Linq groupby on IEnumerable DataRow
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I have a collection of DataRow objects. I should select distinct rows, based on the column 'URL_Link'. Following [this post][1], I came up with below code.  
Is it possible to apply it for DataRow collection?

    IEnumerable<DataRow> results = GetData();  
    results.GroupBy(row => row.Field<string>("URL_Link")).Select(grp => grp.First());

It is syntactically correct, but it does not solve the problem. It doesn't remove duplicate rows. What am I doing wrong?


  [1]: http://stackoverflow.com/questions/1300088/distinct-with-lambda