROR: Error processing 'META-INF/weblogic-ejb-jar.xml':
          .weblogic-ejb-jar.transaction-isolation.method.method-intf. must be one of
          the values: home,Home,remote,Remote
          Does this mean I should use "Remote" for the method-intf (a bit strange)? Or
          isn't tx isolation control implemented in 6.1 for local entities?
          I've encountered this problem in 6.1 beta and the final release.
          Thanks,
          Rod


Thanks Seth.This works.
          By the way, there's an error in the 6.1 documents. The table of available
          values for isolation-level lists
          Serializable | ReadCommitted | ReadUncommitted | RepeatableRead
          In fact, ejbc will accept only
          TRANSACTION_SERIALIZABLE,TRANSACTION_READ_COMMITTED,TRANSACTION_READ_COMMITT
          ED_FOR_UPDATE,TRANSACTION_READ_UNCOMMITTED,TRANSACTION_REPEATABLE_READ
          These values are included in the text below the table.
          http://e-docs.bea.com/wls/docs61/ejb/reference.html#1072573
          Regards,
          Rod
          "Seth White" <[email protected]> wrote in message
          news:[email protected]...
          >
          > Rod,
          >
          > Looks like there's a bug that won't let you specify 'Local' as the value
          for
          > method-intf. As a temporary workaround, you may want to leave out
          > the method-intf tag.
          >
          > Seth
          >
          > Rod Johnson wrote:
          >
          > > How do I specify tx isolation in WebLogic 6.1 for local entities?
          > >
          > > I've tried a stanza in weblogic-ejb-jar.xml like this:
          > >
          > > <transaction-isolation>
          > > <isolation-level>TRANSACTION_SERIALIZABLE</isolation-level>
          > > <method>
          > > <ejb-name>Seat</ejb-name>
          > > <method-intf>Local</method-intf>
          > > <method-name>*</method-name>
          > > </method>
          > > </transaction-isolation>
          > >
          > > I get the following error message from ejbc:
          > >
          > > ERROR: Error processing 'META-INF/weblogic-ejb-jar.xml':
          > > .weblogic-ejb-jar.transaction-isolation.method.method-intf. must be one
          of
          > > the values: home,Home,remote,Remote
          > >
          > > Does this mean I should use "Remote" for the method-intf (a bit
          strange)? Or
          > > isn't tx isolation control implemented in 6.1 for local entities?
          > >
          > > I've encountered this problem in 6.1 beta and the final release.
          > >
          > > Thanks,
          > > Rod
          >

OCJ4's EJB transaction isolation level

Hello, all
Does OC4J supports various transaction isolation level?
I am using JDeveloper to create and deploy
EJBs and all I can find is transaction attributes,
and not isolation level. The book I am currently reading
suggests that there's tx isolation setting in BEA
WebLogic.
If anybody has found a way to do this in OC4J + Jdeveloer,
or if it is ever required, let me know.
Thanks

Hi
You can specify the isolation level using the "isolation" attribute of the "entity-deployment" tag.
Ex:
<entity-deployment name="MyEJB" isolation="serializable">
Go through the DTD for details :
http://xmlns.oracle.com/ias/dtds/orion-ejb-jar.dtd
--Shrini

Bug in Oracle's handling of transaction isolation levels?

