Upgrade PostgreSQL in staging environment

[rbreslow]

After https://github.com/project-icp/bee-pollinator-app/issues/527 is complete, upgrade PostgreSQL for RDS in staging to match the version selected.

[hectcastro]

• [x] Install PostgreSQL 9.4 client libraries on the bastion

$ wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
$ sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ $(lsb_release -cs)-pgdg main" > /etc/apt/sources.list.d/pgdg.list'
$ sudo apt-get update
$ sudo apt-get install postgresql-client-9.4
$ sudo apt-get purge postgresql-client-9.3
$ sudo apt-get autoremove

• [x] Create a tmux session and establish a connection to the database

$ tmux new -s psql
$ psql -h database.service.icp.internal -U icp_bees -d icp_bees

• [x] Ensure all of the database tables have been vacuumed

icp_bees=> set maintenance_work_mem='256 MB';
icp_bees=> \timing
icp_bees=> VACUUM (FREEZE, ANALYZE, VERBOSE);

• [x] Upgrade from PostgreSQL 9.4.20 to 9.5.19
• [x] Before upgrading from PostgreSQL 9.5.x to 9.6.x, upgrade PostGIS

icp_bees=> ALTER EXTENSION postgis UPDATE;
icp_bees=> SELECT PostGIS_full_version();

• [x] Ensure all of the database tables have been vacuumed

icp_bees=> set maintenance_work_mem='256 MB';
icp_bees=> \timing
icp_bees=> VACUUM (FREEZE, ANALYZE, VERBOSE);

• [x] Upgrade from PostgreSQL 9.5.19 to 9.6.15
• [x] Upgrade PostGIS

icp_bees=> ALTER EXTENSION postgis UPDATE TO '2.3.7';
icp_bees=> SELECT PostGIS_full_version();

• [x] Install PostgreSQL 9.6 client libraries on the bastion

$ sudo apt-get install postgresql-client-9.6
$ sudo apt-get purge postgresql-client-9.4
$ sudo apt-get autoremove

• [x] Ensure all of the database tables have been vacuumed

icp_bees=> set maintenance_work_mem='256 MB';
icp_bees=> \timing
icp_bees=> VACUUM (FREEZE, ANALYZE, VERBOSE);

• [x] Ensure the appropriate postgres9.6 parameter group is associated with the RDS instance