Re: Object serialization problem - .NET (Core and Framework) Discussion Boards

Dimpal1701-Sep-11 4:38

1-Sep-11 4:38

During batch job processing i found lots of Deadlock occurance in logfile. Is it code issue or Database setting issue. I have 2-thread two-core CPU.

I am running this batch with 2-threads and maximum batch-size=1000.
In database setting for initrans=5 and maxtrans=250.

It causes when I run batch process with hundreds of thousands records. Please help me here.

LogFile error

General Level="High" Type="Custom" Severity="Notice" TimeStamp="2011-08-30 09:54:45" Message="WD: FAILED: An exception was caught during the execution of an action query: ORA-00060: deadlock detected while waiting for resource
. Check InnerException, QueryExecuted and Parameters of this exception to examine the cause of this exception. ---

Re: Deadlock issue in batch processing

Wendelius3-Sep-11 4:35

Wendelius

3-Sep-11 4:35

The deadlock occurs when two or more sessions wait for the locks that are held by the opposite session. For more info,: http://www.oracle-base.com/articles/misc/Deadlocks.php[^].

Deadlock is a code issue. The best way to avoid deadlock is to make the changes to the tables always in the same order.

If you run a batch modifications, one possibility could be to lock the entire table before the batch starts. However the downside is that no-one can make modifications to this table while your batch is running.

The need to optimize rises from a bad design.My articles[^]

Re: Deadlock issue in batch processing

jschell3-Sep-11 10:24

jschell

3-Sep-11 10:24

Dimpal170 wrote:
I am running this batch with 2-threads and maximum batch-size=1000.

In database setting for initrans=5 and maxtrans=250.

It causes when I run batch process with hundreds of thousands records. Please help me here.

Presumably what you mean is the following.

You need to process (insert/update) hundreds of thousands of records.
You are batching with a maximum of 1000 updates/inserts in one batch (where 1000 is a chunk of the total amount of processing to be done.)
You are using two threads each of which does its own batch (1000 at a time.)

If you are not doing that then please explain what it is that you are doing.

Are you processing data while doing the batch or doing nothing but the SQL?

Have you considered using the database import tool?

Saving FlowDocument to XPS causes viewer to go blank

Geron31-Aug-11 22:17

Geron

31-Aug-11 22:17

My XAML for the viewer window looks something like this:

HTML

<Window>
  <DockPanel LastChildFill="True">
    <StackPanel DockPanel.Dock="Bottom" Orientation="Horizontal">
      <Button Width="100" Height="25" Click="Save_Click">Save</Button>
    </StackPanel>
    <FlowDocumentScrollViewer DockPanel.Dock="Top" VerticalScrollBarVisibility="Auto">
      <FlowDocument x:Name="flowDoc" Background="White" PagePadding="5">
        <BlockUIContainer>
          <!--... Data bound UI stuff-->
        </BlockUIContainer>
      </FlowDocument>
    </FlowDocumentScrollViewer>
  </DockPanel>
</Window>

The Save_Click handler looks like this:

private void Save_Click(object sender, RoutedEventArgs e)
{
  SaveFileDialog dialog = new SaveFileDialog();
  dialog.DefaultExt = "xps";
  dialog.Filter = "XPS Document (*.xps)|*.xps";
  dialog.OverwritePrompt = true;

  if (dialog.ShowDialog() == true)
  {
    using (Package package = Package.Open(dialog.FileName, FileMode.Create, FileAccess.ReadWrite))
    {
      using (XpsDocument xpsDoc = new XpsDocument(package, CompressionOption.Maximum))
      {
        XpsSerializationManager rsm = new XpsSerializationManager(new XpsPackagingPolicy(xpsDoc), false);
        DocumentPaginator paginator = ((IDocumentPaginatorSource)flowDoc).DocumentPaginator;
        rsm.SaveAsXaml(paginator);
        rsm.Commit();
      }
    }
  }
}

Now when I click the "Save" button and enter a file name. The document is saved to a XPS file and all is good. HOWEVER, the FlowDocumentScrollViewer goes completely blank once the file is written to disk.

Is there any way to prevent this behaviour? I've tried some code to clone the FlowDocument via the use of TextRange etc. But the problem with this approach is that the UI elements isnt included in the cloned document, only regular text elements.

