Update deleted Yast!!!

Today I had a red triangle in the updatemanager saying that there were

Very foolishly I typed the root password when asked to install the updates
and then it started deleting several yast modules one after another.
I also lost kde kicker, the menu button (and perhaps something else that I
have not noticed yet).
I tried to use the dvd to recover this, but it would not notice that yast
was missing. And of course yast and yast2 would not launch.

Fortunately I also had smart installed and was able to re-install yast.
I guess that if I did not have smart it would have meant a reinstall.

I learned:

  1. not to do updated blindly without knowing what is going to be
  2. to have another package manager installed.

Has anybody else had a similar experience?