Hello,
I think there is a bug in Oracle 9i database related to serializable transaction isolation level.
Here is the information about the server:
Operating System:     Microsoft Windows 2000 Server Version 5.0.2195 Service Pack 2 Build 2195
System type:          Single CPU x86 Family 6 Model 8 Stepping 10 GenuineIntel ~866 MHz
BIOS-Version:          Award Medallion BIOS v6.0
Locale:               German
Here is my information about the client computer:
Operaing system:     Microsoft Windows XP
System type:          IBM ThinkPad
Language for DB access: Java
Database information:
Oracle9i Enterprise Edition Release 9.2.0.1.0 - Production
With the Partitioning, OLAP and Oracle Data Mining options
JServer Release 9.2.0.1.0 - Production
The database has been set up using the default settings and nothing has been changed.
To reproduce the bug, follow these steps:
1. Create a user in 9i database called 'kaon' with password 'kaon'
2. Using SQL Worksheet create the following table:
CREATE TABLE OIModel (
modelID int NOT NULL,
logicalURI varchar (255) NOT NULL,
CONSTRAINT pk_OIModel PRIMARY KEY (modelID),
CONSTRAINT logicalURI_OIModel UNIQUE (logicalURI)
3. Run the following program:
package test;
import java.sql.*;
public class Test {
public static void main(String[] args) throws Exception {
java.util.Locale.setDefault(java.util.Locale.US);
Class.forName("oracle.jdbc.OracleDriver");
Connection connection=DriverManager.getConnection("jdbc:oracle:thin:@schlange:1521:ORCL","kaon","kaon");
DatabaseMetaData dmd=connection.getMetaData();
System.out.println("Product version:");
System.out.println(dmd.getDatabaseProductVersion());
System.out.println();
connection.setAutoCommit(false);
connection.setTransactionIsolation(Connection.TRANSACTION_SERIALIZABLE);
int batches=0;
int counter=2000;
for (int outer=0;outer<50;outer++) {
for (int i=0;i<200;i++) {
executeUpdate(connection,"INSERT INTO OIModel (modelID,logicalURI) VALUES ("+counter+",'start"+counter+"')");
executeUpdate(connection,"UPDATE OIModel SET logicalURI='next"+counter+"' WHERE modelID="+counter);
counter++;
connection.commit();
System.out.println("Batch "+batches+" done");
batches++;
protected static void executeUpdate(Connection conn,String sql) throws Exception {
Statement s=conn.createStatement();
try {
int result=s.executeUpdate(sql);
if (result!=1)
throw new Exception("Should update one row, but updated "+result+" rows, query is "+sql);
finally {
s.close();
The program prints the following output:
Product version:
Oracle9i Enterprise Edition Release 9.2.0.1.0 - Production
With the Partitioning, OLAP and Oracle Data Mining options
JServer Release 9.2.0.1.0 - Production
Batch 0 done
Batch 1 done
java.lang.Exception: Should update one row, but updated 0 rows, query is UPDATE OIModel SET logicalURI='next2571' WHERE modelID=2571
     at test.Test.executeUpdate(Test.java:35)
     at test.Test.main(Test.java:22)
That is, after several iterations, the executeUpdate() method returns 0, rather than 1. This is clearly an error.
4. Leave the database as is. Replace the line
int counter=2000;
with line
int counter=4000;
and restart the program. The following output is generated:
Product version:
Oracle9i Enterprise Edition Release 9.2.0.1.0 - Production
With the Partitioning, OLAP and Oracle Data Mining options
JServer Release 9.2.0.1.0 - Production
Batch 0 done
Batch 1 done
java.sql.SQLException: ORA-08177: can't serialize access for this transaction
     at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:134)
     at oracle.jdbc.ttc7.TTIoer.processError(TTIoer.java:289)
     at oracle.jdbc.ttc7.Oall7.receive(Oall7.java:573)
     at oracle.jdbc.ttc7.TTC7Protocol.doOall7(TTC7Protocol.java:1891)
     at oracle.jdbc.ttc7.TTC7Protocol.parseExecuteFetch(TTC7Protocol.java:1093)
     at oracle.jdbc.driver.OracleStatement.executeNonQuery(OracleStatement.java:2047)
     at oracle.jdbc.driver.OracleStatement.doExecuteOther(OracleStatement.java:1940)
     at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:2709)
     at oracle.jdbc.driver.OracleStatement.executeUpdate(OracleStatement.java:796)
     at test.Test.executeUpdate(Test.java:33)
     at test.Test.main(Test.java:22)
This is clearly an error - only one transaction is being active at the time, so there is no need for serialization of transactions.
5. You can restart the program as many times you wish (by chaging the initial counter value first). The same error (can't serialize access for this transaction) will be generated.
6. The error doesn't occur if the transaction isolation level isn't changed.
7. The error doesn't occur if the UPDATE statement is commented out.
Sincerely yours
     Boris Motik

I have a similar problem
I'm using Oracle and serializable isolation level.
Transaction inserts 4000 objects and then updates about 1000 of these objects.
Transactions sees inserted objects but cant update them (row not found or can't serialize access for this transaction are thrown).
On 3 tries for this transaction 1 succeds and 2 fails with one of above errors.
No other transactions run concurently.
In read commited isolation error doesn't arise.
I'm using plain JDBC.
Similar or even much bigger serializable transaction works perfectly on the same database as plsql procedure.
I've tried oci and thin (Oracle) drivers and oranxo demo (i-net) driver.
And this problems arises on all of this drivers.
This problem confused me so much :(.
Maby one of Oracle users, developers nows cause of this strange behaviour.
Thanx for all answers.

Setting transaction isolation level in Weblogic 5.1

          Hi,
          I'm using Weblogic server5.1 and i'm trying to set the isolation level on one
          of my session bean. Below is the code :
          <weblogic-ejb-jar>
          <weblogic-enterprise-bean>
          <ejb-name>chargeMgr</ejb-name>
          <jndi-name>chargeMgr</jndi-name>
          <transaction-isolation>
          <isolation-level>Serializable</isolation-level>
          <method>
          <ejb-name>chargeMgr</ejb-name>
          <method-intf>Remote</method-intf>
          <method-name>*</method-name>
          </method>
          </transaction-isolation>
          </weblogic-enterprise-bean>
          </weblogic-ejb-jar>
          I have checked the syntax against the weblogic documentation.
          However, when i try to jar the beans up into the jar file (weblogic.ejbc), it
          give me the following error :
          org.xml.sax.SAXParseException: Element "weblogic-enterprise-bean" allows no further
          input; "transaction-isolation" is not allowed.
          Can anyone help?
          Regards.