Re: Saving FlowDocument to XPS causes viewer to go blank [modified]

Pradeep Shukla6-Sep-11 17:46

Pradeep Shukla

6-Sep-11 17:46

You can try using this with additional margin & thickness

FlowDocumentScrollViewer Margin="10" BorderBrush="Black" BorderThickness="1"

I found one more article, it may be of some help:

http://petterisbetter.com/michael/index.php/2008/09/23/background-printing-with-flowdocumentscr[^]

modified on Wednesday, September 7, 2011 12:21 AM

Object serialization problem

columbos1492730-Aug-11 23:58

columbos14927

30-Aug-11 23:58

Hello,
I have an Serializable object "System configuration" when my application starts up i am preforming deserialization from XML file to an "System configuration" object and its works fine.

But when i try to serialize the object to the XML file i get the

next Exception:
"There was an error generating "the XML document"

Inner Exception message:
"A circular reference was detected while serializing an object of type Byte description"

System configuration object has a byte description oibject.

Any one has an idea what is the problem?

Thanks in advance...

Re: Object serialization problem

Richard Andrew x6431-Aug-11 6:54

Richard Andrew x64

31-Aug-11 6:54

One thing I can think of is if a child object holds a reference to its parent object, that represents a circular reference. It can't serialize such things because it would lead to infinite recursion.

The difficult we do right away...
...the impossible takes slightly longer.

Re: Object serialization problem

Columbus-MCSD4-Sep-11 17:53

Columbus-MCSD

4-Sep-11 17:53

you need to show some code for a better answer

anyway, here's how to serialize xml

class myClass(){/*define class*/}

void SerializeToXML(myClass object)
 {
   XmlSerializer serializer = new XmlSerializer(typeof(myClass));
   TextWriter textWriter = new StreamWriter(/*filename here*/);
   serializer.Serialize(textWriter, object);
   textWriter.Close();
 }

As you saw in your app, the XMLSerializer also doesn't support circular references. If you need this kind of flexibility, you should consider binary serialization.

Here's how you can serialize to binary

void SerializeToBinary(myClass object, MemoryStream stream)
{
    stream.Seek(0, System.IO.SeekOrigin.Begin); 
    BinaryFormatter formatter = new BinaryFormatter();
    formatter.Serialize(stream, object);
}

Use XmlTextWriter to manually create an XML file, and use XmlTextWriter.WriteBase64 to write your binary data into the file. Make sure you add a "length" attribute.

here's how to deserialize the binary back into an object

First make an XmlTextReader, navigate to the Element you wrote and create a MemoryStream

then create a byte[array] and put the data in it

xr.MoveToAttribute("length");
xr.ReadAttributeValue();
int length = Int32.Parse(xr.Value);
byte[] data = new byte[length];
xr.ReadBase64(data, 0, length);
stream.Write(data, 0, length);

now you can deserialize your object

stream.Seek(0, System.IO.SeekOrigin.Begin);
IFormatter formatter = new BinaryFormatter();
myClass object = (myClass)formatter.Deserialize(stream);

I am getting this kind of error,pls help

jitendra rajbher30-Aug-11 23:43

jitendra rajbher

30-Aug-11 23:43

See the end of this message for details on invoking
just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************
System.Data.OleDb.OleDbException: Could not find file 'D:\Documents and Settings\Raj Computer\Local Settings\Apps\2.0\8JC0578H.AN4\N27XQ98C.YR9\abcd..tion_6cdeed2b4dc164ad_0001.0000_dd2b28ab3a97d826\Database2.mdb'.
at System.Data.OleDb.OleDbConnectionInternal..ctor(OleDbConnectionString constr, OleDbConnection connection)
at System.Data.OleDb.OleDbConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningObject)
at System.Data.ProviderBase.DbConnectionFactory.CreateNonPooledConnection(DbConnection owningConnection, DbConnectionPoolGroup poolGroup)
at System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection)
at System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory)
at System.Data.OleDb.OleDbConnection.Open()
at WindowsApplication1.Form1.Form1_Load(Object sender, EventArgs e)
at System.EventHandler.Invoke(Object sender, EventArgs e)
at System.Windows.Forms.Form.OnLoad(EventArgs e)
at System.Windows.Forms.Form.OnCreateControl()
at System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
at System.Windows.Forms.Control.CreateControl()
at System.Windows.Forms.Control.WmShowWindow(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
at System.Windows.Forms.ContainerControl.WndProc(Message& m)
at System.Windows.Forms.Form.WmShowWindow(Message& m)
at System.Windows.Forms.Form.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

