title: vb.net Linq select from enumareable
body: <p>I have the following LINQ query which will group by a column and add each group to a datatable in a dataset:</p>
  
  <pre><code>Dim ds As New DataSet
  Dim query = From r In bookedorders Group By key = r.Field(Of Integer)("productgroup") Into Group
  For Each grp In query
      Dim x As New DataTable
      x = grp.Group.CopyToDataTable()
      ds.Tables.Add(x)
  Next
  </code></pre>
  
  <p>How can I select specific columns from table <code>bookedorders</code> in this query before adding them to the DataTable?
  I have 18 columns and I just want to show 4 in the resulted <code>DataTable</code>.</p>