how to create username and password in postgresql code example

Example 1: create db user postgres

sudo -u postgres psql
postgres=# create database mydb;
postgres=# create user myuser with encrypted password 'mypass';
postgres=# grant all privileges on database mydb to myuser;

Example 2: How do I add a user to a postgres database? cli

psql=# grant all privileges on database  to 

Example 3: create user and password postgres

dropuser username