************** Loaded Assemblies **************
mscorlib
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)
CodeBase: file:///D:/WINDOWS/Microsoft.NET/Framework/v2.0.50727/mscorlib.dll
----------------------------------------
abcd
Assembly Version: 1.0.0.0
Win32 Version: 1.0.0.0
CodeBase: file:///D:/Documents%20and%20Settings/Raj%20Computer/Local%20Settings/Apps/2.0/8JC0578H.AN4/N27XQ98C.YR9/abcd..tion_6cdeed2b4dc164ad_0001.0000_dd2b28ab3a97d826/abcd.exe
----------------------------------------
Microsoft.VisualBasic
Assembly Version: 8.0.0.0
Win32 Version: 8.0.50727.3053 (netfxsp.050727-3000)
CodeBase: file:///D:/WINDOWS/assembly/GAC_MSIL/Microsoft.VisualBasic/8.0.0.0__b03f5f7f11d50a3a/Microsoft.VisualBasic.dll
----------------------------------------
System
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)
CodeBase: file:///D:/WINDOWS/assembly/GAC_MSIL/System/2.0.0.0__b77a5c561934e089/System.dll
----------------------------------------
System.Windows.Forms
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)
CodeBase: file:///D:/WINDOWS/assembly/GAC_MSIL/System.Windows.Forms/2.0.0.0__b77a5c561934e089/System.Windows.Forms.dll
----------------------------------------
System.Drawing
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)
CodeBase: file:///D:/WINDOWS/assembly/GAC_MSIL/System.Drawing/2.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll
----------------------------------------
System.Configuration
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)
CodeBase: file:///D:/WINDOWS/assembly/GAC_MSIL/System.Configuration/2.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll
----------------------------------------
System.Xml
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)
CodeBase: file:///D:/WINDOWS/assembly/GAC_MSIL/System.Xml/2.0.0.0__b77a5c561934e089/System.Xml.dll
----------------------------------------
System.Runtime.Remoting
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)
CodeBase: file:///D:/WINDOWS/assembly/GAC_MSIL/System.Runtime.Remoting/2.0.0.0__b77a5c561934e089/System.Runtime.Remoting.dll
----------------------------------------
System.Data
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)
CodeBase: file:///D:/WINDOWS/assembly/GAC_32/System.Data/2.0.0.0__b77a5c561934e089/System.Data.dll
----------------------------------------
System.Transactions
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)
CodeBase: file:///D:/WINDOWS/assembly/GAC_32/System.Transactions/2.0.0.0__b77a5c561934e089/System.Transactions.dll
----------------------------------------

************** JIT Debugging **************
To enable just-in-time (JIT) debugging, the .config file for this
application or computer (machine.config) must have the
jitDebugging value set in the system.windows.forms section.
The application must also be compiled with debugging
enabled.

For example:

<configuration>
<system.windows.forms jitdebugging="true">

When JIT debugging is enabled, any unhandled exception
will be sent to the JIT debugger registered on the computer
rather than be handled by this dialog box.

Re: I am getting this kind of error,pls help

Dave Kreskowiak31-Aug-11 2:09

Dave Kreskowiak

31-Aug-11 2:09

Basically, it's telling you it can't find your database file, Database2.mdb.

Apparently you're using ClickOnce deployment and your connection string is eithwe wrong or your database file didn't get deployed with your app for some reason.

Read these[^] for some tips on resolving the issue.

A guide to posting questions on CodeProject[^]

Dave Kreskowiak

Re: I am getting this kind of error,pls help

jitendra rajbher31-Aug-11 3:43

jitendra rajbher

31-Aug-11 3:43

wat is the procedure for it can u tell me about this

Re: I am getting this kind of error,pls help

Shameel31-Aug-11 4:19

Shameel

31-Aug-11 4:19

jitendra rajbher wrote:
wat is the procedure for it can u tell me about this

Did you at least care to click the link that Dave posted?