yes, only in weblogic-ejb-jar.xml , and you can see that from the DTD
          source.
          thanks
          Yu
          "cw lee" <[email protected]> wrote in message
          news:[email protected]...
          >
          > thanks for ur advice.
          >
          > one thing i forgot to mention is that the isolation-level was specified in
          weblogic-ejb-jar.xml.
          > Do u mean that it must be placed in weblogic-cmp-rdbms-jar.xml and not
          weblogic-ejb-jar.xml
          > ?
          >
          > Are the codes u suggested to be in weblogic-ejb-jar.xml or
          weblogic-cmp-rdbms-jar.xml
          > ?
          >
          > Regards.
          >
          >
          >
          > "Yu Tian" <[email protected]> wrote:
          > >the right name for Seriealizable should be: TRANSACTION_SERIALIZABLE.
          > >so the
          > >DD looks like:
          > >
          > ><?xml version="1.0"?>
          > >
          > ><!DOCTYPE weblogic-ejb-jar PUBLIC '-//BEA Systems, Inc.//DTD WebLogic
          > >5.1.0
          > >EJB//EN' 'http://www.bea.com/servers/wls510/dtd/weblogic-ejb-jar.dtd'>
          > >
          > ><weblogic-ejb-jar>
          > > <weblogic-enterprise-bean>
          > > <ejb-name>containerManaged</ejb-name>
          > > <caching-descriptor>
          > > <max-beans-in-cache>1000</max-beans-in-cache>
          > > </caching-descriptor>
          > > <persistence-descriptor>
          > > <persistence-type>
          > > <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
          > > <type-version>5.1.0</type-version>
          > > <type-storage>META-INF/weblogic-cmp-rdbms-jar.xml</type-storage>
          > > </persistence-type>
          > > <persistence-use>
          > > <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
          > > <type-version>5.1.0</type-version>
          > > </persistence-use>
          > > </persistence-descriptor>
          > > <jndi-name>containerManaged.AccountHome</jndi-name>
          > > <transaction-isolation>
          > > <isolation-level>TRANSACTION_SERIALIZABLE</isolation-level>
          > > <method>
          > > <ejb-name>containerManaged</ejb-name>
          > > <method-name>*</method-name>
          > > </method>
          > > </transaction-isolation>
          > > </weblogic-enterprise-bean>
          > > </weblogic-ejb-jar>
          > >
          > >Thanks
          > >
          > >Yu
          > >
          > >
          > >"cw lee" <[email protected]> wrote in message
          > >news:[email protected]...
          > >>
          > >> Hi,
          > >>
          > >> I'm using Weblogic server5.1 and i'm trying to set the isolation level
          > >on
          > >one
          > >> of my session bean. Below is the code :
          > >>
          > >> <weblogic-ejb-jar>
          > >> <weblogic-enterprise-bean>
          > >> <ejb-name>chargeMgr</ejb-name>
          > >> <jndi-name>chargeMgr</jndi-name>
          > >> <transaction-isolation>
          > >> <isolation-level>Serializable</isolation-level>
          > >> <method>
          > >> <ejb-name>chargeMgr</ejb-name>
          > >> <method-intf>Remote</method-intf>
          > >> <method-name>*</method-name>
          > >> </method>
          > >> </transaction-isolation>
          > >> </weblogic-enterprise-bean>
          > >> </weblogic-ejb-jar>
          > >>
          > >> I have checked the syntax against the weblogic documentation.
          > >> However, when i try to jar the beans up into the jar file
          (weblogic.ejbc),
          > >it
          > >> give me the following error :
          > >>
          > >> org.xml.sax.SAXParseException: Element "weblogic-enterprise-bean"
          allows
          > >no further
          > >> input; "transaction-isolation" is not allowed.
          > >>
          > >> Can anyone help?
          > >>
          > >> Regards.
          > >>
          > >
          > >
          >

Transaction Isolation Level to Read UnCommited in Non OLTP Database

HI,
We are having a database which for NOT OLTP process. That is OLAP DB. Operation on that DB is only Select and (Incremental Insert - FOR DWH ) not Update/Delete and we are performing ROLAP operations in that DB.
By Default SQL Server DB isolation Level is READ COMMITTED.AS Our DB IS OLAP SQL Server DB we need to change the isolation level toRead Uncommited. We google it down but We can achive in
Transaction level only by SET isoaltion Level TO Read UNCOMMITED
or ALLOW_SNAPSHOT_ISOLATION ON or READ_COMMITTED_SNAPSHOT
Is there any other way if we can Change the Database isolation level to READ uncommitedfor Entire Database?, insteads of achiving in Transaction Level or With out enabling SET ALLOW_SNAPSHOT_ISOLATION ON or READ_COMMITTED_SNAPSHOT
Please use Marked as Answer if my post solved your problem and use Vote As Helpful if a post was useful.
Please use Marked as Answer if my post solved your problem and use Vote As Helpful if a post was useful.

Hi,
My first question would be why do you want to change Isolation level to read uncommitted, are you aware about the repercussions you will get dirty data, a wrong data.
Isolation level is basically associated with the connection so is define in connection.
>> Transaction level only by SET isoaltion Level TO Read UNCOMMITED or ALLOW_SNAPSHOT_ISOLATION ON or READ_COMMITTED_SNAPSHOT
Be cautious Read UNCOMMITED and Snapshot isolation level are not same.The former is pessimistic Isolation level and later is Optimistic.Snapshot isolation levels are totally different from read uncommitted as snapshot Isolation level
uses row versioning.I guess you wont require snapshot isolation level in O:AP DB.
Please read below blog about setting Isolation level Server wide
http://blogs.msdn.com/b/ialonso/archive/2012/11/26/how-to-set-the-default-transaction-isolation-level-server-wide.aspx
Please mark this reply as the answer or vote as helpful, as appropriate, to make it useful for other readers
My TechNet Wiki Articles

Transaction Isolation Levels in weblogic-cmp-rdbms-jar.xml

Hi All,
Iam using ejb 1.1 specification with weblogic 5.1. We can set the transaction
isolation levels for the methods in the
weblogic-ejb-jar.xml. There is also a provision for setting this isolation level
in the weblogic-cmp-rdbms-jar.xml. Now is there any difference between setting
the isolation levels in these two ways.
Help me asap.

The CMP setting has been deprecated. You can set it for all types of
EJBs in the weblogic-ejb-jar.xml
-- Rob
chandru wrote:
Hi All,
Iam using ejb 1.1 specification with weblogic 5.1. We can set the transaction
isolation levels for the methods in the
weblogic-ejb-jar.xml. There is also a provision for setting this isolation level
in the weblogic-cmp-rdbms-jar.xml. Now is there any difference between setting
the isolation levels in these two ways.
Help me asap.

