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		<title>Latest from ChinaonRails's Ask</title>
		<link>http://chinaonrails.com/go/ask</link>
		<description>ChinaonRails | ChinaonRails are one of the very few China based web consultancies, who specialize in application development using RubyOnRails/Agile/Ajax.</description>
		<category>Technology</category>
		<language>zh_cn</language>
		<item>
			<title>又来问弱智问题了。 ... 2 replies</title>
			<link>http://chinaonrails.com/topic/view/3783.html</link>
			<comments>http://chinaonrails.com/topic/view/3783.html#reply</comments>
			<dc:creator>jinleileiking</dc:creator>
			<author>jinleileiking</author>
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			<category>Ask</category>
			<description>
			存储blog内容的话，除了XML方式还有其他比较好的方式么？&lt;br /&gt;
&lt;br /&gt;
我就是想把我的blog内容存下来，以后我的BLOG升级了，一导入，以前的记录就还有，目前是想在网页上做个按钮，一点，就将记录转成XML文件存在硬盘，然后我重新部署网站，再一点，将以前的XML转为数据库，&lt;br /&gt;
&lt;br /&gt;
也就是个网络数据库备份，恢复问题，我在heroku部署，heroku会提供这种数据库备份恢复功能么？要是能提供就太好了。
			</description>
			<pubDate>Fri, 12 Mar 2010 12:42:04 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3783.html</guid>
		</item>
		<item>
			<title>求高手给个rails 所见即所得的编译器插件。 ... 7 replies</title>
			<link>http://chinaonrails.com/topic/view/3778.html</link>
			<comments>http://chinaonrails.com/topic/view/3778.html#reply</comments>
			<dc:creator>jinleileiking</dc:creator>
			<author>jinleileiking</author>
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			<category>Ask</category>
			<description>
			做blog用，有哪些加粗啊，粘贴个图片啊什么的，&lt;br /&gt;
&lt;br /&gt;
另外请教一下贴图片是怎么实现的？我把电脑的图片贴上，怎么也得给图片安个家吧，把jpeg加入mysql？
			</description>
			<pubDate>Wed, 10 Mar 2010 12:40:39 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3778.html</guid>
		</item>
		<item>
			<title>acts_as_archive 可以在windows下使吗？ ... 7 replies</title>
			<link>http://chinaonrails.com/topic/view/3767.html</link>
			<comments>http://chinaonrails.com/topic/view/3767.html#reply</comments>
			<dc:creator>邢星</dc:creator>
			<author>邢星</author>
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			<category>Ask</category>
			<description>
			我的开发环境是Ubuntu ,acts_as_archive是一个软删除的gem包 ,它在开发环境中一些正常&lt;br /&gt;
&lt;br /&gt;
产品环境只能用windows的server产品，是我安装这个gem后 提示 找不到&lt;br /&gt;
       lib/acts_as_archive/base&lt;br /&gt;
&lt;br /&gt;
好像还和另一个叫 require 的gem 有关... &lt;br /&gt;
各路大哥有请解惑
			</description>
			<pubDate>Wed, 03 Mar 2010 10:30:06 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3767.html</guid>
		</item>
		<item>
			<title>请教flex+webORB交互的问题 ... 1 reply</title>
			<link>http://chinaonrails.com/topic/view/3763.html</link>
			<comments>http://chinaonrails.com/topic/view/3763.html#reply</comments>
			<dc:creator>byderek</dc:creator>
			<author>byderek</author>
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			<category>Ask</category>
			<description>
