Re: Problem with native driver

[cujo@xxxxxxxxxx]

I believe your problem is that stored procedures are not a multi-threaded
resource.  (I don't really know a better way to phrase that, but I am sure
there is one).

You should be able to create a similar problem in a single stand alone
program by doing this:

1) get a conection
2) get 2 statements
3) execute the strored procedure with the first statement (keep the result
set open)
4) execute the stored procedure with the second statement
     ***I would think you are going to get an error about the cursor being
already open at this point

This is because stored procedure resources are job scoped in nature and a
connection also job scoped.  If you try to make multiple concurrent uses of
job scoped resources, you run into problems.

This issue came to may attention while working on allowing greater
concurrency through the Native JDBC driver.  I have worked with some of the
database here and made them aware of it.  They say it is part of the
architecture.  I say it has to change.  So far, I have demonstrated that it
*may* be possible to change the way this works and we will investigate it
further (put another way, it is on my list of things to work on).  There is
little chance that anything would be done here before v4r5 at the earliest.
There is no promise that anything will be done at that time.

Does it sound like I am on track here?  I hate to misread someones issue
and answer the wrong questions. :)

Regards,

Richard D. Dettinger
AS/400 Java Data Access Team

"TRUE! nervous, very, very dreadfully nervous I had been and am; but why
WILL you say that I am mad?
The disease had sharpened my senses, not destroyed, not dulled them. "

- Edgar Allan Poe
"The Tell-Tale Heart"




"DUCRET Gilles (GVA)" <Gilles.DUCRET@lloydsbank.ch> on 02/07/2000 07:48:36
AM

To:   "'JAVA400-L@midrange.com'" <JAVA400-L@midrange.com>
cc:   "DES ROSIERS Daniel (GVA)" <Daniel.DESROSIERS@lloydsbank.ch>, Eric
      Warne/Rochester/IBM@IBMUS, Richard Dettinger/Rochester/IBM@IBMUS,
      MAZY Hervé (GVA) <Herve.MAZY@lloydsbank.ch>
Subject:  Problem with native driver




I have more details on the problem we have with the native driver:

1) We have a java program, running on the as400, and using the native
driver.
This program works perfectly

2) We have some servlets, running on the as400, using the native driver.
The
tested servlet
calls a stored procedure

When we test a servlet from a client, it works.
When we test a servlet from several client, not simultaneously, it works
When we test a servlet from several client simultaneously, we then have no
response.
Empty result set.

It is then impossible to lauch the java program on the as400, we have the
connection problem.

We stop websphere, and then the java program runs correctly on the as400.

Any ideas ?

Here is the description of the received SQLException:

Error code: -901
   Message: SQL system error.

   Class name: com.ibm.db2.jdbc.app.DB2SQLException2

   To string: com.ibm.db2.jdbc.app.DB2SQLException2: SQL system error.

   SQL state: 58004

The error log is attached to this mail

 <<ERROR.LOG>>

Hope you can help us

Gilles


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Title: Problem with native driver

I have more details on the problem we have with the native driver:

1) We have a java program, running on the as400, and using the native driver.
This program works perfectly

2) We have some servlets, running on the as400, using the native driver. The tested servlet
calls a stored procedure

When we test a servlet from a client, it works.
When we test a servlet from several client, not simultaneously, it works
When we test a servlet from several client simultaneously, we then have no response.
Empty result set.

It is then impossible to lauch the java program on the as400, we have the connection problem.

We stop websphere, and then the java program runs correctly on the as400.

Any ideas ?

Here is the description of the received SQLException:

Error code: -901                                                         
   Message: SQL system error.                                               
   Class name: com.ibm.db2.jdbc.app.DB2SQLException2                        
   To string: com.ibm.db2.jdbc.app.DB2SQLException2: SQL system error.      
   SQL state: 58004           

The error log is attached to this mail

<<ERROR.LOG>>

Hope you can help us

Gilles

**********************************************************************
 This email and any files transmitted with it are confidential and 
intended solely for the use of the individual or entity to whom they   
are addressed. If you have received this email in error please notify 
the system manager.

This footnote also confirms that this email message has been swept for
the presence of computer viruses.
**********************************************************************

ERROR.LOG