Please, I need help with my postgres server. I have problems starting the server. I was using the app here a few months ago and everything was fine. Today I spent hours trying to start it yet couldn't. I then realised I had another instance of PostgreSQL installed. I uninstalled version 9.6 blocking my app.
Now after trying again, the PostgreSQL app throws the error when I use psql:
FATAL: role "username" does not exist
I didn't set the role or user but it somehow took my username and is throwing does not exist. Please, how do I start my server. I have seen someone with a similar issue here but unlike in his case, I didn't even get to start the server. not to speak of deleting the database. Please, how do I address this? Any help would be appreciated.
I also noticed he was able to execute
which psql
which returned his supposed psql path. It does not return anything in my case. Not sure how the configuration works, this is my second time using this database and it failed right away.
Thank you for your time, as answered in one of the SO question here. Running
sudo -u postgres -i
did give me access to postgres, but if you are using the postgres app like myself here . Running psql commands would not work for you as postgres is not installed globally on your machine. But running
'/Applications/Postgres.app/Contents/Versions/9.5/bin'/psql -p5432
which is the exact command the postgres app execute when you attempt to start the service works great and start the service for me. You can then proceed and add the role and database your postgres app looks for by default. So in summary. Below is what worked for me.
$sudo -u postgres -i
$'/Applications/Postgres.app/Contents/Versions/9.*/bin'/psql -p5432
#CREATE USER postgres SUPERUSER;
#CREATE DATABASE postgres WITH OWNER postgres;
I am trying to create a database using PostgreSQL 9.4. I type "psql" in the command prompt, and then it asks for a password. I provide the password I set during the installation, but it says the authentication failed. After checking online, I concluded that I need to be using the superuser, named "postgres", which is the system user whose password is the one I set during the installation.
I am now trying to set PostgreSQL to this superuser. I spent a lot of time surfing the internet for a solution but wasn't able to solve the problem. I tried postgres ALTER USER myuser WITH SUPERUSER (I wrote that in the Windows command prompt), but it said that "alter" isn't recognized. Now, when I try to use PostgreSQL, my main problem is that I get the error: "role MYUSERNAME does not exist". (this is after I edited pg_hba.conf to make it not ask for a password)
By default, psql uses the name of the operating system to log in, to a database of the same name. If you want to log in as user postgres you should do:
psql -u postgres <any other options>
If a password is asked for, you give the password of the postgres user. You are now connected to the postgres database, where you really shouldn't be doing anything, except create new users (which are global to the installation) and other databases.
Once in the console, you can create new users like:
CREATE ROLE myusername LOGIN PASSWORD secret;
And new databases like:
CREATE DATABASE myowndb;
ALTER DATABASE myowndb OWNER TO myusername;
Then you log out from the console with \q.
In order to be able to access PostgreSQL using the new database, you have to edit the pg_hba.conf file (sample, modify to match your network settings):
host myowndb myusername 192.168.0.0/16 md5
Now you restart the PostgreSQL server from the Services tab in Administrative tools on the Control Panel.
Then you can log in to your new database:
psql -u myusername -d myowndb
Or use other clients like pgAdminIII.
Under Windows. The Postgres bin directory ships with the user commands createuser.exe and dropuser.exe.
Say, if running initdb (effective fresh install) or for some other reason there is no superuser (like the question).
Can also manage the users and superusers (-s option) with the above two commands. ie.
Create the superuser called postgres:
C:"Program Files"\PostgreSQL\15\bin\createuser.exe -s postgres
Drop a user:
C:"Program Files"\PostgreSQL\15\bin\dropuser.exe postgres
Working on OS X 10.10, installed postgreSQL and PostGIS from
here, psql vers 9.3.5. I am having a hard time getting postgreSQL running.
I installed the packages as admin on my computer. My username is christoph
The only way I can log in is via:
$ psql -U postgres
I want to create user called christoph, as my admin name on the computer.
I tried (from the terminal, without being "logged in into psql"):
$ sudo -u postgres createuser christoph
> sudo: unknown user: postgres
Then I read a little and tried (from the terminal, without being "logged in into psql"):
$ sudo -u _postgres createuser christoph
> Password: ****
> Could not connect to database postgres: FATAL: role "_postgres" does not exist
Why isn that working?
On recent version of OS X and with some installation methods the system user is created with a '_' prepended or appended to 'postgres', so the name of your system user is postgres_ or _postgres in your case, not 'postgres'. I don't use OS X, so I don't know what drives them to do this. Seems like they want to adhere to a naming schema for system accounts.
