[Empact]

In the Rails world, the gem strong_migrations can be used to detect these: https://github.com/ankane/strong_migrations

The docs include a handy articulation of fixes.

[tnmom]

ankane is some kind of superhuman cyborg. Seems like about 25% of the really useful gems I use have that name in the URL...

[hamilyon2]

Pghero is kind of gem

[rkaveland]

This is super cool, I love how it suggests safer ways to achieve the same goal for many common risky migrations. Definitely going to sit down and study these.

[alflervag]

Nice, I wasn’t aware of this one.