Creating a Database Dump
$> pg_dump -U postgres -d db_name -W --verbose > dumb_file_name.sql
For example, if we want to create a database dump for database app_dev and save it in a app_dev_aug2017.sql file, we can do:
$> pg_dump -U postgres -d app_dev -W --verbose >app_dev_aug2017.sql
Restoring Database Dump (from pg_dump)
$> psql -U postgres db_name < /path/to/database/dump/file.sql
* Feel free to replace postgres with your database username