Document procedure to upgrade PostgreSQL chart image to 11.x
Summary
Document the processes to upgrade the version of PostgreSQL used by the stable/postgresql
/ bitnami/postgresql
chart, if deployed. Specifically, how to move from the current PG 10.x of the 3.x releases of these charts to that of PG 11.x as will be the default in 4.x releases of these charts at the turn of %13.0
Details
As found in #1849 (closed), there is no method to automatically upgrade/downgrade the database files related to the stable/postgresql
chart's StatefulSet. As a result, a manual step is required to backup, reset, and restore the database in order to perform this upgrade.
We have done this previously, as seen in the upgrade instructions for 3.0.0 release. We can most likely reuse this script, and most of these steps.