			我后台语言是rails，用ruby script/plugin install http://themidnightcoders.net:8089/svn/weborb安装最新的webORB但是一运行项目就会出现如下错误&lt;br /&gt;
C:\Ruby\bin\ruby.exe -e STDOUT.sync=true;STDERR.sync=true;load($0=ARGV.shift) D:/Workspace/mytest/script/server -p 3000 -b 127.0.0.1 -e development&lt;br /&gt;
=&amp;gt; Booting WEBrick&lt;br /&gt;
=&amp;gt; Rails 2.3.5 application starting on http://127.0.0.1:3000&lt;br /&gt;
C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:105:in `const_missing': uninitialized constant Rails::Plugin::Dependencies (NameError)&lt;br /&gt;
	from D:/Workspace/mytest/vendor/plugins/weborb/init.rb:30:in `evaluate_init_rb'&lt;br /&gt;
	from C:/Ruby/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/rails/plugin.rb:158:in `evaluate_init_rb'&lt;br /&gt;
	from C:/Ruby/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/core_ext/kernel/reporting.rb:11:in `silence_warnings'&lt;br /&gt;
	from C:/Ruby/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/rails/plugin.rb:154:in `evaluate_init_rb'&lt;br /&gt;
	from C:/Ruby/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/rails/plugin.rb:48:in `load'&lt;br /&gt;
	from C:/Ruby/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/rails/plugin/loader.rb:38:in `load_plugins'&lt;br /&gt;
	from C:/Ruby/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/rails/plugin/loader.rb:37:in `each'&lt;br /&gt;
	from C:/Ruby/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/rails/plugin/loader.rb:37:in `load_plugins'&lt;br /&gt;
	 ... 12 levels...&lt;br /&gt;
	from C:/Ruby/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'&lt;br /&gt;
	from D:/Workspace/mytest/script/server:3&lt;br /&gt;
	from -e:1:in `load'&lt;br /&gt;
	from -e:1&lt;br /&gt;
&lt;br /&gt;
Process finished with exit code 1&lt;br /&gt;
知道的请告诉我是什么原因，谢谢
			</description>
			<pubDate>Fri, 26 Feb 2010 15:49:50 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3763.html</guid>
		</item>
		<item>
			<title>中文乱数排序,但标点符号位置固定 ... 3 replies</title>
			<link>http://chinaonrails.com/topic/view/3762.html</link>
			<comments>http://chinaonrails.com/topic/view/3762.html#reply</comments>
			<dc:creator>cor</dc:creator>
			<author>cor</author>
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			<category>Ask</category>
			<description>
			一段文字乱数排序,可以用这样的方式来执行：&lt;br /&gt;
&amp;gt;&amp;gt; a = "这是一段文，并且可以有“标点”以及“符号”。"&lt;br /&gt;
=&amp;gt; "这是一段文，并且可以有“标点”以及“符号”。"&lt;br /&gt;
&amp;gt;&amp;gt; a.split('').sort{rand(a.size) - 1}.join&lt;br /&gt;
=&amp;gt; "可及。这“符，“点文以有一是以标段并””且号"&lt;br /&gt;
&amp;gt;&amp;gt; a.split('').sort{rand(a.size) - 1}.join&lt;br /&gt;
=&amp;gt; "。有“这标并段点，号以可及””是“且符以一文"&lt;br /&gt;
&amp;gt;&amp;gt; a.split('').sort{rand(a.size) - 1}.join&lt;br /&gt;
=&amp;gt; "文。“符这标段”且号是并以可“”点有一及，以"&lt;br /&gt;
&amp;gt;&amp;gt; a.split('').sort{rand(a.size) - 1}.join&lt;br /&gt;
=&amp;gt; "。一“是且这标文“段”有并及，符以号点”以可"&lt;br /&gt;
