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From "Lin Sun" <>
Subject RE: daytrader with Tranql Oracle XA resource adapter
Date Fri, 07 Jul 2006 15:25:26 GMT
Hi there,

Thanks for the pointer!  IIUC, if the application uses connection.commit,
tranql will translate that as setautocommit(true) when the
commitBeforeAutoCommit is set to false.   I believe this is what I have in
my environment.

However, I still don't understand why it makes such a big difference for
Oracle.  I have loaded daytrader on another J2EE application server
(WebSphere Application Server) and found out the same order committed to the
oracle database right away.  With that, I would not categorize it as one of
the problematic drivers you mentioned before.

Since derby and db2 XA adapter don't have this "delayed committing" problem
at all, I compared the two Tranql vendors' code with the Oracle vendor code.
Basically the vendor code contains the vendor specific MCF class that is
created based on the datasource from the vendor (for example,
OracleXADataSource).  The MCF also sets/gets the datasource's different
properties (like databasename, username, password, servername, etc.).  I
still don't get much clue as to why Oracle is special with Tranql.

I think what I'll do is to come up with a simple application that can be
loaded into Eclipse and step into the connection.commit() code from Eclipse.
Too bad that I haven't figured out how to get daytrader running from

Time to study the new plugin Sachin puts out.:-)


-----Original Message-----
From: Mario Rübsam [] 
Sent: Thursday, July 06, 2006 2:37 PM
Subject: Re: daytrader with Tranql Oracle XA resource adapter

Lin Sun wrote:
> Hi there,
> Do you know how to log the commits on the oracle side?  I 'll be happy to
> check that out if I know how to do it.

I don't have a clue about the Oracle tools. But there must be some admin
tool to show the stats of the server, the connections, threads, ...
There is normally a transaction counter in these tools. Another way to find
it out is to look into the driver itself and figure out what is going on
in the setAutoCommit() method. But this is not legal in every country for
closed source interfaces.

> I posted another note yesterday.   The application was not using
> Instead connection.commit() is being used.

That is correct, but to commit the local transaction TranQL use the
setAutoCommit(true); method, so if the JDBC driver is spec compliant the
transaction must be commited ... so far the theory, in the real world
some of the drivers don't do it for performance or whatever reasons.

There was already a discussion about this problem here:


> Lin
> -----Original Message-----
> From: Mario Rübsam [] 
> Sent: Wednesday, July 05, 2006 4:59 PM
> To:
> Subject: Re: daytrader with Tranql Oracle XA resource adapter
> I don't have experience with the Oracle Adapter. Can you log the commits
> the Oracle side to see if any commits come through? I had a similar
> with MaxDB and it seems that the transactions are not closed because the
> JDBC driver for MaxDB did no commit on the connection if the AutoCommit
> switched from false to true. The JDBC spec says if the value changed the
> connection must be commited but the driver does not. Thats why I use
> CommitBeforeAutCommit now.
> Can you try to use the generic adapter to connect to Oracle and see if it
> happens also?
> Thanks,
> Mario
> Lin Sun wrote:
>> Hi there,
>> Thanks - I remember seeing your posting on CommitBeforeAutCommit setting
> in
>> the generic adapter.    The CommitBeforeAutCommit setting is not avail in
>> the Oracle XA resource adapter.  
>> Lin
>> -----Original Message-----
>> From: Mario Rübsam [] 
>> Sent: Thursday, June 29, 2006 4:56 PM
>> To:
>> Subject: Re: daytrader with Tranql Oracle XA resource adapter
>> Hi,
>> the CommitBeforeAutCommit setting in the generic adapter call
>> a commit on the local connection before it calls setAutoCommit(true).
>> Some JDBC drivers act not like specified in JDBC and don't call
>> a commit when the AutoCommit value changes with setAutoCommit(true)
>> so CommitBeforeAutCommit is a workaround to get the transaction
>> commited on these drivers (MySQL, MaxDB, PostgreSQL in some cases).
>> I don't know about the XA driver and Oracle but it could be a similar
>> problem.
>> -Mario
>> Lin Sun wrote:
>>> Hi there,
>>> I have been playing with the daytrader with Tranql Oracle XA resource
>>> adapter (tranql-connector-oracle-xa-1.1.rar).  After I tweaked the
>>> plan a bit and I am able to get daytrader running well with oracle!
>>> One thing I noticed is that if I perform any trading activities as a
>>> user (say uid:1, account_id 50), I get the message that my order has
>>> been completed almost immediately.  However, the order isn't committed
>>> into the oracle database until quite a while.  I don't know the exact
>>> timing but seems to be over 20-30 minutes.
>>> Here is what I did to check if the order is recorded in the database:
>>> Select * from orderejb where account_id=50;
>>> If the order is committed into the database, I would expect a row that
>>> represents my previous order to be returned as the output of the sql
>>> command.
>>> If I run the same scenario with db2 or derby, I can see my order
>>> recorded in the orderejb table immediately.
>>> I looked at the tranql oracle vendor code but I didn't see anywhere
>>> specifying the commit timing thing.  The generic resource adapter does
>>> offer an param called CommitBeforeAutCommit and by setting it to true
>>> would force the commit to happen immediately.   Can someone shed some
>>> light on this?
>>> Thanks, Lin

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