How to reset password in postgresql (psql) for particular role in case when I list the role name it is not exist?

Question

I have installed PostgreSQL for a long time but just currently learning it.

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Here is what happened if I run psql in the command prompt

C:\Users\VandaRsq>psql 
Password for user Vanda Rashq:

Since I forgot the password for the Vanda Rashq role but I remember for the postgres role, I run psql -U postgres.

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I tried to list the role by using du command and the result is this:

I also tried using SELECT rolname FROM pg_roles command and yield:

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I have tried to follow this tutorial and do ALTER USER "Vanda Rashq" WITH PASSWORD 'new_password'; but it returns ERROR: role "Vanda Rashq" does not exist

My question is, does the "Vanda Rashq" role actually still exist? If yes, how to reset (change) the password in case I forgot the password? If not, how to change the default role when running psql to postgres role

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Notes: I have tried to uninstall the PostgreSQL and remove all of the directories but when I try to run psql, it still ask Password for user Vanda Rashq

Answer 1

If the user you're looking for is not listed after calling \du in psql then the user does not exist in the database.

Btw, you could also use a select to retrieve information about database users: select * from pg_catalog.pg_user;

EDIT:

Like @jjanes pointed out you get challenged for a password based on the USER configuration in yourpg_hba.conf (see docs).

For authentication method peer it is stated:

Obtain the client's operating system user name from the operating system and check if it matches the requested database user name.