Click Table Headings to Sort..

        <% if params[:v_order] == 'down' %>
        <%= link_to "e_date", :action =>"list_by_edate", :v_order =>
"up" %>
        <% else %>
        <%= link_to "e_date", :action =>"list_by_edate", :v_order =>
"down" %>
        <% end %>

i think you'll definitely not want to have three partials to display one
and the same stuff only in different order. i would do it by handing in
another parameter with the column name clicked.

first make your "if then" a oneliner:

<%= link_to "e_date", :action =>"list_by_edate", :v_order =>
params[:v_order] == 'down' ? "up" : "down" %>

then add a fieldname:

<%= link_to "e_date", :action =>"list_by_edate", :v_order =>
params[:v_order] == 'down' ? "up" : "down", :v_col => "edate" %>