Locking issues with transaction-isolation levels

          I believe that my program is suffering from some sort of deadlock, and I was hoping
          for some feedback.
          I am helping to develop a trading system
          using EJBs, Oracle 9i, and Bea Weblogic 7.0. The system provides an entity EJB
          called LiveOrder that exposes several finder methods, most of which return java.util.Collections
          of LiveOrder EJBs.
          In weblogic-ejb-jar.xml, I have set the transaction isolation-levels for these
          finders to TRANSACTION_READ_COMMITTED_FOR_UPDATE (b/c TRANSACTION_SERIALIZABLE
          isn't really supported by Oracle), in an effort to eliminate phantom reads, which
          occur frequently if I do not use this isolation level. These finders all use transaction
          attribute 'Required'.
          It is my understanding that any transaction that calls any of these finders either
          will lock the database if no other transaction already owns the lock, or will
          wait until the lock is released if another transaction owns that lock. It also
          is my understanding that a transaction that owns a lock will always release any
          locks acquired upon expiration of that transaction (whether that be via commit
          or via rollback).
          However, this doesn't always appear the case: I have noticed occassionally that
          several clients "hang," as they wait for the lock that, for some reason, is not
          being released by its transaction. There do not appear to be any exceptions thrown
          by the system prior to the system hanging, and the Weblogic administration tool
          states that all transactions have been committed.
          If it helps, I have included the general algorithm for the main (i.e., most expensive)
          transaction:
          1. a client calls a stateless session EJB's processOrder method (which should
          implicitly start a new transaction, b/c this method has attibute 'RequiresNew')
          2. the transaction invokes the LiveOrder finder method (this should lock the DB,
          so subsequent callers should block until the lock is released).
          3. the transaction invokes another LiveOrder finder method, returning a separate
          set of data.
          4. the transaction invokes a finder method from a separate entity EJB (called
          Security), which maps to a "read-only" table in the DB (default transaction-isolation
          level, Required attribute).
          5. the transaction invokes a finder method from yet another separate entity EJB
          (called SecurityMarketValues), which maps to some other table (not read-only)
          in the DB (again, default transaction-isolation level, Required attribute).
          6. the transaction writes to the SecurityMarketValues entity EJB.
          7. the transaction writes to the LiveOrders retrieved from steps 2 and 3.
          8. the transaction ends by exiting method processOrder (thus releasing the locks
          on the LiveOrder table in the DB).
          In the system, there also exist other transactions that occassionally call the
          LiveOrder EJB finder methods, but only briefly to take a "snapshot" of the live
          order table (i.e., these transactions do not make calls to other DB tables, and
          close transactions almost immediately after starting them)
          Like I mentioned before, the system sometimes works, and sometimes it hangs. Any
          ideas? I'm running out...


Jon,
          If there was an Oracle deadlock the DB would resolve it momentarily and
          will ultimately choose one transaction and throw an exception so it's
          not a DB deadlock.
          Take a thread dump at the very moment your system seems to be hanging
          and look at what the threads are doing.
          From your description it's not very unlikely that those threads of
          yours that take snapshots of the data will not disrupt the transactions
          so you may be surprised by the thread dumps that this is actually what
          happens -- those snapshot thread wait for some lock while holding locks
          needed by you other threads and it just slows down the system.
          Regards,
          Dejan
          Jon Gadzik wrote:
          >I believe that my program is suffering from some sort of deadlock, and I was hoping
          >for some feedback.
          >
          >I am helping to develop a trading system
          >using EJBs, Oracle 9i, and Bea Weblogic 7.0. The system provides an entity EJB
          >called LiveOrder that exposes several finder methods, most of which return java.util.Collections
          >of LiveOrder EJBs.
          >
          >In weblogic-ejb-jar.xml, I have set the transaction isolation-levels for these
          >finders to TRANSACTION_READ_COMMITTED_FOR_UPDATE (b/c TRANSACTION_SERIALIZABLE
          >isn't really supported by Oracle), in an effort to eliminate phantom reads, which
          >occur frequently if I do not use this isolation level. These finders all use transaction
          >attribute 'Required'.
          >
          >It is my understanding that any transaction that calls any of these finders either
          >will lock the database if no other transaction already owns the lock, or will
          >wait until the lock is released if another transaction owns that lock. It also
          >is my understanding that a transaction that owns a lock will always release any
          >locks acquired upon expiration of that transaction (whether that be via commit
          >or via rollback).
          >
          >However, this doesn't always appear the case: I have noticed occassionally that
          >several clients "hang," as they wait for the lock that, for some reason, is not
          >being released by its transaction. There do not appear to be any exceptions thrown
          >by the system prior to the system hanging, and the Weblogic administration tool
          >states that all transactions have been committed.
          >
          >If it helps, I have included the general algorithm for the main (i.e., most expensive)
          >transaction:
          >
          >1. a client calls a stateless session EJB's processOrder method (which should
          >implicitly start a new transaction, b/c this method has attibute 'RequiresNew')
          >
          >2. the transaction invokes the LiveOrder finder method (this should lock the DB,
          >so subsequent callers should block until the lock is released).
          >
          >3. the transaction invokes another LiveOrder finder method, returning a separate
          >set of data.
          >
          >4. the transaction invokes a finder method from a separate entity EJB (called
          >Security), which maps to a "read-only" table in the DB (default transaction-isolation
          >level, Required attribute).
          >
          >5. the transaction invokes a finder method from yet another separate entity EJB
          >(called SecurityMarketValues), which maps to some other table (not read-only)
          >in the DB (again, default transaction-isolation level, Required attribute).
          >
          >6. the transaction writes to the SecurityMarketValues entity EJB.
          >
          >7. the transaction writes to the LiveOrders retrieved from steps 2 and 3.
          >
          >8. the transaction ends by exiting method processOrder (thus releasing the locks
          >on the LiveOrder table in the DB).
          >
          >
          >In the system, there also exist other transactions that occassionally call the
          >LiveOrder EJB finder methods, but only briefly to take a "snapshot" of the live
          >order table (i.e., these transactions do not make calls to other DB tables, and
          >close transactions almost immediately after starting them)
          >
          >Like I mentioned before, the system sometimes works, and sometimes it hangs. Any
          >ideas? I'm running out...
          >
          >
          >
          >

