starting postgres server on Mac - macos

Question

I am having this issue third or forth time where after restarting my Mac (Yosemite and same thing with previous OSX version) postgres server doesn't start. I had installed my postgres following this link. Any idea why this consistently occurs after every restart?
typing psql it gives
psql: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/tmp/.s.PGSQL.5432"?

Answer 1

I just fixed this on my mac. I used homebrew to install postgres. These are the steps I took to get up and running again.
First check the status of the postgresql service:
pg_ctl -D /usr/local/var/postgres status
if you see this pg_ctl: no server running, unload the launch agent:
launchctl unload ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
then move your existing postgres data (move rather than delete - cheap insurance):
mv /usr/local/var/postgres /usr/local/var/postgres-deletemewhenitsallgood
then initialize your postgres database:
initdb /usr/local/var/postgres -E utf8
then load your launch agent:
launchctl load ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
OR start it:
pg_ctl -D /usr/local/var/postgres -l /usr/local/var/postgres/server.log start
Now check the status again:
pg_ctl -D /usr/local/var/postgres status
if you see something like this, you are good to go.
pg_ctl: server is running (PID: 61295)
/usr/local/Cellar/postgresql/bin/postgres "-D" "/usr/local/var/postgres"
Then you can go into your postgres database:
psql -d postgres
Also after that you need to add postgress Role.
To Resolve missing postgres Role error

Answer 2

To start postgres server on mac:
install postgres with brew
brew install postgres
ensure you have permissions for /usr/local/postgres
sudo chown -R `whoami` /usr/local
then init the db:
initdb /usr/local/var/postgres
To have launchd start postgresql at login:
ln -sfv /usr/local/opt/postgresql/*.plist ~/Library/LaunchAgents
To load postgresql:
launchctl load ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
To check your version:
psql --version
And to access postgres
psql -d postgres