Miha
Fri Dec 03 06:00:21 CST 2004
Hi Patrick,
Of course, you need to delete rows from children to master and insert rows
from master to children.
Instead of passing dal as parameter, use dal.GetChanges(DataRowState) to
filter the rows required for the pass, for example, when deleting you will
pass DataRowState.Deleted, when inserting you'll pass DataRowState.Added,
etc.
You need at least two passes, one for Delete and other for Add (Modified
rows doesn't care of Update order).
When the transaction is complete, you'll have to Merge those rows back to
original DataSet.
--
Miha Markic [MVP C#] - RightHand .NET consulting & development
SLODUG - Slovene Developer Users Group
www.rthand.com
"Patrick" <Patrick@discussions.microsoft.com> wrote in message
news:B02A8732-32F7-4016-A948-D9EBEBBBC2F8@microsoft.com...
> Hi Miha,
>
> thanks I tried this before. But it just works, if I switch the updating
> order of my OleDbAdapters:
>
> this.oleDbDataAdapter1.Update(dal);
> this.oleDbDataAdapter2.Update(dal);
> this.oleDbDataAdapter4.Update(dal); no 4
> this.oleDbDataAdapter3.Update(dal); no 3
>
>
> if I do it in the regular order like
> this.oleDbDataAdapter1.Update(dal);
> this.oleDbDataAdapter2.Update(dal);
> this.oleDbDataAdapter3.Update(dal); no 3
> this.oleDbDataAdapter4.Update(dal); no 4
>
> then I get this DbConcurrencyException. I do not understand why it is like
> that??? Do you have an explanation for that?
>
> Best regards,
> Patrick
>
>
> "Miha Markic [MVP C#]" schrieb:
>
>> Hi Patrick,
>>
>> Use only DataRow.Delete as Remove removes the row and adapter won't see
>> it.
>> Delete just marks row's state to Deleted (if the previouse state is Added
>> then row is removed from collection as there is no need to delete it).
>>
>> --
>> Miha Markic [MVP C#] - RightHand .NET consulting & development
>> SLODUG - Slovene Developer Users Group
>> www.rthand.com
>>
>> "Patrick" <Patrick@discussions.microsoft.com> wrote in message
>> news:42C475CD-FCE8-47C7-B623-3EA8FFC620C8@microsoft.com...
>> > Dear Ng,
>> >
>> > I have a 1(master table) : n(first child table) : m(second child table)
>> > relationship in my sql server and strongly typed dataset. Now I locate
>> > the
>> > corresponding row in the master table.
>> >
>> > DataAccessControl.DocumentTemplateRow rowTemplate =
>> > tblTemplate.FindBydocumentTemplateId(templateId);
>> >
>> > Then i request all child rows:
>> >
>> > DataRow[] rowsToDelete =
>> > rowTemplate.GetChildRows("DocumentTemplateDocumentField");
>> >
>> > Then I want to delete all child rows in the child tables:
>> >
>> > foreach (DataAccessControl.DocumentFieldRow row in rowsToDelete)
>> > {
>> > tblFields.RemoveDocumentFieldRow(row);
>> > }
>> > dac.updateDataAccessLayer();
>> >
>> > The delete rules of both relations (from the master to the first child
>> > and
>> > from the first to the second child) is set to cascade (in the database
>> > and
>> > in
>> > the dataset). But if I execute the code, just the rows in the second
>> > child
>> > table are deleted. What do I do wrong? If I use additionally the
>> > row.delete()
>> > command
>> >
>> > foreach (DataAccessControl.DocumentFieldRow row in rowsToDelete)
>> > {
>> > row.Delete();
>> > if (row.RowState == DataRowState.Deleted)
>> > tblFields.RemoveDocumentFieldRow(row);
>> > }
>> > dac.updateDataAccessLayer();
>> >
>> > I'll get a DBConcurrencyException! What is wrong? What I want to
>> > achieve
>> > is
>> > that the master record is kept and all child records are deleted.
>> >
>> > Thanks in advance and best regards,
>> > Patrick Braunschweig
>>
>>
>>