问题
i am on ubuntu 12.04 server and i am trying to install postgresql. As of now, i have successfully installed it but unable to configure it. I need to create a role to move ahead and i ran this command in terminal :
root@hostname: createuser -s -r postgres
and it said :
createuser: could not connect to database postgres: FATAL: role "root" does not exist
Fine, so i did :
su - postgres
and then tried again
postgres@hostname: createuser -s -r postgres
and i got the error
createuser: could not connect to database postgres: FATAL: role "postgres" does not exist
and i get the same error when i do
psql -d dbname
Its like a loop, i am unable to create a role postgres because a role postgres does not already exist.
How do i fix this ?
The postgres version seems to be 9.1.x and the ubuntu version is 12.10
回答1:
Turns out i had installed postgres-xc and postgresql on my machine. I had to knock off postgres-xc completely. And it was a little difficult to do that because, there was always an error --purge remove postgres-xc and the uninstallation could not continue.
There seems to be some kind of a packaging bug. (details on launchpad).
Eventually, i ended up doing this to make it work.
After that i uninstalled postgresql and installed it back to make it work.
回答2:
Read postgresql tutorial it doesn't matter if it's Ubuntu or other Linux.
EDIT before creating role or anything else on fresh install you need to create database cluster: have you created it?
initdb -D /usr/local/pgsql/data
You need to be logged as user postgres on linux machine. Here is more info.
来源：https://stackoverflow.com/questions/15591749/unable-to-create-user-postgres-role-postgres-does-not-exists