我需要重新安装postgresql，ubuntu14.04安装 9.5 版本后，postgreql我遇到了这个错误，另外我尝试过谷歌搜索一些解决方案，但我无法解决问题，而且我的postgresql-9.5-main.log是空的，那是一些奇怪的东西。
因此错误如下：
Ver Cluster Port Status Owner Data directory Log file
9.5 main 5432 down postgres /var/lib/postgresql/9.5/main /var/log/postgresql/postgresql-9.5-main.log
update-alternatives: using /usr/share/postgresql/9.5/man/man1/postmaster.1.gz to provide /usr/share/man/man1/postmaster.1.gz (postmaster.1.gz) in auto mode
* Starting PostgreSQL 9.5 database server * Failed to issue method call: Unit [email protected] failed to load: No such file or directory. See system logs and 'systemctl status [email protected]' for details.
[fail]
invoke-rc.d: initscript postgresql, action "start" failed.
dpkg: error processing package postgresql-9.5 (--configure):
subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of postgresql-contrib-9.5:
postgresql-contrib-9.5 depends on postgresql-9.5 (= 9.5.7-1.pgdg14.04+1); however:
Package postgresql-9.5 is not configured yet.
dpkg: error processing package postgresql-contrib-9.5 (--configure):
dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
Errors were encountered while processing:
postgresql-9.5
postgresql-contrib-9.5
E: Sub-process /usr/bin/dpkg returned an error code (1)
除此之外，当我尝试连接时，psql出现了另一个错误：
psql: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
当我想用创建新数据库时也会发生这种情况createdb example，因此我尝试了此解决方案所以回答，但错误仍然存在。
这是来自dpkg -l "postgresql*"
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-========================-=================-=================-=====================================================
un postgresql-7.4 <none> <none> (no description available)
un postgresql-8.0 <none> <none> (no description available)
un postgresql-9.1 <none> <none> (no description available)
iF postgresql-9.5 9.5.7-1.pgdg14.04 amd64 object-relational SQL database, version 9.5 server
un postgresql-client <none> <none> (no description available)
ii postgresql-client-9.5 9.5.7-1.pgdg14.04 amd64 front-end programs for PostgreSQL 9.5
ii postgresql-client-common 182.pgdg14.04+1 all manager for multiple PostgreSQL client versions
ii postgresql-common 182.pgdg14.04+1 all PostgreSQL database-cluster manager
un postgresql-contrib <none> <none> (no description available)
iU postgresql-contrib-9.5 9.5.7-1.pgdg14.04 amd64 additional facilities for PostgreSQL
un postgresql-doc-9.5 <none> <none> (no description available)
un postgresql-doc-9.6 <none> <none> (no description available)
所以谁能向我解释一下这里发生了什么，以及如何解决这个问题，谢谢。