Not to be confused with the Postgres DB user (login role) of the name postgres. This mismatch causes all sorts of confusion. At least people become aware of the different meaning of some syntax elements ...
That's why you can log into Postgres via:
$ psql -U postgres
postgres is the DB role here, not the OS user.
But this won't work:
$ sudo -u postgres
Because there is no OS user of that name. Try instead:
$ sudo -u _postgres
But then peer authentication still won't work, because there is no DB user of the same name _postgres. Related answer:
Postgres user does not exist?
The authentication method activated by default in standard installations is peer authentication, where a system user on the local system has password-less access to a database role of the same name. That explains the last error message:
Could not connect to database postgres: FATAL: role "_postgres" does not exist
Your system tried to log into the DB with the same name as your current OS user using peer authentication, which fails due to the naming mismatch.
Your last command should work like this:
$ sudo -u _postgres createuser -U postgres christoph
The added -U postgres is an option to createuser specifying the DB role to log in with.
You still have to enter the password. I would consider using an entry in the a .pgpass file for password-less access, while the system user is different from the supposedly associated DB role.
Related:
Login Failed with Existing User on PostgreSQL
Run batch file with psql command without password
createdb foo gives an invalid password for user (my username)
I can't login with
sudo psql
How do I reset my postgres user accounts?
Is it something I can do in the hba_conf file?
EDIT:
I was beginning a Postgres tutorial and wanted to have a fresh install. I ran
brew update
brew uninstall postgresql
brew install postgresql
pg_ctl -D some/path
createdb
This could be two things: you lost/misset the password, or Postgres might be configured in a way that prevents you from logging in.
Resetting the password:
Most of the time Postgres runs as user "postgres". Try su - postgres as root, and then run psql. If that doesn't work, you'll need to figure out what user postgres is running as, and su to that user. From there you can reset the password for the user. Also, make sure that your user is allowed to log in -- the default is to disable login for a new role .
Changing the configuration:
Find the pg_hba.conf file and edit it to permit password login. This file is usually loacted in /var/lib somewhere. On my Scientific Linux server its at: /var/lib/pgsql/9.2/data/pg_hba.conf, but on my Gentoo server its at /etc/postgresql-9.3/pg_hba.conf -- so locate pg_hba.conf might help you find it. This file is usually fairly well commented, and there is a manual page for it here: http://www.postgresql.org/docs/devel/static/auth-pg-hba-conf.html.
I'm a postgres novice.
I installed the postgres.app for mac. I was playing around with the psql commands and I accidentally dropped the postgres database. I don't know what was in it.
I'm currently working on a tutorial: http://www.rosslaird.com/blog/building-a-project-with-mezzanine/
And I'm stuck at sudo -u postgres psql postgres
ERROR MESSAGE: psql: FATAL: role "postgres" does not exist
$ which psql
/Applications/Postgres.app/Contents/MacOS/bin/psql
This is what prints out of psql -l
List of databases
Name | Owner | Encoding | Collate | Ctype | Access privileges
------------+------------+----------+---------+-------+---------------------------
user | user | UTF8 | en_US | en_US |
template0 | user | UTF8 | en_US | en_US | =c/user +
| | | | | user =CTc/user
template1 | user | UTF8 | en_US | en_US | =c/user +
| | | | | user =CTc/user
(3 rows)
So what are the steps I should take? Delete an everything related to psql and reinstall everything?
Thanks for the help guys!
NOTE: If you installed postgres using homebrew, see the comment from #user3402754 below.
Note that the error message does NOT talk about a missing database, it talks about a missing role. Later in the login process it might also stumble over the missing database.
But the first step is to check the missing role: What is the output within psql of the command \du ? On my Ubuntu system the relevant line looks like this:
List of roles
Role name | Attributes | Member of
-----------+-----------------------------------+-----------
postgres | Superuser, Create role, Create DB | {}
If there is not at least one role with superuser, then you have a problem :-)
If there is one, you can use that to login. And looking at the output of your \l command: The permissions for user on the template0 and template1 databases are the same as on my Ubuntu system for the superuser postgres. So I think your setup simple uses user as the superuser. So you could try this command to login:
sudo -u user psql user
If user is really the DB superuser you can create another DB superuser and a private, empty database for him:
CREATE USER postgres SUPERUSER;
CREATE DATABASE postgres WITH OWNER postgres;
But since your postgres.app setup does not seem to do this, you also should not. Simple adapt the tutorial.
