HowTo setup Postgres on macOS

pgsql.sh

# 0. install a Postgres

  # we use HomeBrew for this
  brew install postgres
  # init file structure for all databases
  initdb /usr/local/var/postgres

# 1. create new user for a database

  # 1.1. user without password
  createuser username
  # 1.2. user with password
  createuser --pwprompt username

# 2. create new database

  # specify user that will access this database (created above)
  createdb -O username dbname

# 3. test connection

  # 3.1. user without password
  psql -U username dbname
  # 3.2. user with password
  psql -U username -W dbname