How heroku postgres works with 0 bytes of RAM

Question

On heroku postgres plan page https://elements.heroku.com/addons/heroku-postgresql, it is mentioned that for hobby plans there is 0 bytes of RAM. Does it mean that Postgres is working without RAM?

Answer 1

The 0 bytes RAM refers to the amount of in-memory cache allocated to your datastore. Heroku says...

The lack of an in-memory cache limits performance, because the data can’t be accessed on low-latency storage.