PGUSER doesn't work with initdb and pg_ctl initdb. Lets explain, where this can be important. For instance in MacOS the
mostconvenient way to manage PostgresQL is homebrew.
To install PostgresQL:
brew install postgresql
To upgrade:
brew upgrade postgresql
this will upgrade soft and to upgrade DB
brew postgresql-upgrade-database
The later command do: install previous version of PostgresQL, move postgresql dir to postgesql.old, run pg_upgrade and
soon. Convenient.
But this command don't have option to define name of superuser. The only variant to set name off superuser is to use
PGUSERenvironment variable. But PGUSER understand only pg_upgrade, but not initdb.
