Change default app via console

[Grant]

> I do not use gnome and evince but i think you can check desktop files
> in /usr/share/applications and find file(s) with 'Exec=evince-previewer
> %U' And change it to 'Exec=evince %U'
>
>> I'd like to have PDF documents opened with the full evince app instead
>> of evince's "GNOME Document Previewer" since I can't get copy/paste to
>> work from the previewer.  How can I make that change via console?


Ideally I would be able to edit the app/filetype associations in the
userdir.  Which files there control that?

- Grant