public static DataTable Pivot(IDataReader dataValues, string keyColumn, string pivotNameColumn, string pivotValueColumn)
{
    DataTable tmp = new DataTable();
    DataRow r;
    int i, pValIndex, pNameIndex;
    string s;

    // Add non-pivot columns to the data table: 
    pValIndex = dataValues.GetOrdinal(pivotValueColumn);
    pNameIndex = dataValues.GetOrdinal(pivotNameColumn);

    // Loop through columns 
    for (i = 0; i <= dataValues.FieldCount - 1; i++)
    {
        if (i != pValIndex && i != pNameIndex)
        {
            DataColumn dc = new DataColumn(dataValues.GetName(i), dataValues.GetFieldType(i));
            tmp.Columns.Add(dc);

            // Add key column 
            if (dc.ColumnName == keyColumn)
                tmp.PrimaryKey = new DataColumn[] { dc };
        }
    }

    // now, fill up the table with the data 
    while (dataValues.Read())
    {
        // assign the pivot values to the proper column; add new columns if needed: 
        s = dataValues[pNameIndex].ToString();
        if (!tmp.Columns.Contains(s))
            tmp.Columns.Add(s, dataValues.GetFieldType(pValIndex));

        // Create new row after adding any additional columns 
        r = tmp.NewRow();

        // Add pivot value 
        r[s] = dataValues[pValIndex];

        // Add all non-pivot column values to the new row: 
        for (i = 0; i <= dataValues.FieldCount - 3; i++)
            r[i] = dataValues[tmp.Columns[i].ColumnName];

        // Look for key 
        DataRow rowFound = tmp.Rows.Find(r[keyColumn]);

        // Add new record if not found 
        if (null == rowFound)
        {
            tmp.Rows.Add(r);
        }
        else // Key already exists .. just update it 
        {
            rowFound[s] = dataValues[pValIndex];
        }
    }
    // Close the DataReader 
    dataValues.Close();
    // and that's it! 
    return tmp;
}