Answers for "login as a user in postgres"

how to login using a particular user postrges

psql -d mydb -U myuser -W
psql -h myhost -d mydb -U myuser -W

Make a user in Postgresql

CREATE USER jonathan;
CREATE USER davide WITH PASSWORD 'jw8s0F4';
CREATE USER miriam WITH PASSWORD 'jw8s0F4' VALID UNTIL '2005-01-01';
CREATE USER manuel WITH PASSWORD 'jw8s0F4' CREATEDB;