PG Error could not connect to server: Connection refused Is the server running on port 5432?

Question

I recently updated my machine (MacBook Pro running Mountain Lion) and ever since then, whenever I set up a rails project, my machine craps out and cannot connect to PG. Curr

Answer 1

Run in your command line

postgres -D /usr/local/var/postgres

If the result is like the next one

LOG:  skipping missing configuration file "/usr/local/var/postgres/postgresql.auto.conf"
FATAL:  database files are incompatible with server
DETAIL:  The data directory was initialized by PostgreSQL version 10, which is not compatible with this version 11.

Run

brew postgresql-upgrade-database

Based in this post

Answer 2

This is quite easy than your think because If you update your mac then process is running but postmaster.pid file is missing from /usr/local/var/postgres/ here. so you need to start process for postgres which create postmaster.pid.

If progress is running then -

Stop manually:

pg_ctl -D /usr/local/var/postgres stop -s -m fast

Start manually:

pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log start

now all are working...