I am a software engineer with 8 years of experience in enterprise content management for insurances. My interest in Postgres grew along those years because of interactions with many different databases and good experiences with Postgres. Because of this, Postgres is my database of choice for most of my ECM or Java projects. I almost exclusively use Postgres running as a docker container, and I maintain a custom set of Postgres docker images.
Upgrading big databases from one PG version to another can involve quite a bit of downtime when using pg_upgrade. In many situations, this downtime is not acceptable, or very expensive. Since Postgresql 10 a new replication method, called 'logical replication', is supported out of the box. In this presentation, a downtimeless upgrade of Postgresql 10 to Postgresql 11 will be demonstrated, using Docker, docker-compose and HAProxy.