在ubuntu上安装PG数据库

Question

我试图在我的ubuntu系统上安装PG，但是我无法克服sudo apt-get install postgresql-9.1的这个错误：

Package postgresql-9.1 is not available, but is referred to by another package. 
This may mean that the package is missing, has been obsoleted, or is only available
from another source

或sudo apt-get install postgresql-9.4的此错误：

Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package postgresql-9.4
E: Couldn't find any package by regex 'postgresql-9.4'

或sudo apt-get install postgresql postgresql-contrib的此错误：

Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 postgresql : Depends: postgresql-9.3 but it is not going to be installed
 postgresql-contrib : Depends: postgresql-contrib-9.3 but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

有没有人知道这是为什么，或者我必须做些什么来纠正它？(我以前运行过sudo apt-get update )。

Answer 1

您的计算机上似乎安装了postgres-xc，这是用于多主群集的PostgreSQL旧版本的分叉。问题是Postgres-XC与PostgreSQL不兼容。

假设您需要PostgreSQL (而不是Postgres-XC)，我建议您完全卸载postgres-xc和postgres-xc-client，然后再尝试重新安装postgresql-*包。