&amp;gt;&amp;gt; a.split('').sort{rand(a.size) - 1}.join&lt;br /&gt;
=&amp;gt; "有”。是“这点，”且以以及段符“文并号标一可"&lt;br /&gt;
&lt;br /&gt;
全部随机排序的方式下，&lt;br /&gt;
连标点符号也一起随机排序，&lt;br /&gt;
会造成标点符号不合逻辑的情况。&lt;br /&gt;
避免此情况，就是要把标点符号“定位”，&lt;br /&gt;
然后才把其他文字做随机排序。&lt;br /&gt;
&lt;br /&gt;
所以不晓得要用怎样的方式，&lt;br /&gt;
可以把 “，。” 等标点符号记住该固定位置，&lt;br /&gt;
其他文字才做乱数排序填入标点符号之间？
			</description>
			<pubDate>Fri, 26 Feb 2010 10:24:31 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3762.html</guid>
		</item>
		<item>
			<title>大家有没有想创业的，谈谈想法 ... 4 replies</title>
			<link>http://chinaonrails.com/topic/view/3756.html</link>
			<comments>http://chinaonrails.com/topic/view/3756.html#reply</comments>
			<dc:creator>chengdh</dc:creator>
			<author>chengdh</author>
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			<category>Ask</category>
			<description>
			公司在技术上想基于rails&lt;br /&gt;
业务上想做一些在线的业务应用，目前瞄准小的物流企业的业务管理&lt;br /&gt;
有志同道和的，谈谈看法
			</description>
			<pubDate>Wed, 24 Feb 2010 16:19:00 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3756.html</guid>
		</item>
		<item>
			<title>migrate 生成的表不能输入中文 ... 1 reply</title>
			<link>http://chinaonrails.com/topic/view/3755.html</link>
			<comments>http://chinaonrails.com/topic/view/3755.html#reply</comments>
			<dc:creator>uuhui</dc:creator>
			<author>uuhui</author>
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			<category>Ask</category>
			<description>
			rake db:migrate 生成的表为何只能输入英文不能输入中文？
			</description>
			<pubDate>Wed, 24 Feb 2010 15:50:03 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3755.html</guid>
		</item>
		<item>
			<title>我的gem安装在哪里？ ... 6 replies</title>
			<link>http://chinaonrails.com/topic/view/3753.html</link>
			<comments>http://chinaonrails.com/topic/view/3753.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			今天重新手工编译安装了ruby1.9，rubygems&lt;br /&gt;
出现一个问题，不知道rubygems安装位置，无法启动它&lt;br /&gt;
1、编译ruby&lt;br /&gt;
# ./configure  --prefix=/usr/local/ruby  &lt;br /&gt;
# sudo make  &lt;br /&gt;
# sudo make install   &lt;br /&gt;
环境变量设置&lt;br /&gt;
PATH="/usr/local/ruby/bin"  （增加了这个）&lt;br /&gt;
# sudo ruby /home/pt/setup.rb &lt;br /&gt;
也成功完成&lt;br /&gt;
后面来问题了&lt;br /&gt;
sudo gem update --system&lt;br /&gt;
 unable to execute /usr/bin/gem: No such file or directory&lt;br /&gt;
我找了半天，搞不清gem安装在哪里？估计需要增加设置一个重要的环境变量，请问，如何解决这个问题呢？
			</description>
			<pubDate>Tue, 23 Feb 2010 22:27:09 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3753.html</guid>
		</item>
		<item>
			<title>多个硬盘上ruby的执行问题 ... 1 reply</title>
			<link>http://chinaonrails.com/topic/view/3745.html</link>
			<comments>http://chinaonrails.com/topic/view/3745.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			我的sda是当前磁盘，sdb挂载在sda的/mnt/usb下面，&lt;br /&gt;
sda安装了ruby1.9.1没有安装gem&lt;br /&gt;
sdb安装了ruby1.8,rubygem1.3.5&lt;br /&gt;
sdb的ruby命令安装在/usr/bin/ruby，我使用下面的命令无法执行ruby程序：（按照逻辑，应该正常执行的）&lt;br /&gt;
&lt;br /&gt;
