小编Tia*_*ian的帖子

当我尝试清理我的rails版本时 sudo gem cleanup rails

我收到以下错误:

Cleaning up installed gems...
Attempting to uninstall rails-2.3.5
Unable to uninstall rails-2.3.5:
Gem::InstallError: cannot uninstall, check `gem list -d rails`
Attempting to uninstall rails-1.2.6
Unable to uninstall rails-1.2.6:
Gem::InstallError: cannot uninstall, check `gem list -d rails`

gem list -d rails 结果是:

rails (2.3.8, 2.3.5, 1.2.6)
  Author: David Heinemeier Hansson
  Rubyforge: http://rubyforge.org/projects/rails
  Homepage: http://www.rubyonrails.org
  Installed at (2.3.8): /Library/Ruby/Gems/1.8
               (2.3.5): /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8
               (1.2.6): /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/gems/1.8

  Web-application framework with template engine, control-flow layer,
  and ORM.

谁知道什么是错的？

有谁知道将数据库条目转换为XML的任何好方法？

即如果我有一个名为"Users"的表,其字段为"first_name","age","last_name",我想将表转换为:

<Users>
  <first_name>Papa</first_name>
  <age>50</age>
  <last_name>John</last_name>
</Users>

我通过MacPorts安装了PostgreSQL.但是,/opt/local/lib/postgresql84/bin我无法执行任何pg命令.有谁知道我做错了什么？