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i am trying to update my customers table in the northwind database from XML file.
Getting an Wrror
Violation of PRIMARY KEY constraint 'PK_Customers'. Cannot insert duplicate key in object 'dbo.customers'.
i used SqlCommandBuilder to build insert,update and delecte commands.
DataSet DSRead = new DataSet();
DSRead.ReadXml("output.xml");
SqlDataAdapter adapter = new SqlDataAdapter();
adapter.SelectCommand = new SqlCommand (queryString, connection);
SqlCommandBuilder builder = new SqlCommandBuilder(adapter);
connection.Open();
DataSet dataSet = new DataSet();
adapter.Fill(dataSet, tableName);
dataSet = DSRead;
//code to modify data in DataSet here
builder.GetUpdateCommand();
//Without the SqlCommandBuilder this line would fail
adapter.Update(dataSet, tableName);
how can i write CommandBuilder to update, insert and delete.
Thx
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How can i use forgot option in asp.net
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Hi,
Does anyone know how to send parameters through to a crystal report in VS 2008?
I keep on getting this dialog that asks me to enter the discrete value of the parameter.
I would like to send the parameter value through code once the user has selected their filter choice.
This is for Windows Form application and I'm using SQL 2005 Express as the database.
I have googled but cant find a working solution.
Thanks
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There are two of these controls in my windows application.
checking the items in the first one should cause the items in the second control to populate.
At present I use the mouse_leave event on the first control to trigger the event to populate the second control.
Is this the proper event I should use? I do not think the selectedIndex event is the correct one for this purpose either. Any suggestions please?
Thanks
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"Translate" what you have to do in terms of events in your application. Then you'll know what event you have to handle.
SkyWalker
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Hi,
Do not find the relevant event.
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I am newly on in programming in c#.net...Can you help me to take fields from data table separately by c# programming
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I suggest you to chage subject of your question, make it more reasonable if u wanna get answer[^]
I Love T-SQL
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Try reading this:
ADO.NET
or try Google, there are loads of articles on ado.net and c#
Bob
Ashfield Consultants Ltd
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Hi,
I have a VB application with a button.
When I click on that button it must show a windows form application that is made in C#.
How could this be done?
I've heard something about COM object: ComSourceInterfaces
And something about making an interface class file...something like:
[InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]<br />
public interface _InterfaceClient<br />
{<br />
}
Is this the correct way? If so, does anyone have an good example?
Thanks,
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Hi,
i'm working on an programe that reads several items from an MySql Database,
i've got the connection working. but for the last couple of days i've been struggeling.
I want to add items to the database via the use of 2 textbox but i'm cluesless on how to get the query,
i've been going over several pages tough all seem to fix on MMSql 2005 or on the connection string.
Any help would be greatly apriciated
Greetings
Ben
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Any code that attempts to do this at the moment would be useful to see. It will help us point out where you're going wrong.
In the mean time, I suggest you read this great article here[^], specifically the section about parametrised queries. In short, you take the user's input and create a new MySqlParameter object from that information and perform an INSERT statement.
He who makes a beast out of himself gets rid of the pain of being a man
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My coding for adding has been done,
Tought the removing function still does not , and i'm not sure how to finish the following:
string query = "DELETE FROM facturen WHERE Id = " there should be more here
MySql.Data.MySqlClient.MySqlCommand bQuery = new MySql.Data.MySqlClient.MySqlCommand(query, connection);
bQuery.ExecuteNonQuery();
connection.Close();
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Hello everyone,
If all the Finalizer methods of all the used classes in a thread are programmed properly, means native resource are released in Finalizer (e.g. implementing Dispose pattern), no matter how the thread is terminated (normally, by Interrupt or by Abort or by Exit or ...), there should not be any resource leak, right?
thanks in advance,
George
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Any more description please?
regards,
George
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I don't think that Abort gives the chance for a cleanup, unless you call ThreadAbortException. As for the Exit, when an application is terminating, I think the finalizer that are left to execute are not.
Put Trace statements in your Finalizers and Dispose methods to see.
In other words, if a class implements IDisposable, you should always call the Dispose method.
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Thanks Le Centriste,
1.
Le Centriste wrote: In other words, if a class implements IDisposable, you should always call the Dispose method.
We can not alway have chances to call Dispose when unexpcted Abort is called on the thread, right?
2.
So, your point is there will be native resource leak when we call abort?
regards,
George
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Usually, you should catch the ThreadAbortException in your thread. Read the remarks section of the following link:
http://msdn2.microsoft.com/en-us/library/ty8d3wta.aspx[^]
Your thread entry point should have a try/catch block, with special handling for ThreadAbortException.
Quick question: why do you need to call abort on your thread?
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Thanks Le Centriste,
1.
You mean in the exception handler for ThreadAbortException, we should do clean-up things, like release the native resouce, or else there will be resource leak, right?
2.
Le Centriste wrote: Quick question: why do you need to call abort on your thread?
I am afraid others may call Thread.Abort on my thread, so I am asking how to handle properly.
regards,
George
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George_George wrote: You mean in the exception handler for ThreadAbortException, we should do clean-up things, like release the native resouce, or else there will be resource leak, right?
Yes, and if your thread is also prone to block, handle the ThreadInterruptedException also.
George_George wrote: I am afraid others may call Thread.Abort on my thread, so I am asking how to handle properly
That is very good thinking.
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Thanks Le Centriste,
Le Centriste wrote: Yes, and if your thread is also prone to block, handle the ThreadInterruptedException also.
Either Abort or Interrupt is called, the Finalizers are not ensured to be called? I think if they are ensured to be called, we can rely on them to clean-up resources, and leave the body of handlers for Abort/Interrupt exceptions empty.
Any comments?
regards,
George
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As a golden rule, you should always clean up behind you, and not rely on your mother to do it.
Seriously, you could simply use the using statement, as finally blocks are always executed, no matter what. That will free you from having to handle the exceptions and still do the cleanup.
We should not rely on the Finalizers, as they are there as a last defense, and you don't know when they execute. Calling the Dispose method from a finally is a surefire way of cleaning up.
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Thanks Le Centriste,
I am just wondering whether there are any official documents from Microsoft about whether finally block or Finalizer will be ensured to be called, when we call Interrupt or Abort on thethread?
Do you find such documents?
regards,
George
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