Recently, I need to upgrade my production PostgreSQL version from 11 to 12. I originally thought it would be simple by adjust docker-tag to newer version.

Unfortunately, when the container show up and has error as below

1. Make back up by pg_dumpall

docker exec {container_id} pg_dumpall -U {username} > dump.sql

2. Make new PostgreSQL container has your desire version with empty volumne
3. Copy backup file to container volumne and import it

docker exec {container_id} bash psql -U {username} -d {default-database} < dump.sql

Finally, grab a cup of coffee