Large Hadron Migrator VS PgHero

No you didn't. They're doing what is often referred as "online schema change" using https://github.com/github/gh-ost (but the concept is the same than percona's pt-online-schema-change, or https://github.com/soundcloud/lhm.

Is there anything similar for MySQL? There is https://github.com/soundcloud/lhm but it's pretty much outdated nowadays

I may do it from the console or a task if I wanted to modify a large number of records, e.g. something in my Users table. I think you need a sense of how long the update will take - I'm not sure if there's any issue with migrations timing out or such like. If I modify my Users schema it takes 5 minutes or so as it has to make a copy of the table and swap it in and that works fine - https://github.com/soundcloud/lhm

For our production PGSQL databases, we use a combination of PGTuner[0] to help estimate RAM requirements and PGHero[1] to get a live view of the running DB. Furthermore, we use ZFS with the built-in compression to save disk space. Together, these three utilities help keep our DBs running very well.

[0] https://pgtune.leopard.in.ua

[1] https://github.com/ankane/pghero

I am using https://github.com/ankane/pghero/ and this is one of its features with GUI

I use either PgHero or Rails PG Extras on every project

There are tools available which can look at your Postgres logs and tell you if you need to add indexes, I've used https://github.com/ankane/pghero before and it seems decent.

https://github.com/ankane/pghero (open source equivalent to pganalyze)

- [pghero](https://github.com/ankane/pghero)

pghero