Ruby on Rails中，执行dropdb命令时，数据库删除失败，检查点请求为何总是失败？

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我了解使用PostgreSQL数据库的基本知识，并且已经用它大约一年了，没有遇到任何重大问题。我无法通过文档或现有的Stack Overflow问题找到答案。但现在，我在Mac上的PostgreSQL数据库上遇到了一个问题，直接出现...。

我只知道使用postgres数据库的基础知识并且已经使用它大约一年没有任何重大问题我无法通过文档或现有的stackoverflow问题.

但是现在我遇到了一个问题,我在我的mac上的pg db上一直出现以下错误.我尝试使用安装成功的brew安装更新的postgres,但我认为在此过程中我创建了另一个问题.错误是在尝试启动db时：

LOG: database system shutdown was interrupted; last known up at 2015-10-04 11:04:08 EDT LOG: database system was not properly shut down; automatic recovery in progress LOG: redo starts at 0/6000090 LOG: record with zero length at 0/6001990 LOG: redo done at 0/6001960 LOG: last completed transaction was at log time 2015-10-04 10:56:33.121103-04 FATAL: could not open directory "pg_logical/snapshots": No such file or directory LOG: startup process (PID 12905) exited with exit code 1 LOG: aborting startup due to startup process failure

所以我按照说明here使用pg_resetxlog然后继续尝试“REINDEX,转储数据库,重新initdb,并重新加载数据库”每个pg文档9.4没有成功的结果.我只是在圈子里.

我可以从数据库开始,但我无法放弃它并重新开始.如果我运行dropdb dbname,我得到

dropdb: could not connect to database template1: could not connect to server: No such file or directory Is the server running locally and accepting connections on Unix domain socket "/tmp/.s.PGSQL.5432"?

但是因为跑完后我无法启动数据库

pg_resetxlog -f /usr/local/var/postgres

并且返回“事务日志重置”我运行

pg_ctl start -D /usr/local/var/postgres

得到

pg_ctl: another server might be running; trying to start server anyway server starting FATAL: lock file "postmaster.pid" already exists HINT: Is another postmaster (PID 13114) running in data directory "/usr/local/var/postgres"?

所以我跑了

ps auxwww | grep postgres

得到了

Travis 13127 0.0 0.0 2432772 660 s000 S+ 11:24AM 0:00.00 grep postgres Travis 13120 0.0 0.0 2468112 604 ?? Ss 11:21AM 0:00.00 postgres: stats collector process Travis 13119 0.0 0.0 2604776 1444 ?? Ss 11:21AM 0:00.00 postgres: autovacuum launcher process Travis 13118 0.0 0.0 2604776 732 ?? Ss 11:21AM 0:00.00 postgres: wal writer process Travis 13117 0.0 0.0 2612968 1776 ?? Ss 11:21AM 0:00.05 postgres: writer process Travis 13116 0.0 0.0 2604776 756 ?? Ss 11:21AM 0:00.00 postgres: checkpointer process Travis 13114 0.0 0.2 2604776 14576 ?? S 11:21AM 0:00.02 /usr/local/opt/postgresql/bin/postgres -D /usr/local/var/postgres -r /usr/local/var/postgres/server.log

所以我跑了

kill 13114

然后

ps auxwww | grep postgres

得到了

Travis 13139 0.0 0.0 2432772 652 s000 S+ 11:25AM 0:00.00 grep postgres

当然,此时如果我再次尝试启动数据库,我会进入同一个圈子.

现在,如果我跑

pg_resetxlog -f /usr/local/var/postgres

其次是

psql template1

并尝试删除数据库没有任何反应.

它是rails项目的数据库.所以,如果我跑

rake db:drop

我得到了另一个

PG::InternalError: ERROR: checkpoint request failed

它还说我检查过的服务器日志中有一个提示

生活：

tail -f /usr/local/var/postgres/server.log

要么：

tail /usr/local/var/postgres/server.log

得到

ERROR: could not open directory "pg_logical/snapshots": No such file or directory ERROR: could not open directory "pg_logical/snapshots": No such file or directory ERROR: could not open directory "pg_logical/snapshots": No such file or directory ERROR: could not open directory "pg_logical/snapshots": No such file or directory ERROR: could not open directory "pg_logical/snapshots": No such file or directory ERROR: could not open directory "pg_logical/snapshots": No such file or directory ERROR: could not open directory "pg_logical/snapshots": No such file or directory ERROR: could not open directory "pg_logical/snapshots": No such file or directory ERROR: could not open directory "pg_logical/snapshots": No such file or directory ERROR: could not open directory "pg_logical/snapshots": No such file or directory

我不知道如何解决这个问题或者为什么它首先存在.搜索结果返回this但没有解决方案显示手动创建目录的完整路径

在这一点上,我很困惑,我认为我让事情变得更糟.

我检查了我的系统上的其他数据库,看到我的机器上的所有数据库现在都有同样的问题.另外我总是有1个grep postgres pid运行,我无法停止使用kill 13498或重启我的mac.

如何在不丢失机器上的所有数据库的情况下解决这个问题？

Brew信息postgres显示：

postgresql: stable 9.4.4 (bottled), devel 9.5alpha2 Object-relational database system www.postgresql.org/ Conflicts with: postgres-xc /usr/local/Cellar/postgresql/9.4.1_1 (2996 files, 40M) Poured from bottle /usr/local/Cellar/postgresql/9.4.4 (3014 files, 40M) * Poured from bottle From: github.com/Homebrew/homebrew/blob/master/Library/Formula/postgresql.rb ==> Dependencies Required: openssl ✔, readline ✔ ==> Options --32-bit Build 32-bit only --with-dtrace Build with DTrace support --with-python Build with python support --without-perl Build without Perl support --without-tcl Build without Tcl support --devel Install development version 9.5alpha2 ==> Caveats If builds of PostgreSQL 9 are failing and you have version 8.x installed, you may need to remove the previous version first. See: github.com/Homebrew/homebrew/issues/2510 To migrate existing data from a previous major version (pre-9.4) of PostgreSQL, see: www.postgresql.org/docs/9.4/static/upgrading.html To have launchd start postgresql at login: ln -sfv /usr/local/opt/postgresql/*.plist ~/Library/LaunchAgents Then to load postgresql now: launchctl load ~/Library/LaunchAgents/homebrew.mxcl.postgresql.plist Or, if you don't want/need launchctl, you can just run: postgres -D /usr/local/var/postgres

我正在跑优胜美地10.10.5

经过几个小时的研究后,我又重新开始工作而不会丢失任何数据库.

从我的其他mac我发现应该创建的目录应该在this帖子中引用需要创建的目录.我还创建了另外两个丢失的目录：

mkdir /usr/local/var/postgres/pg_logical mkdir /usr/local/var/postgres/pg_logical/mappings mkdir /usr/local/var/postgres/pg_logical/snapshots

接下来,我运行以下内容以获得良好的衡

brew update

和

brew doctor

然后我安装了酿造服务(info docs和article)

brew tap homebrew/services

接下来我运行以下内容,我从提示here派生,因为在故障排除/试错过程中,“pg_resetxlog -f /usr/local/var / postgres”命令开始抛出错误.

brew services stop postgresql

然后我试着平常

pg_ctl -D /usr/local/var/postgres start

一切都开始正常.由于现在安装了brew服务,我可以使用以下命令启动db：

brew services start postgresql

我仍然不确定为什么在创建目录后重新启动我的mac没有帮助.而且我也不确定为什么/如何/何时删除这些目录.而且我不确定究竟是什么造成了问题.但在做了我列出的事情后,一切正常.