/mnt/usb/usr/bin/ruby  /mnt/usb/home/pt/stocks.rb&lt;br /&gt;
报错：no such file to load--open-uri (LoadError)&lt;br /&gt;
我的命令，指定通过sdb上的ruby执行一个位于sdb上的程序，从错误故障看，ruby调用了sda上的东东（我的sda没有安装open-uri)，这是不合逻辑的，设计有问题，还是我应该采取另一种方式下命令？&lt;br /&gt;
全部卸载sda\sdb，仅仅安装sdb（此时的sdb称为当前的sda），执行程序正常。&lt;br /&gt;
说明一个问题：ruby还是有小bug，该语言还需不断完善，细节上需要改进。
			</description>
			<pubDate>Sun, 21 Feb 2010 11:23:11 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3745.html</guid>
		</item>
		<item>
			<title>如何安装ruby最好？ ... 3 replies</title>
			<link>http://chinaonrails.com/topic/view/3744.html</link>
			<comments>http://chinaonrails.com/topic/view/3744.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			这几天，碰到问题，发现ruby1.9不支持fastercsv，于是重新卸载ruby\rubygems，手工安装ruby\rubygem&lt;br /&gt;
出了问题，我输入gem没有反应，必须输入gem1.8才有反应，于是又重新采用系统的apt安装，这下又出来新问题，不知问题以前可以运行的程序，现在又不能运行了，有个库出了问题，`require': no such file to load -- open-uri (LoadError)&lt;br /&gt;
气死我了。&lt;br /&gt;
我发现rubygem被ubuntu官方打包成1.8（或称为1.9），实际上rubygem的官方最高版本是1.3.5，有人也反应ubuntu官方打包版有小问题（本人使用ubuntu的实际经验也有体会，ubuntu官方安装包有时候比手工编译安装差，举个影响大的例子，我曾经用官方的virtualbox，虚拟xp的时候无法使用usb，网银受到影响，最后用virtualbox的闭源二进制版本手工编译安装，成功使用usb网银），请问，究竟如何安装ruby，在运行程序的时候碰到的问题最小？
			</description>
			<pubDate>Sat, 20 Feb 2010 21:20:36 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3744.html</guid>
		</item>
		<item>
			<title>ruby对csv文件的操作 ... 1 reply</title>
			<link>http://chinaonrails.com/topic/view/3743.html</link>
			<comments>http://chinaonrails.com/topic/view/3743.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			有这样的一个数据文件：&lt;br /&gt;
"1",17.01,18.61,1.69&lt;br /&gt;
"2",7.65,8.17,0.74&lt;br /&gt;
"3",12.88,13.98,1.15&lt;br /&gt;
"4",8.02,8.73,0.7&lt;br /&gt;
"5",12.1,12.9,0.91&lt;br /&gt;
我想将它读取出来，用一个数组来装，arry[0][0]为1，arry[0][1]为17.01,以此类推，好像ruby本身的方法不行，&lt;br /&gt;
我用arr=IO.readlines("/home/pt/data.csv","r")&lt;br /&gt;
发现arr这个数组按照字节的acsii码来理解数据的。&lt;br /&gt;
并且ruby将第一行理解成&lt;br /&gt;
"\"1\",\"600133\",17.01,18.61,1.69,25181943\n\n"&lt;br /&gt;
arr[0][0]居然是34，arr[0][0].chr才是\,arr[0][1].chr才是1。&lt;br /&gt;
这跟我的想象差太远了，请问，ruby有自身的方法做到我的想法吗？
			</description>
			<pubDate>Sat, 20 Feb 2010 15:29:54 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3743.html</guid>
		</item>
		<item>
			<title>如何在写入文件数据时进行换行？ ... 2 replies</title>
			<link>http://chinaonrails.com/topic/view/3742.html</link>
			<comments>http://chinaonrails.com/topic/view/3742.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			下面的代码，将test.csv文件每行的前5个数据全部提取出来，存放在testback.csv，文件可以运行，但是testback.csv文件没有换行，没有读完5个数据后，重新开始一行，全部练成了一行，请问，如何解决这个问题？&lt;br /&gt;
io=open("/home/pt/test.csv","r")&lt;br /&gt;
ioback=open("/home/pt/testback.csv","w")&lt;br /&gt;
while line=io.gets&lt;br /&gt;
   ioput=line[0,5]&lt;br /&gt;
   ioback.write(ioput)&lt;br /&gt;
end
			</description>
			<pubDate>Sat, 20 Feb 2010 11:36:40 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3742.html</guid>
