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PostgreSQL error: Fatal: role "username" does not exist

I'm setting up my PostgreSQL 9.1. I can't do anything with PostgreSQL: can't createdb, can't createuser; all operations return the error message

Fatal: role h9uest does not exist

h9uest is my account name, and I sudo apt-get install PostgreSQL 9.1 under this account.
Similar error persists for the root account.

Afterwards you might run into FATAL: role "user" is not permitted to log in, check dba.stackexchange.com/questions/57723/… for that.
I answered this question here. Read this tutorial too "How to Install Postgres for Ubuntu Linux".
@Ruzenhack that tutorial link was exactly what I needed! Very clear and simple
psql -h localhost -U postgres
If you get the error role doesn't exist AND the error can't create role, it already exists check out this answer: stackoverflow.com/a/56658832/1689770

E
Erwin Brandstetter

Use the operating system user postgres to create your database - as long as you haven't set up a database role with the necessary privileges that corresponds to your operating system user of the same name (h9uest in your case):

sudo -u postgres -i

As recommended here or here.

Then try again. Type exit when done with operating as system user postgres.

Or execute the single command createuser as postgres with sudo, like demonstrated by drees in another answer.

The point is to use the operating system user matching the database role of the same name to be granted access via ident authentication. postgres is the default operating system user to have initialized the database cluster. The manual:

In order to bootstrap the database system, a freshly initialized system always contains one predefined role. This role is always a “superuser”, and by default (unless altered when running initdb) it will have the same name as the operating system user that initialized the database cluster. Customarily, this role will be named postgres. In order to create more roles you first have to connect as this initial role.

I have heard of odd setups with non-standard user names or where the operating system user does not exist. You'd need to adapt your strategy there.

Read about database roles and client authentication in the manual.


It is impossible to run sudo etc as user postgres... How to install a program? See this S2geometry installation problem.
Depending on the configuration, one might simply need su postgres.
sudo -u postgres doesn't work, while sudo -u postgres -i works! What does the -i flag do?
@parsecer: An interactive shell is started, similar to su, but based on sudo privileges. See man sudo.
WIth Postgres 12, I had to change -u to -U and I get "invalid option -- 'i'".
V
Vaibhav Mule

After trying many other people's solutions, and without success, this answer finally helped me.

https://stackoverflow.com/a/16974197/2433309

In short, running

sudo -u postgres createuser owning_user

creates a role with name owning_user (in this case, h9uest). After that you can run rake db:create from the terminal under whatever account name you set up without having to enter into the Postgres environment.


If you get an "insufficient privileges" error after this, you could append the -s flag to the above command. This will create your new user as a superuser. Please be aware of the security implications of this should you decide to do it.
I'm getting "insufficient privileges", but now I get ERROR: roll "username" already exists.
@ConnorLeech You can replace 'postgres' with the name of your PG super user. In my case it was my name.
I also had to use -s, and did not need to use sudo -u postgres (just createuser new_user worked fine)
psql: FATAL: role "jonny" does not exist okay so sudo -u postgres -s createuser jonny then why createuser: creation of new role failed: ERROR: role "jonny" already exists
t
the
sudo su - postgres

psql template1

creating role on pgsql with privilege as "superuser"

CREATE ROLE username superuser;
eg. CREATE ROLE demo superuser;

Then create user

CREATE USER username; 
eg. CREATE USER demo;

Assign privilege to user

GRANT ROOT TO username;

And then enable login that user, so you can run e.g.: psql template1, from normal $ terminal:

ALTER ROLE username WITH LOGIN;

I just did a new install of PostgreSQL 9.4.4 and was able to use the follow to create a new superuser: CREATE ROLE username superuser createdb login; which combines all three steps...
# GRANT ROOT to me; ERROR: role "root" does not exist
simpler version: sudo -u postgres createuser --superuser $USER; sudo -u postgres createdb $USER
@shacker #GRANT postgres TO username
I am using root to start the server then ```psql -U postgres -h 127.0.0.1 --command "CREATE USER postgresondocker WITH SUPERUSER PASSWORD 'postgresondocker';" &&\ createdb -O postgresondocker postgresondocker`` can I use root to do this if I add it to the pg_ident?
s
ssbl

This works for me:

psql -h localhost -U postgres

please add the password for above user.
@Vincent if the password was never changed after PostgreSQL installation, by default it is postgres (tested on Linux and Windows).
role postgres does not exist
To access a specific database you'll need to specify the db name psql -h hostname -U username -d database_name
M
Miles Erickson

Installing postgres using apt-get does not create a user role or a database.

