Question: I have something like this sql query : `Select Sum(value) from Database.table`. And i post this in to some gridView in asp.net web form. 

```
<asp:gridview id="foo" runat="server" autogeneratecolumns="false">
    <columns>
        <asp:boundfield datafield="ID" headertext="Identifier" />
    </columns> 
</asp:gridview>

```

this `Sum(VALUE)` don't have `datafield` or i dont know what is this .How to change `HeaderText of SUM(value) column`

Answer: 
There is a `schema_migrations` table created w/I your postgres database, you can reset the migration status by dropping that table (`drop table schema_migrations;`).
I had a similar problem with **\* No File \***. I did a rake db:migrate:status and found that rake was looking for some old migrations that I had saved in another folder under the migrate folder. So, I deleted the old migrations and schema.rb. Then I did rake db:drop, rake db:create, and rake db:migrate. That solved the problem.