		</item>
		<item>
			<title>ruby对多维数组的操作？ ... 1 reply</title>
			<link>http://chinaonrails.com/topic/view/3741.html</link>
			<comments>http://chinaonrails.com/topic/view/3741.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			test.csv是一个csv文件，每行n个字段，一共m行&lt;br /&gt;
require 'csv'&lt;br /&gt;
infile = "/home/pt/test.csv"&lt;br /&gt;
data = CSV.read(infile)&lt;br /&gt;
这样做以后data成了一个多维数组，如何得到这个数组的维度参数，也就是n,m的具体数值。&lt;br /&gt;
如何获得m列的最大值？n行的最大值？&lt;br /&gt;
ruby有现成的方法吗？&lt;br /&gt;
我自己编程用多层循环也可以做到，但是有现成的方法更好。
			</description>
			<pubDate>Fri, 19 Feb 2010 22:27:02 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3741.html</guid>
		</item>
		<item>
			<title>undefined method `require_gem' for main:Object ... no reply</title>
			<link>http://chinaonrails.com/topic/view/3740.html</link>
			<comments>http://chinaonrails.com/topic/view/3740.html#reply</comments>
			<dc:creator>kezhon</dc:creator>
			<author>kezhon</author>
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			<category>Ask</category>
			<description>
			在Ruby on Rails开发电子商务网站一书中的Emporium网络书店的案例中，启动服务器加载源代码时发生如题的提示，有谁知道是怎么回事吗？&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
D:\prog\src\Beginning_Ruby_on_Rails_E_Commerce_From_Novice_to_Professional-3200\&lt;br /&gt;
chapter13\chapter13&amp;gt;mongrel_rails start -p 3001&lt;br /&gt;
** Starting Mongrel listening at 0.0.0.0:3001&lt;br /&gt;
** Starting Rails with development environment...&lt;br /&gt;
D:/prog/src/Beginning_Ruby_on_Rails_E_Commerce_From_Novice_to_Professional-3200/&lt;br /&gt;
chapter13/chapter13/config/boot.rb:25:Warning: Gem::SourceIndex#search support f&lt;br /&gt;
or String patterns is deprecated, use #find_name&lt;br /&gt;
D:/prog/src/Beginning_Ruby_on_Rails_E_Commerce_From_Novice_to_Professional-3200/&lt;br /&gt;
chapter13/chapter13/config/boot.rb:28: undefined method `require_gem' for main:O&lt;br /&gt;
bject (NoMethodError)&lt;br /&gt;
        from C:/Ruby186/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in&lt;br /&gt;
`gem_original_require'&lt;br /&gt;
        from C:/Ruby186/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in&lt;br /&gt;
`require'&lt;br /&gt;
        from D:/prog/src/Beginning_Ruby_on_Rails_E_Commerce_From_Novice_to_Profe&lt;br /&gt;
ssional-3200/chapter13/chapter13/config/environment.rb:11&lt;br /&gt;
        from C:/Ruby186/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in&lt;br /&gt;
`gem_original_require'&lt;br /&gt;
        from C:/Ruby186/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in&lt;br /&gt;
`require'&lt;br /&gt;
        from C:/Ruby186/lib/ruby/gems/1.8/gems/mongrel-1.1.5-x86-mswin32-60/bin/&lt;br /&gt;
../lib/mongrel/rails.rb:147:in `rails'&lt;br /&gt;
        from C:/Ruby186/lib/ruby/gems/1.8/gems/mongrel-1.1.5-x86-mswin32-60/bin/&lt;br /&gt;
mongrel_rails:113:in `cloaker_'&lt;br /&gt;