To create a superuser role and a database for your personal user account:

sudo -u postgres createuser -s $(whoami); createdb $(whoami)


I needed to run the second part as: sudo -u postgres createdb $(whoami)
@SanD If you’ve created your own user account as a super user (via the -s flag in the first command), you can create the database as yourself. You won’t need to run createdb as postgres.
Great answer! Saved me hours of debugging!!
A
Abel
psql postgres

postgres=# CREATE ROLE username superuser;
postgres=# ALTER ROLE username WITH LOGIN;

psql postgres results: psql: FATAL: role "root" does not exist
psql postgres -U postgres? Depends on the user (-U) you have.
thank you! I struggled how to backup postgresql with root since I dont know postgres password
I get an error "must be a superuser to create a superuser"
K
Kalyan Halder

For version Postgres 9.5 use following comand:

psql -h localhost -U postgres

Hope this will help.


M
Mohideen bin Mohammed

Working method,

vi /etc/postgresql/9.3/main/pg_hba.conf local all postgres peer here change peer to trust restart, sudo service postgresql restart now try, psql -U postgres


It should be obvious that the trust method is only advisable in a completely secure environment. While access from untrusted connections is possible, never expose your DB cluster like that.
Check: If the postgresql service is not started, possibly there can be some error in the file pg_hba.conf
A
Andriy Tolstoy

For Windows users : psql -U postgres

You should see then the command-line interface to PostgreSQL: postgres=#


Thanks man. This worked for me on windows.
E
Erwin Brandstetter

In local user prompt, not root user prompt, type

sudo -u postgres createuser <local username>

Then enter password for local user.

Then enter the previous command that generated "role 'username' does not exist."

Above steps solved the problem for me. If not, please send terminal messages for above steps.


H
Henry

I installed it on macOS and had to:

cd /Applications/Postgres.app/Contents/Versions/9.5/bin
createuser -U postgres -s YOURUSERNAME
createdb YOURUSERNAME

Here's the source: https://github.com/PostgresApp/PostgresApp/issues/313#issuecomment-192461641


J
Jan

I did a healthcheck with docker-compose.

healthcheck:
  test: ['CMD-SHELL', 'pg_isready']
  interval: 5s
  timeout: 5s
  retries: 5

If you also have that change the user:

healthcheck:
  test: ['CMD-SHELL', 'pg_isready -U postgres'] # <<<---
  interval: 5s
  timeout: 5s
  retries: 5

C
Community

Manually creating a DB cluster solved it in my case.

For some reason, when I installed postgres, the "initial DB" wasn't created. Executing initdb did the trick for me.

This solution is provided in the PostgreSQL Wiki - First steps:

initdb Typically installing postgres to your OS creates an "initial DB" and starts the postgres server daemon running. If not then you'll need to run initdb


s
srghma

dump and restore with --no-owner --no-privileges flags

e.g.

dump - pg_dump --no-owner --no-privileges --format=c --dbname=postgres://userpass:username@postgres:5432/schemaname > /tmp/full.dump

restore - pg_restore --no-owner --no-privileges --format=c --dbname=postgres://userpass:username@postgres:5432/schemaname /tmp/full.dump


S
Siwei

for those who using docker and correctly followed the instructions from official doc, if you still met this problem, RESTART windows and try again.


a
ankit suthar

Follow These Steps and it Will Work For You :

run msfconsole type db_console some information will be shown to you chose the information who tell you to make: db_connect user:pass@host:port.../database sorry I don't remember it but it's like this one then replace the user and the password and the host and the database with the information included in the database.yml in the emplacement: /usr/share/metasploit-framework/config you will see. rebuilding the model cache in the background. Type apt-get update && apt-get upgrade after the update restart the terminal and lunch msfconsole and it works you can check that by typing in msfconsole: msf>db_status you will see that it's connected.


O
Oteri Eyenike

Follow these steps to get postgres working.

In your terminal, locate the Application Support folder with the following command. /Users/[name of the user]/library/application support Delete the application, Postgres. Reinstall the app and it should work just fine.


G
Guka Nozadze

Something as simple as changing port from 5432 to 5433 worked for me.


Has nothing to do w/ this issue, directly.