Thanks,but I saw that code but i am not able to see may data

jitendra rajbher31-Aug-11 20:47

jitendra rajbher

31-Aug-11 20:47

ya, i have seen and used in click once but by using that my data is not been showing in the data base,all the procedure is working but i am not able to see the data where it is been store

Re: I am getting this kind of error,pls help

Dave Kreskowiak31-Aug-11 5:40

Dave Kreskowiak

31-Aug-11 5:40

I already told you to start reading the links I posted. I can't tell you the procedure to fix your problem because there are many different causes of it and YOU have to do the research into which one you're facing.

A guide to posting questions on CodeProject[^]

Dave Kreskowiak

In VB .NET how do we get the new row ID number in an access database table BEFORE inserting the new row?

aeskan30-Aug-11 4:12

aeskan

30-Aug-11 4:12

I'm programming with VB .NET 2010 and using a Microsoft Access Database file which is bound to my project as a Dataset. Now I want to know: BEFORE inserting a new row into my dataset table what will be the new ID number, or totally is it possible to know?

Surely you know the autonumber ID of a table is different with row count number, for there may be deleted rows between the table rows. Like the following example:

Row 0: ID=1
Row 1: ID=2
Row 2: ID=4 (ID number 3 is deleted)
Row 3: ID=5
Row 4: ID=9 (ID numbers 6,7,8 are deleted)

Now how do we know what ID number of Row 5 will be before inserting the new row? Perhaps ID numbers 10 and 11 are either deleted or not, so it may be 10, may be 11 or 12 or whatever! Is there a way to know it BEFORE adding or inserting the new row into the table?

Thank you beforehand.

Re: In VB .NET how do we get the new row ID number in an access database table BEFORE inserting the new row?

Pete O'Hanlon30-Aug-11 4:17

Pete O'Hanlon

30-Aug-11 4:17

There is no way to know beforehand if you are using a standard identity value. If you need to know this beforehand, you are either going to have to generate the value yourself, or use something like a GUID instead - which you can assign in your code.

Forgive your enemies - it messes with their heads

My blog | My articles | MoXAML PowerToys | Mole 2010 - debugging made easier - my favourite utility

Re: In VB .NET how do we get the new row ID number in an access database table BEFORE inserting the new row?

aeskan30-Aug-11 9:38

aeskan

30-Aug-11 9:38

Thank you Pete.

Re: In VB .NET how do we get the new row ID number in an access database table BEFORE inserting the new row?

Jitheshvijayan8-Sep-11 20:55

Jitheshvijayan

8-Sep-11 20:55

One way is to store the last ID number in another table and increment it whenever a row is inserted into the table.

Re: In VB .NET how do we get the new row ID number in an access database table BEFORE inserting the new row?

aeskan8-Sep-11 22:40

aeskan

8-Sep-11 22:40

Yes that's the best way, thanks for your remark.

Not able to find Event icon in Property window [modified]

KIDYA29-Aug-11 21:24

KIDYA

29-Aug-11 21:24

Hi Experts,

I am new with VS2008 and not able to find Event icon in Property window or anybody can tell me how i can view all events of particular control.

FYI..I am working with WPF.

Thanks,
Kidya

modified on Tuesday, August 30, 2011 3:31 AM

Re: Not able to find Event icon in Property window

RobCroll30-Aug-11 2:10

RobCroll

30-Aug-11 2:10

At the top of the properties window you should see a tab with a yellow lightning bolt. Click on that and it should display all the available events for the highlighted control

"You get that on the big jobs."

how to implement OOP in vb.net?

visualst29-Aug-11 19:47

visualst

29-Aug-11 19:47

i am a beginner want to learn OOP in VB.Net.
In theory i understand OOP, but i do not understand apply in form of coding.
i need a sample application OOP, suppose the application inventory.Because i want to see how the use of OOP.
so, please help and teach me.
Thank you very much if you wanna help me..

Re: how to implement OOP in vb.net?

Bert Mitton31-Aug-11 3:17

Bert Mitton

31-Aug-11 3:17