        from C:/Ruby186/lib/ruby/gems/1.8/gems/mongrel-1.1.5-x86-mswin32-60/bin/&lt;br /&gt;
../lib/mongrel/configurator.rb:149:in `call'&lt;br /&gt;
         ... 6 levels...&lt;br /&gt;
        from C:/Ruby186/lib/ruby/gems/1.8/gems/mongrel-1.1.5-x86-mswin32-60/bin/&lt;br /&gt;
../lib/mongrel/command.rb:212:in `run'&lt;br /&gt;
        from C:/Ruby186/lib/ruby/gems/1.8/gems/mongrel-1.1.5-x86-mswin32-60/bin/&lt;br /&gt;
mongrel_rails:281&lt;br /&gt;
        from C:/Ruby186/bin/mongrel_rails:19:in `load'&lt;br /&gt;
        from C:/Ruby186/bin/mongrel_rails:19
			</description>
			<pubDate>Fri, 19 Feb 2010 14:45:51 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3740.html</guid>
		</item>
		<item>
			<title>fastcsv不能使用？ ... 6 replies</title>
			<link>http://chinaonrails.com/topic/view/3739.html</link>
			<comments>http://chinaonrails.com/topic/view/3739.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			require 'fastercsv'&lt;br /&gt;
infile = "/home/pt/sqlite/test.csv"&lt;br /&gt;
data = fastercsv.open(infile,'r')&lt;br /&gt;
p   data[1][2]&lt;br /&gt;
上面的代码运行显示：&lt;br /&gt;
 no such file to load -- fastercsv (LoadError)&lt;br /&gt;
我明明使用sudo gem install  fastcsv,安装过了，在终端中使用  locate  fastcsv也可以看到输出，&lt;br /&gt;
/var/lib/gems/1.9.1/gems/fastercsv-1.5.1/test/tc_csv_writing.rb&lt;br /&gt;
/var/lib/gems/1.9.1/gems/fastercsv-1.5.1/test/tc_data_converters.rb&lt;br /&gt;
/var/lib/gems/1.9.1/gems/fastercsv-1.5.1/test/tc_encodings.rb&lt;br /&gt;
/var/lib/gems/1.9.1/gems/fastercsv-1.5.1/test/tc_features.rb&lt;br /&gt;
/var/lib/gems/1.9.1/gems/fastercsv-1.5.1/test/tc_headers.rb&lt;br /&gt;
/var/lib/gems/1.9.1/gems/fastercsv-1.5.1/test/tc_interface.rb&lt;br /&gt;
/var/lib/gems/1.9.1/gems/fastercsv-1.5.1/test/tc_row.rb&lt;br /&gt;
为何不能运行呢，找了半天，也没有发现原因，请指教。
			</description>
			<pubDate>Thu, 18 Feb 2010 11:46:29 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3739.html</guid>
		</item>
		<item>
			<title>gsub如何完成这个操作？ ... 3 replies</title>
			<link>http://chinaonrails.com/topic/view/3738.html</link>
			<comments>http://chinaonrails.com/topic/view/3738.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			如何用gsub将  "\"Allpages\"" 变换成 "Allpages"  ？
			</description>
			<pubDate>Wed, 17 Feb 2010 20:37:53 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3738.html</guid>
		</item>
		<item>
			<title>菜鸟问题：mysql导入csv数据 ... 4 replies</title>
			<link>http://chinaonrails.com/topic/view/3736.html</link>
			<comments>http://chinaonrails.com/topic/view/3736.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			以前用过access，它有一个简洁的数据导入方式，导入前，无须建立相应的数据表，access导入时可以将csv文件第一行的字符串作为表的字段。&lt;br /&gt;
我刚刚开始学习mysql，没有发现mysql有这样的功能，导入前需要准备一个表，设计好字段。（如果我的理解不对请指出）&lt;br /&gt;
现在，我想用ruby写一小段代码自动完成这个功能，发现，还有一定的难度。&lt;br /&gt;
1、用ruby读出文件第一行，并做解析，每个字符串赋值给一个数组元素。这个没有问题，我做到了&lt;br /&gt;
2、用sql建立表的字段，这个有点不好搞，无论人工很是自动&lt;br /&gt;
1）如果是人工，我可以看看csv文件，知道字段的类型，但是如果csv文件超级大，怎么办？INTEGER设置多长？字符类型设置多长？&lt;br /&gt;
