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

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