Issues with transaction isolation levels (BEA-631 exceptions)

My intended EJB application will have a session bean that uses two very similar entity beans that will be mapped to different databases; in my test version the entity beans use the same database.
The final application will need XA transactions with isolation=serializable (beans may be in Oracle, DB2, or MSSQL databases); high probability of concurrent potentially interfering transactions.
My test example works (Windows XP, WebLogic 8.1, Oracle 9.2) with both BEA's Oracle driver, and the Oracle driver but only when I set a transaction isolation on the session bean as the Oracle specific "transactionreadcommitedforupdate".
If I try using "transactionserializable", I get an exception like the following when my session-bean first tries to find an entity bean:
<2/09/2005 10:13:43 AM EST> <Warning> <Common> <BEA-000631> <Unknown resource "weblogic.jdbc.common.internal.ConnectionEnv@1f13e99" being released to pool "BEAOraclePool". Printing out current pool contents.>
(similar response with both drivers).
Please could someone explain what is wrong and why setting isolation serializable causes problems. How
should I fix things?

Hi. What version of 8.1 is this?
If you can easily reproduce this
we may either have a fix, or will
want to debug this.
Joe
Neil Gray wrote:
The bit about "cleaning up vendor connections" was from the comment by Imeshev that was earlier in this thread.
The context:
Application does involve possibility of two concurrent transactions trying to change the same row of a datatable; as isolation level is repeatableread or serializable, this will result in some exceptions. Sometimes exceptions handled ok, sometimes they cause problems.
Particular case illustrated below is when working with DB2. As I understand it, the two concurrent EJBs both make read requests (presumably acquiring read locks) then make update requests - if they happen to share a row this will block. I don't know enough about DB2 to know what controls its detection of problems. In practice I see db2 typically sending back an error to one of requestors in less than 1 second, but sometimes several seconds may elapse before the error response gets sent (I have observ
ed actual net traffic).
If transaction gets timed out in WebLogic (I've curently got a generous 8 second timeout setting in JTA tab) then there are problems.
First of two exceptions shown here is for normal case where db2 returned an error and it was handled ok:
11111111111111111
####<30/09/2005 10:55:39 AM EST> <Error> <EJB> <ATP-NL2-RS3> <examplesServer> <ExecuteThread: '12' for queue: 'weblogic.kernel.Default'> <<anonymous>> <> <BEA-010026> <Exception occurred during commit of transaction Name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)],Xid=BEA1-1D5B56A9177C58E3D95B(17477508),Status=Rolled back. [Reason=weblogic.utils.NestedRuntimeException: Error writing from beforeCompletion - with nested exception:
[weblogic.jdbc.base.BaseBatchUpdateException: [BEA][DB2 JDBC Driver]Abnormal end unit of work condition occurred.]],numRepliesOwedMe=0,numRepliesOwedOthers=0,seconds since begin=0,seconds left=10,XAServerResourceInfo[BEADB2]=(ServerResourceInfo[BEADB2]=(state=rolledback,assigned=examplesServer),xar=BEADB2,re-Registered = false),SCInfo[examples+examplesServer]=(state=rolledback),properties=({weblogic.transaction.name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.Bi
gDecimal)], ISOLATION LEVEL=4}),local properties=({modifiedListeners=[weblogic.ejb20.internal.TxManager$TxListener@eed1b8]}),OwnerTransactionManager=ServerTM[ServerCoordinatorDescriptor=(CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+, XAResources={},NonXAResources={})],CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+): weblogic.jdbc.base.BaseBatchUpdateException: [BEA][DB2 JDBC Driver]Abnormal end unit of work condition occurred.
     at weblogic.jdbc.db2.DB2ImplStatement.executeBatch(Unknown Source)
     at weblogic.jdbc.base.BaseStatement.commonExecute(Unknown Source)
     at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:178)
--------------- nested within: ------------------
weblogic.utils.NestedRuntimeException: Error writing from beforeCompletion - with nested exception:
[weblogic.jdbc.base.BaseBatchUpdateException: [BEA][DB2 JDBC Driver]Abnormal end unit of work condition occurred.]
     at weblogic.ejb20.internal.TxManager$TxListener.beforeCompletion(TxManager.java:673)
     at weblogic.transaction.internal.ServerSCInfo.callBeforeCompletions(ServerSCInfo.java:1010)
     at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:178)
--------------- nested within: ------------------
weblogic.transaction.RollbackException: Unexpected exception in beforeCompletion: sync=weblogic.ejb20.internal.TxManager$TxListener@eed1b8
Error writing from beforeCompletion - with nested exception:
[weblogic.utils.NestedRuntimeException: Error writing from beforeCompletion - with nested exception:
[weblogic.jdbc.base.BaseBatchUpdateException: [BEA][DB2 JDBC Driver]Abnormal end unit of work condition occurred.]]
     at weblogic.transaction.internal.TransactionImpl.throwRollbackException(TransactionImpl.java:1683)
     at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:178)
.>
222222222222222
Second case is where timeout in WebLogic occurred (I think) which leads to something messing up the connection pool
####<30/09/2005 10:56:24 AM EST> <Warning> <Common> <ATP-NL2-RS3> <examplesServer> <ExecuteThread: '12' for queue: 'weblogic.kernel.Default'> <<anonymous>> <BEA1-22BE56A9177C58E3D95B> <BEA-000631> <Unknown resource "weblogic.jdbc.common.internal.ConnectionEnv@1551d57" being released to pool "BEADB2". Printing out current pool contents.>
####<30/09/2005 10:56:24 AM EST> <Warning> <Common> <ATP-NL2-RS3> <examplesServer> <ExecuteThread: '12' for queue: 'weblogic.kernel.Default'> <<anonymous>> <> <BEA-000631> <Unknown resource "weblogic.jdbc.common.internal.ConnectionEnv@1551d57" being released to pool "BEADB2". Printing out current pool contents.>
####<30/09/2005 10:56:24 AM EST> <Warning> <Common> <ATP-NL2-RS3> <examplesServer> <ExecuteThread: '12' for queue: 'weblogic.kernel.Default'> <<anonymous>> <> <BEA-000631> <Unknown resource "weblogic.jdbc.common.internal.ConnectionEnv@f95d4a" being released to pool "BEADB2". Printing out current pool contents.>