For MAC:
Install Homebrew
brew install postgres
initdb /usr/local/var/postgres
/usr/local/Cellar/postgresql/<version>/bin/createuser -s postgres or /usr/local/opt/postgres/bin/createuser -s postgres which will just use the latest version.
start postgres server manually: pg_ctl -D /usr/local/var/postgres start
To start server at startup
mkdir -p ~/Library/LaunchAgents
ln -sfv /usr/local/opt/postgresql/*.plist ~/Library/LaunchAgents
launchctl load ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist
Now, it is set up, login using psql -U postgres -h localhost or use PgAdmin for GUI.
By default user postgres will not have any login password.
Check this site for more articles like this: https://medium.com/#Nithanaroy/installing-postgres-on-mac-18f017c5d3f7
The key is "I installed the postgres.app for mac." This application sets up the local PostgreSQL installation with a database superuser whose role name is the same as your login (short) name.
When Postgres.app first starts up, it creates the $USER database,
which is the default database for psql when none is specified. The
default user is $USER, with no password.
Some scripts (e.g., a database backup created with pgdump on a Linux systsem) and tutorials will assume the superuser has the traditional role name of postgres.
You can make your local install look a bit more traditional and avoid these problems by doing a one time:
/Applications/Postgres.app/Contents/Versions/9.*/bin/createuser -s postgres
which will make those FATAL: role "postgres" does not exist go away.
createuser postgres --interactive
or make a superuser postgresl just with
createuser postgres -s
And if you are here in 2023 and wondering what works with the latest Postgres on the latest macOS (macOS Monterey )
follow this:
brew install postgresql
createuser -s postgres
brew services restart postgresql
This happens when you run initdb with a user whose ID is not postgres, without specifying the postgres username with --username=postgres or -U postgres.
The database cluster is then created with the system's user account that you used to run initdb, and it is given superuser permissions.
To fix it, simply create a new user named postgres with the option --superuser using the createuser utility that comes with Postgres. The utility can be found in the Postgres' bin directory. e.g.
createuser --superuser postgres
If you have a custom hostname or port then be sure to set the appropriate options.
Don't forget to delete the other user account that was created for you by initdb.
If you installed postgres from brew, run this in your terminal :
/usr/local/opt/postgres/bin/createuser -s postgres
First you need create a user:
sudo -u postgres createuser --superuser $USER
After you create a database:
sudo -u postgres createdb $USER
Change $USER to your system username.
You can see the the complete solution here.
I needed to unset $PGUSER:
$ unset PGUSER
$ createuser -s postgres
For me, this code worked:
/Applications/Postgres.app/Contents/Versions/9.4/bin/createuser -s postgres
it came from here:
http://talk.growstuff.org/t/fatal-role-postgres-does-not-exist/216/4
If you installed postgres from Brew and are using an Apple Silicon (M1) mac, run this in your terminal:
/opt/homebrew/opt/postgresql/bin/createuser -s postgres
If you're using an Intel (x86) mac, run this in your terminal:
/usr/local/opt/postgres/bin/createuser -s postgres
Running this on the command line should fix it
/Applications/Postgres.app/Contents/Versions/9.4/bin/createdb <Mac OSX Username Here>
This article helped me to solve same issue psql: FATAL: role “postgres” does not exist.
I am using mac, so I entered this command in terminal:
createuser -s postgres
And it worked for me.
This worked for me
createuser -s postgres
note: I'm using mac catalina
If you're using docker, make sure you're NOT using POSTGRES_USER=something_else, as this variable is used by the standard image to know the name of the PostgreSQL admin user (default as postgres).
In my case, I was using this variable with the intent to set another user to my specific database, but it ended up of course changing the main PostgreSQL user.
We have a db named postgres after brew install postgresql and brew services start postgresql. So we can open psql like this by default.
psql postgres
And then we can add users with any name like this in that psql console.
CREATE USER postgres
And if we want a super user, then we can add SUPERUSER at the end.
For m1 chips, if you have not installed postgresql package by homebrew, install it in terminal with:
brew install postgre
then create a username manually by:
/opt/homebrew/bin/createuser -s <username>
your error is probably fixed; but if you occur the error
FATAL: database "databasename" does not exist
then you have to create your database manually by:
/opt/homebrew/bin/createdb -U <username> <databasename>
Dropping the postgres database doesn't really matter. This database is initially empty and its purpose is simply for the postgres user to have a kind of "home" to connect to, should it need one.
