Postgres is a particular implementation of an SQL-based relational database.
It is available on the free tier of Heroku, which is why we tend to use it for our database applications in this course.
This article isn’t (yet) a complete introduction to Postgres; instead it’s a collection of tips and notes that we’ve found useful in dealing with Postgres databases on Heroku, and with Spring Boot Java webapps.
On the free tier of Heroku, you are permitted only up to 10,000 rows total across all tables in your database.
You can monitor how close you are getting with:
heroku pg:info --app APP
You can dump the contents of a postgres database on Heroku to a special binary format used by the
This is documented here: https://devcenter.heroku.com/articles/heroku-postgres-import-export, but
- NOTE that you may need the
--app APPsuffix on the commands such as
The file that is downloaded is called
latest.dump, and it’s in an ideosyncratic binary format.
That can be converted to a text
.sql file with the process documented here: https://stackoverflow.com/questions/21429335/how-do-i-convert-a-binary-pgdump-compressed-to-a-plain-sql-file
pg_restore -f latest.sql latest.dump
That requires you to have postgres installed on your local machine so that you have the
pg_restore command available.