####<30/09/2005 10:56:24 AM EST> <Error> <EJB> <ATP-NL2-RS3> <examplesServer> <ExecuteThread: '14' for queue: 'weblogic.kernel.Default'> <<anonymous>> <> <BEA-010026> <Exception occurred during commit of transaction Name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)],Xid=BEA1-22BD56A9177C58E3D95B(18185360),Status=Rolled back. [Reason=weblogic.transaction.internal.TimedOutException: Transaction timed out after 8 seconds
Name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)],Xid=BEA1-22BD56A9177C58E3D95B(18185360),Status=Active (PrePreparing),numRepliesOwedMe=0,numRepliesOwedOthers=0,seconds since begin=8,seconds left=10,activeThread=Thread[ExecuteThread: '14' for queue: 'weblogic.kernel.Default',5,Thread Group for Queue: 'weblogic.kernel.Default'],XAServerResourceInfo[BEADB2]=(ServerResourceInfo[BEADB2]=(state=started,assigned=none),xar=BEADB2,re-Registered = false),SCIn
fo[examples+examplesServer]=(state=pre-preparing),properties=({weblogic.transaction.name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)], ISOLATION LEVEL=4}),local properties=({modifiedListeners=[weblogic.ejb20.internal.TxManager$TxListener@1f2a681], weblogic.jdbc.jta.BEADB2=weblogic.jdbc.wrapper.TxInfo@1a4ef37}),OwnerTransactionManager=ServerTM[ServerCoordinatorDescriptor=(CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+, XAResources={},
NonXAResources={})],CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+)],numRepliesOwedMe=0,numRepliesOwedOthers=0,seconds since begin=9,seconds left=9,XAServerResourceInfo[BEADB2]=(ServerResourceInfo[BEADB2]=(state=rolledback,assigned=examplesServer),xar=BEADB2,re-Registered = false),SCInfo[examples+examplesServer]=(state=rolledback),properties=({weblogic.transaction.name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)], ISOLATION LEVEL=4})
,local properties=({modifiedListeners=[]}),OwnerTransactionManager=ServerTM[ServerCoordinatorDescriptor=(CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+, XAResources={},NonXAResources={})],CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+): weblogic.transaction.internal.TimedOutException: Transaction timed out after 8 seconds
Name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)],Xid=BEA1-22BD56A9177C58E3D95B(18185360),Status=Active (PrePreparing),numRepliesOwedMe=0,numRepliesOwedOthers=0,seconds since begin=8,seconds left=10,activeThread=Thread[ExecuteThread: '14' for queue: 'weblogic.kernel.Default',5,Thread Group for Queue: 'weblogic.kernel.Default'],XAServerResourceInfo[BEADB2]=(ServerResourceInfo[BEADB2]=(state=started,assigned=none),xar=BEADB2,re-Registered = false),SCIn
fo[examples+examplesServer]=(state=pre-preparing),properties=({weblogic.transaction.name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)], ISOLATION LEVEL=4}),local properties=({modifiedListeners=[weblogic.ejb20.internal.TxManager$TxListener@1f2a681], weblogic.jdbc.jta.BEADB2=weblogic.jdbc.wrapper.TxInfo@1a4ef37}),OwnerTransactionManager=ServerTM[ServerCoordinatorDescriptor=(CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+, XAResources={},
NonXAResources={})],CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+)
     at weblogic.transaction.internal.ServerTransactionImpl.wakeUp(ServerTransactionImpl.java:1614)
     at weblogic.transaction.internal.ServerTransactionManagerImpl.processTimedOutTransactions(ServerTransactionManagerImpl.java:1117)
     at weblogic.transaction.internal.TransactionManagerImpl.wakeUp(TransactionManagerImpl.java:1881)
     at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:178)
--------------- nested within: ------------------
weblogic.transaction.RollbackException: Transaction timed out after 8 seconds
Name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)],Xid=BEA1-22BD56A9177C58E3D95B(18185360),Status=Active (PrePreparing),numRepliesOwedMe=0,numRepliesOwedOthers=0,seconds since begin=8,seconds left=10,activeThread=Thread[ExecuteThread: '14' for queue: 'weblogic.kernel.Default',5,Thread Group for Queue: 'weblogic.kernel.Default'],XAServerResourceInfo[BEADB2]=(ServerResourceInfo[BEADB2]=(state=started,assigned=none),xar=BEADB2,re-Registered = false),SCIn
fo[examples+examplesServer]=(state=pre-preparing),properties=({weblogic.transaction.name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)], ISOLATION LEVEL=4}),local properties=({modifiedListeners=[weblogic.ejb20.internal.TxManager$TxListener@1f2a681], weblogic.jdbc.jta.BEADB2=weblogic.jdbc.wrapper.TxInfo@1a4ef37}),OwnerTransactionManager=ServerTM[ServerCoordinatorDescriptor=(CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+, XAResources={},
NonXAResources={})],CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+) - with nested exception:
[weblogic.transaction.internal.TimedOutException: Transaction timed out after 8 seconds
Name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)],Xid=BEA1-22BD56A9177C58E3D95B(18185360),Status=Active (PrePreparing),numRepliesOwedMe=0,numRepliesOwedOthers=0,seconds since begin=8,seconds left=10,activeThread=Thread[ExecuteThread: '14' for queue: 'weblogic.kernel.Default',5,Thread Group for Queue: 'weblogic.kernel.Default'],XAServerResourceInfo[BEADB2]=(ServerResourceInfo[BEADB2]=(state=started,assigned=none),xar=BEADB2,re-Registered = false),SCIn
fo[examples+examplesServer]=(state=pre-preparing),properties=({weblogic.transaction.name=[EJB db2transferapp.TransferBean.doTransfer(java.lang.String,java.lang.String,java.math.BigDecimal)], ISOLATION LEVEL=4}),local properties=({modifiedListeners=[weblogic.ejb20.internal.TxManager$TxListener@1f2a681], weblogic.jdbc.jta.BEADB2=weblogic.jdbc.wrapper.TxInfo@1a4ef37}),OwnerTransactionManager=ServerTM[ServerCoordinatorDescriptor=(CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+, XAResources={},
NonXAResources={})],CoordinatorURL=examplesServer+203.143.168.208:7001+examples+t3+)]
     at weblogic.transaction.internal.TransactionImpl.throwRollbackException(TransactionImpl.java:1683)
     at weblogic.transaction.internal.ServerTransactionImpl.internalCommit(ServerTransactionImpl.java:325)
     at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:178)
.>
Once start getting those things released to pool the application falls apart. Shortly afterwards it loses all connections to DB2 (and DB2 may be left with some locks on the table that have to be cleared).
It isn't DB2 specific, if needed I can supply similar data for MSSQL server (BEA or MS drivers)

