Ruby on Rails migrations into a single migration?

Hi all.

So i am a ruby on rails developer and I haven't used this feature earlier. So asking exactly how do I squash ruby on rails migrations into a single one?

Any help would do.

Afaik, there's no automated way of doing this. And when I do—that is before I push to a shared repo—, I do it manually. 

Also, what's up with the link? Is this a new kind of smart spam bot?