Typed datasets: Filling related datatables in C#

Please follow the link for more details:
http://www.java2s.com/Code/CSharp/Database-ADO.net/PopulateaDataSetwithmultipleDataTableobjectsusingmultipleSELECTstatements.htm
http://www.easysoft.com/developer/languages/csharp/ado-net-odbc.html
http://www.scribd.com/doc/53138145/An-Introduction-to-ADO-Net

can you UNION all the selects into a single statement?

select col1,col2 from tab1
union all
select col1,col2 from tab2
union all
select col1,col2 from tab3
union all
select col1,col2 from tab4


If not, can you provide a little more detail about the requirements?

Thanks IJZ and slightwv, I'm going to try and apply both of these suggestions and see what the results are.

I don't know of any way that you can run one sql statement, but have that data end up in different datatables on the Fill().  If this is possible, I would like to see it done.  

I don't use my relationships for binding, but I would assume you can...

As for the way to access the values of the current record, I assume you want to know how to access the child records when you are at the parent record?

What I do is pass the DataRow that I am currently at to a function to read specific items from the child records.  So if I had
For each row as DataRow in MyParentTable.Rows

Next
I would pass the row object to a method to look at the associated child records.  The code for that method would look something like what I have listed below...

The MyRelationName is NOTthe name of the object as in Dim MyRelationName as DataRelation.  It IS the name used when you are supplying the parent and child column info for the relation...
VB.Net
Dim Relation1 As New DataRelation("MyRelationName", _
            ds.Tables(0).Columns("Item1"), ds.Tables(1).Columns("Item1"), False)
C#
DataRelation Relation1 = new DataRelation("MyRelationName", ds.Tables(0).Columns("Item1"), ds.Tables(1).Columns("Item1"), false);

Not much of a C# programmer so I hope the conversion worked.  Also, this is code a wrote few years ago that I should probably go back and check out now that I know a little more. ;)

--------VB.Net
Private Sub DoSomething(ByVal dr As DataRow)
Dim tempDR As DataRow

If dr.GetChildRows("MyRelationName").Length > 0 Then
  tempDR = CType(dr.GetChildRows("MyRelationName").GetValue(0), DataRow)
  'Now tempDR has all the related records from the child table
  'you might have to loop through these to get what you want depending on your data.
End If

tempDr=Nothing
End Sub

----------C#
private void DoSomething(DataRow dr)
{
	DataRow tempDR = null;

	if (dr.GetChildRows("MyRelationName").Length > 0) {
		tempDR = (DataRow)dr.GetChildRows("MyRelationName").GetValue(0);
		//Now tempDR has all the related records from the child table
		//you might have to loop through these to get what you want depending on your data.
	}

	tempDR = null;
}

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Thanks for all comments and contributions.