Setting transaction isolation levels in WAS5

I think I'm missing something pretty easy. How can I set the isolation
levels for the containter managed transactions on my beans?
Specifically, I want to set soem lookup methods on my Sessions beans
to TRANSACTION_REPEATABLE_READ. I've already put the
container-transaction blocks in my ejb-jar.xml
Does Websphere 5 have something akin to WebLogic's
weblogic-ejb-jar.xml where you can set additional parameters like
this? Do I have to use a tool like WSAD to specify this? The AAT
doesn't seem to have this option.
Thanks,
James Lynn

Hi Slava, Ryan,
We haven't looked at 8.1 yet since our release cycle wouldn't allow us
to move to 8.1 until at least June anyway, but even if the problems was
fixed there it took BEA support more than 6 months (I opened the case on
Sep 23 2002 and only this week I got the patch that I haven't even tried
to test to see if it works) to issue a patch for such a small problem.
The server would just check if the Oracle XA driver was being used and
no matter what version would just throw an exception if you try to set
the transaction isolation level saying that the feature in the Oracle
8.1.7 driver was broken... (although you might be using 9.x or even a
pre-8.1.7 driver)...
So this is about it.
And Slava, I've tried pushing a case harder only to end up with BEA
support trying to convince me that I was misinterpreting the JDBC spec
when it was not true, so I just gave up. The main goal of BEA support in
all of our experience has been that they don't try to solve the cases
but close them.
That's my and some of my colleagues personal views anyway, you don't
have to share them.
Regards,
Dejan
Slava Imeshev wrote:
Hi Deyan,
Sorry for the delay. Could you give us more details about CR090104?
I've got some feedback in XA area, not sure if it was a related case.
Also, I've never had any problems with weblogic CCE, so you may want
to push your case a little harder.
As per the bold statement - the initial question was about functionality
available in weblogic but not available in websphere - it can't be more
bold :)
Regards,
Slava Imeshev
"Deyan D. Bektchiev" <[email protected]> wrote in message
news:[email protected]...
This is a very bold statement Slava, considering that with Oracle XA
driver you cannot even set the transaction isolation level because of a
Weblogic bug (CR090104 that has been open for more than 6 months
already)...
Dejan
Slava Imeshev wrote:
Hi James,
"James F'jord Lynn" <[email protected]> wrote in message
news:[email protected]...
I think I'm missing something pretty easy. How can I set the isolation
levels for the containter managed transactions on my beans?
Specifically, I want to set soem lookup methods on my Sessions beans
to TRANSACTION_REPEATABLE_READ. I've already put the
container-transaction blocks in my ejb-jar.xml
Does Websphere 5 have something akin to WebLogic's
weblogic-ejb-jar.xml where you can set additional parameters like
this? Do I have to use a tool like WSAD to specify this? The AAT
doesn't seem to have this option.
My guess here is that it's a signal that this is a last chance
for you to abandon WebSphere and return back to WebLogic's
safe harbor.
Regards,
Slava Imeshev

