Phil,

You can do something like this -

namespace ConsoleApplication1
{
   class Program
   {
       static void Main(string[] args)
       {
           DataTable dt = GetDataTable();
           dt.LoadDataRow(new Object[] { 0, "One", "Two" },
LoadOption.Upsert);
           dt.LoadDataRow(new Object[] { (int)dt.Compute("MAX (PK) + 1",
""), "One", "Two" }, true);
           dt.LoadDataRow(new Object[] { (int)dt.Compute("MAX (PK) + 1",
""), "One", "Two" }, true);
           dt.LoadDataRow(new Object[] { (int)dt.Compute("MAX (PK) + 1",
""), "One", "Two" }, true);
       }

       static DataTable GetDataTable()
       {
           DataTable dt = new DataTable();
           DataColumn dc = new DataColumn("PK");
           dc.AutoIncrement = true;
           dc.Unique = true;
           dt.Columns.Add(dc);

           dt.Columns.Add(new DataColumn("X"));
           dt.Columns.Add(new DataColumn("Y"));

           return dt;
       }
   }
}

Do note however that this will run hella slow - considering it is computing
the max everytime.
Enjoy !!

- Sahil Malik [MVP]
http://codebetter.com/blogs/sahil.malik/

Are you sure that you have the field defined correctly.  I would
suggest calling

da.fillschema(ds, SchemaType.Mapped, TableName)

before filling the ds from the data adapter.

This way the field will behave as an autoincrement.

Also, you need to declare your da withevents if there is a liklihood
that there are other people adding records at the same time.

Since the database is set up with an autoincrement, and the ds is
now setup with an autoincrement, the situation might arise where
two records are added from two differenet sources.  Each separate
ds will increment by one, but the database iteself will be out of
sync.  This is a problem with related records.

Handle the onUpdated event of the da and read back the
newly created autoincrement field and write it to the DS.

Good luck.

Jason.

Phil,

    You want to omit the auto-increment column from the list of values
you're supplying when adding the new row.  In VB.NET, use the Nothing
keyword.  C# developers would use null.  Your code will look something like:

 Dim tbl As New DataTable
 With tbl.Columns.Add("ID", GetType(Integer))
   .AutoIncrement = True
   .AutoIncrementSeed = -1
   .AutoIncrementStep = -1
 End With
 tbl.Columns.Add("OtherColumn", GetType(String))

 tbl.Rows.Add(New Object() {Nothing, "First row"})
 tbl.Rows.Add(New Object() {Nothing, "Second row"})

 Console.WriteLine(tbl.Rows(0)("ID"))
 Console.WriteLine(tbl.Rows(1)("ID"))

    I hope this information proves helpful.

David Sceppa
Microsoft
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