Hi, under Trusty I was able to specify multiple PostgreSQL versions, but under Xenial only the last in the list of versions is installed. So in the example below, only PostgreSQL version 10 is installed.
Is there documentation somewhere of exactly which versions of Postgres are available via a simple addon and which require additional apt: config? I tired addons: {postgresql: "10"} and got:
[0K$ travis_setup_postgresql 10
e[33;1mStarting PostgreSQL v10e[0K
* Stopping PostgreSQL 9.2 database server e[80G
e[74G[ OK ]
* Stopping PostgreSQL 9.3 database server e[80G
e[74G[ OK ]
* Stopping PostgreSQL 9.4 database server e[80G
e[74G[ OK ]
* Stopping PostgreSQL 9.5 database server e[80G
e[74G[ OK ]
* Stopping PostgreSQL 9.6 database server e[80G
e[74G[ OK ]
PostgreSQL 10 is not installed!
sudo service postgresql start 10