The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/10/static/tutorial-createdb.html
Description:
I ran "createdb mydb" but putting in my password I got "createdb: could not
connect to database template1: FATAL: password authentication failed for
user '(LOCAL USER)' "
Running "createdb -U postgres mydb" works with my password. Installation
seems to have created the user postgres without warning, but cmd and psql
both assume local user as default.