如果不管不顾，设置长一点，太浪费空间了。&lt;br /&gt;
2）如果电脑自动识别，太费劲了，ruby如何判断数据的类型？&lt;br /&gt;
我在网上用英文检索了一下，create table from csv ,extract field names from first line,发现似乎php\perl写脚本可以做到？没有学过这两个，看不懂，好像程序都很短就实现了，微软的access都做到了，我想应该是可行的。&lt;br /&gt;
请问，ruby可以做到吗？如何做到呢？
			</description>
			<pubDate>Wed, 17 Feb 2010 13:59:05 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3736.html</guid>
		</item>
		<item>
			<title>ruby调用shell ... 2 replies</title>
			<link>http://chinaonrails.com/topic/view/3735.html</link>
			<comments>http://chinaonrails.com/topic/view/3735.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			查到资料，ruby使用system或者exec方法可以调用shell。&lt;br /&gt;
下面的两段小程序，都可以执行&lt;br /&gt;
ruby1&lt;br /&gt;
#!/usr/local/bin/ruby&lt;br /&gt;
p open("/home/pt/sqlite/test.csv").readlines[0]&lt;br /&gt;
exec 'head /home/pt/sqlite/test.csv'&lt;br /&gt;
ruby2&lt;br /&gt;
#!/usr/local/bin/ruby&lt;br /&gt;
p open("/home/pt/sqlite/test.csv").readlines[0]&lt;br /&gt;
system  'head /home/pt/sqlite/test.csv'&lt;br /&gt;
但是ruby3&lt;br /&gt;
#!/usr/local/bin/ruby&lt;br /&gt;
p open("/home/pt/sqlite/test.csv").readlines[0]&lt;br /&gt;
exec 'head /home/pt/sqlite/test.csv'&lt;br /&gt;
system  'head /home/pt/sqlite/test.csv'&lt;br /&gt;
执行结果发现，system、exec方法只有一个执行，好像只有system执行了，不知道为什么？
			</description>
			<pubDate>Wed, 17 Feb 2010 13:15:59 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3735.html</guid>
		</item>
		<item>
			<title>ruby读取指定的行 ... 1 reply</title>
			<link>http://chinaonrails.com/topic/view/3733.html</link>
			<comments>http://chinaonrails.com/topic/view/3733.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			我的文件/home/pt/sqlite/test.csv&lt;br /&gt;
io=open("/home/pt/sqlite/test.csv")&lt;br /&gt;
p io.readline&lt;br /&gt;
运行后，读出了第一行的数据，如果想让它读出第10行，如何表达？
			</description>
			<pubDate>Wed, 17 Feb 2010 11:26:14 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3733.html</guid>
		</item>
		<item>
			<title>目录类的理解 ... 3 replies</title>
			<link>http://chinaonrails.com/topic/view/3730.html</link>
			<comments>http://chinaonrails.com/topic/view/3730.html#reply</comments>
			<dc:creator>luofeiyu</dc:creator>
			<author>luofeiyu</author>
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			<category>Ask</category>
			<description>
			这段代码可以输入目录下面的目录和文件&lt;br /&gt;
dir=Dir.open("/home/pt/Downloads")&lt;br /&gt;
while  name =dir.read&lt;br /&gt;
 p  name  &lt;br /&gt;
end&lt;br /&gt;
dir.close&lt;br /&gt;
为何我直接要求输出p dir.read就不行？&lt;br /&gt;
1  dir=Dir.open("/home/pt/Downloads")&lt;br /&gt;
2  p dir.read&lt;br /&gt;
3  dir.close&lt;br /&gt;
第一句建立了一个新的目录类，&lt;br /&gt;
第二句  让它全部输出呀&lt;br /&gt;
运行后的结果，只有一个  "."  ？&lt;br /&gt;
感觉ruby的类太难理解了。
			</description>
			<pubDate>Mon, 15 Feb 2010 10:30:50 +0800</pubDate>
			<guid>http://chinaonrails.com/topic/view/3730.html</guid>
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