Regarding Transaction Isolation Level

We talk about query and update constent problem again. even I don't take it as problem.
I can see this in SAP notes or SAP help:
JDBC Sender Adapter...
· The UPDATE statement must alter exactly those data records that have been selected by the SELECT statement. You can ensure this is the case by using an identical WHERE clause. (See Processing Parameters, SQL Statement for Query, and SQL Statement for Update below).
· Processing can only be performed correctly when the Transaction Isolation Level is set to repeatable_read or serializable.
If I set transaction isolation level as default, then how can I make sure ' default' is repeatable_read or serializable?
Our DB is Informix.

Hey
Please go through the below blog and see if it helps
/people/yining.mao/blog/2006/09/13/tips-and-tutorial-for-sender-jdbc-adapter
Thanks
Aamir

Setting transaction isolation level rises ORA-02089 error

Hello
We have configured a distributed transaction in our application server and
we are using openjpa 1.2.1 and Glassfish application server and Oracle 11g as DB server. Although the default behavior of transaction locking must be optimistic,
it seems that pessimistic locking has been happened.
It is found that Row Lock contention happens in a specific table.
This is the exception :
java.sql.SQLException: ORA-02049: timeout: distributed transaction waiting for lock
Already all the following properties have been set for openjpa.
1. <persistence-unit name="JPXA" transation-type="JTA">
2. <property name="openjpa.TransactionMode" value="managed"/>
You can try a plug-in string to lookup the TM in JNDI (the value is the JNDI name of GlassFish TM as per Google search)
3. <property name="openjpa.ManagedRuntime"
value="jndi(TransactionManagerName=java:appserver/TransactionManager)"/>
Following searching about this locking problem, we found that we should add two more properties for openjpa as listed below.
<property name="openjpa.LockManager" value="version" />
<property name="openjpa.jdbc.TransactionIsolation" value="read-committed" />
but this time by setting the transaction isolation level, we have got another error: org.apache.openjpa.persistence.PersistenceException: ORA-02089: COMMIT is not allowed in a subordinate session.
Thanks for any help.
Regards,
Sargol

Hello
We have configured a distributed transaction in our application server and
we are using openjpa 1.2.1 and Glassfish application server and Oracle 11g as DB server. Although the default behavior of transaction locking must be optimistic,
it seems that pessimistic locking has been happened.
It is found that Row Lock contention happens in a specific table.
This is the exception :
java.sql.SQLException: ORA-02049: timeout: distributed transaction waiting for lock
Already all the following properties have been set for openjpa.
1. <persistence-unit name="JPXA" transation-type="JTA">
2. <property name="openjpa.TransactionMode" value="managed"/>
You can try a plug-in string to lookup the TM in JNDI (the value is the JNDI name of GlassFish TM as per Google search)
3. <property name="openjpa.ManagedRuntime"
value="jndi(TransactionManagerName=java:appserver/TransactionManager)"/>
Following searching about this locking problem, we found that we should add two more properties for openjpa as listed below.
<property name="openjpa.LockManager" value="version" />
<property name="openjpa.jdbc.TransactionIsolation" value="read-committed" />
but this time by setting the transaction isolation level, we have got another error: org.apache.openjpa.persistence.PersistenceException: ORA-02089: COMMIT is not allowed in a subordinate session.
Thanks for any help.
Regards,
Sargol

Setting transaction isolation level for jDriver Oracle/XA

edocs (http://e-docs.bea.com/wls/docs70/oracle/trxjdbcx.html#1080746) states that,
if using jDriver for Oracle/XA you can not set the transaction isolation level
for a
transaction and that 'Transactions use the transaction isolation level set on
the connection
or the default transaction isolation level for the database'. Does this mean that
you shouldn't try to set it programatically (fair enough) or that you can't set
it in the weblogic deployment descriptor either? Also anybody got any idea what
the default is likely to be if you are using
an Oracle 9iR2 database?

Ian,
The default for Oracle (any version) is ReadCommitted. The only other
isolation level Oracle supports is Serializable but it's implemented in
such a way that you will be allowed to continue until commit time and
only then you might get an exception stating the the access for that
transaction could not be serialized.
I don't know for the jDriver but if you use the Oracle Thin XA driver
even if you set the isolation level in your descriptor you will get an
exception from Weblogic. It is a Weblogic bug and you can contact
[email protected] to get a patch.
Regards,
Dejan
IJ wrote:
edocs (http://e-docs.bea.com/wls/docs70/oracle/trxjdbcx.html#1080746) states that,
if using jDriver for Oracle/XA you can not set the transaction isolation level
for a
transaction and that 'Transactions use the transaction isolation level set on
the connection
or the default transaction isolation level for the database'. Does this mean that
you shouldn't try to set it programatically (fair enough) or that you can't set
it in the weblogic deployment descriptor either? Also anybody got any idea what
the default is likely to be if you are using
an Oracle 9iR2 database?

Using transaction-isolation tag

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