Question

I tried the following and it failed

bash-3.2$ pg_ctl restart
pg_ctl: no database directory specified and environment variable PGDATA unset

I am using Macbook Pro and dont remember the directory where my data is stored and so can’t set PGDATA either, is there a way to restart Postgres at all without losing data?

Thank you

Answer 1

As you want to re-start Postgres I assume the server is already running.

Using the superuser account you can query the location of the data directory through SQL:

select name, setting
from pg_settings
where name = 'data_directory'

With that information you can supply the data directory to the pg_ctl command using the -D switch (see the manual for details)