Just to update you, I noticed that the nwind.mdb table name was Employees (with an "s") and your BO was mapped without the "s".  Changed this and it still did not work.  45 minutes into it and still can't make your sample work.  Sorry.  I am going to wait until I receive more details about what database I am supposed to connect to.

One other thing I noticed is that this is not a StrataFrame wired web application.  Clearly you can do this, but you may have Session issues, etc. since we wire things up through the ApplicationBasePage and the global.asax.  I noticed that you created your own TestBasePage.cs....this is really not related to the issue, just an observation.

Awaiting further instruction.  Thanks.

Chan,

I am confused as to what your application is trying to do.  You supplied the nwind.mdb database, but your connection string is an SqlDataSourceItem (not Access), so I am not sure what database I am supposed to connect to.  Since your test app is wired to look at an SQL database I am assuming that you have an MDF somewhere that I should be connecting to.  I will look through all of the attached files again, but please advise.  Thank you.

Chan,

For whatever this is worth, we have not changed anything in this regard.  I am willing to bet that you have an old assembly someplace, or something within your environment has changed.  I will look at this, but I find it strange that this would just suddenly "reappear."

Hi

Glad you found a solution.  We will take this post into consideration and look at it from this perspective to see if we can reproduce. 

Hi,

After some further testing, I think I found the root cause of the memory leak. It is actually happen if I have subscribed any BO's events at Page_Load.



As event binding will cause dangling reference to subscriber and publisher object (Web.Page and BO in this case), supposedly it shouldn't not cause any memory leak as garbage collector able to handle it. However, as SF way of web dev, BO is always be stored at session variable, it prevents GC to collect them even though is unused.



My current temporary fix is to unsubscribe all BO events at Page_Unload. It seem works (as I tested using one page). I will ask to change the rest of page and test again.



I am not sure if other SF users notice about this, but I am quite new to .NET and not really realize about this. I hope this could be mentioned at somewhere, at least help document.



Beside, some .NET expert has pointed me to this url which use another approach to prevent event-memory leak. Here is it for your reference if SF is not notice about it yet.



http://blog.codeinreview.com/post/2008/11/27/NET-EVENTS-(Part-3-A-Weak-Solution).aspx



Thank you for your previous effort, I am going to test it again and hope it could be solved. Also, I hope SF suggest/implement any better approach (weakevent for example) so that developer do not required to remember to unsubscribe BO events all the time.



Thank you very much.

Well, this thread is getting a bit ambiguous.  I was just commenting on your Clone comment.  In regards to the core of your issue, are you referring the SqlTransaction error?  The error, which you have already learned, is going to be specific to something that you are doing within your code.  So the questions to work through are:

• When are you creating a transaction?
• Is it possible for the same code to be called at the same time?
• Are the objects in question specific to a session or the application?
• Are you using shared data tables?
• If you turn off transactions do your issues go away?

These are types of things that you need to be asking yourself.  Only you know your exact code and what you have done at this point.  This code is going to be related to your specific application.  So I would begin to work through these questions.

Hi,

Any hint how to troubleshoot on this?



Thank you

Agreed.  The Clone should not cause an issue as it creates a unique instance which is then fully autonomous from the other instance.

Hi,

After further thinking, don't feel loCommand = loCommand.Clone() can cause this problem. hmmm...