Still you may recreate it with the SQL command CREATE DATABASE postgres;
Note that the tutorial mentioned in the question is not written with postgres.app in mind.
Contrary to PostgreSQL for Unix in general, postgres.app tries to look like a normal application as opposed to a service that would be run by a dedicated postgres user having different privileges than your normal user. postgres.app is run and managed by your own account.
So instead of this command: sudo -u postgres psql -U postgres, it would be more in the spirit of postgres.app to just issue: psql, which automatically connects to a database matching your users's name, and with a db account of the same name that happens to be superuser, so it can do anything permissions-wise.
This is the only one that fixed it for me :
createuser -s -U $USER
For what it is worth, i have ubuntu and many packages installed and it went in conflict with it.
For me the right answer was:
sudo -i -u postgres-xc
psql
I've faced similar problem today, actually i was not sure what was the username. Here is the 2 thing, if you are under enterprise and don't have system admin access the postgres will create your enterprise username as the postgres admin username. If you install through Homebrew it will definitely happening. In that case simply run your psql service with brew and do an echo of the username
brew services start postgresql
then
echo $USER
You will see your username of the postgres user.
If you are experiencing this problem right after running a docker container try destroying the container and recreating it. That solved it for me:
docker-compose down
docker-compose up --force-recreate
This should recreate the db with postgresuser as default user
With a new mac (M1) and latest postgres (14.0) installed via homebrew, nothing helped me from this topic, but i just reinstalled postgres and it helped:
brew services stop postgresql
rm -rf /opt/homebrew/var/postgres/*
brew reinstall postgresql
initdb --locale=C -E UTF-8 /opt/homebrew/var/postgres
brew services restart postgresql
So, it's a miracle or something like that...
Then just:
psql -d postgres
If you are a MAC (M1) user and installed the Postgres using HomeBrew then follow these steps:
Check your Postgres location using which psql
then run the command /opt/homebrew/bin/createuser -s postgres if the output for the first command is /opt/homebrew/bin/psql
The idea is to create a user named 'postgres' using the Postgres installation location. So you may need to change the command based on the location of your Postgres.
On Ubuntu system, I purged the PostgreSQL and re-installed it. All the databases are restored.
This solved the problem for me.
Advice - Take the backup of the databases to be on the safer side.
Context
I am adding an answer for a case I have not seen here, which is an edge case if you have multiple users on the same machine and the user who is trying to use postgres services is not the user who installed postgres on the machine.
What I have tried
Among other similar commands, for me all these commands failed:
createuser -s [your username]
# createuser: error: connection to server on socket "/tmp/.s.PGSQL.5432" failed: FATAL: role "[your username]" does not exist
createuser -s postgres
# createuser: error: connection to server on socket "/tmp/.s.PGSQL.5432" failed: FATAL: role "[your username]" does not exist
sudo -u postgres createuser --superuser [your username]
# sudo: unknown user: postgres
# sudo: error initializing audit plugin sudoers_audit
psql -U postgres
# psql: error: connection to server on socket "/tmp/.s.PGSQL.5432" failed: FATAL: role "postgres" does not exist
Reason
The reason is because neither postgres role nor [your username] (aka whoami on your command line) are in postgres.
Solution
In such edge case I had to first login with the user who installed postgres:
sudo su - [username that installed postgres]
And then create a role for my new user:
createuser -s [your username]
On Mac, executing
createuser -s postgres
in a terminal worked.
I don't think that sudo is needed here because psql -l returns a list of databases. This tells me that initdb was run under the user's current user, not under the postgres user.
You can just:
psql
And continue the tutorial.
I would suggest A.H's general points of creating the postgres user and db because many applications may expect this to exist.
A brief explanation:
PostgreSQL will not run with administrative access to the operating system. Instead it runs with an ordinary user, and in order to support peer authentication (asking the OS who is trying to connect) it creates a user and db with the user that runs the initialization process. In this case it was your normal user.
I became stuck on this issue having executed brew services stop postgresql the day prior. The day following: brew services start postgresql would not work. This is because as is shown when you install using homebrew. postgresql uses a launchd ... which loads when your computer is powered on. resolution:brew services start postgresql Restart your computer.
The \du command return:
Role name = postgres#implicit_files
And that command postgres=# \password postgres return error:
ERROR: role "postgres" does not exist.
But that postgres=# \password postgres#implicit_files run fine.
Also after sudo -u postgres createuser -s postgres the first variant also work.