Ruby学习--用ActiveRecord操作数据库错误之连接1

控制台信息：

c:/ruby/lib/ruby/1.8/readbytes.rb:21:in `read': Invalid argument (Errno::EINVAL)
 from c:/ruby/lib/ruby/1.8/readbytes.rb:21:in `readbytes'
 from c:/ruby/lib/ruby/gems/1.8/gems/postgres-pr-0.4.0/lib/postgres-pr/message.rb:32:in `read'
 from c:/ruby/lib/ruby/gems/1.8/gems/postgres-pr-0.4.0/lib/postgres-pr/connection.rb:30:in `initialize'
 from c:/ruby/lib/ruby/gems/1.8/gems/postgres-pr-0.4.0/lib/postgres-pr/connection.rb:29:in `loop'
 from c:/ruby/lib/ruby/gems/1.8/gems/postgres-pr-0.4.0/lib/postgres-pr/connection.rb:29:in `initialize'
 from c:/ruby/lib/ruby/gems/1.8/gems/postgres-pr-0.4.0/lib/postgres-pr/postgres-compat.rb:23:in `new'
 from c:/ruby/lib/ruby/gems/1.8/gems/postgres-pr-0.4.0/lib/postgres-pr/postgres-compat.rb:23:in `initialize'
 from c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/connection_adapters/postgresql_adapter.rb:24:in `connect'
  ... 9 levels...
 from c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/base.rb:1490:in `initialize_without_callbacks'
 from c:/ruby/lib/ruby/gems/1.8/gems/activerecord-1.15.1/lib/active_record/callbacks.rb:225:in `initialize'
 from test.rb:17:in `new'
 from test.rb:17

看完有点莫名其妙，但可以肯定的是：错误来自数据库。找到PostgreSQl的日志：

2007-02-11 23:13:38 FATAL:  database "hello" does not exist
2007-02-11 23:18:48 FATAL:  database "hello" does not exist

原来如此，数据库名称不确，用SQLServer用惯了，难免出现这种大小写错误，立马改过"Hello"

ruby 代码

require 'rubygems'
require_gem 'activerecord'  # 请注意使用rubygems时候的声明方式

# 连接数据库，按需求填写各种参数。
ActiveRecord::Base.establish_connection(
:adapter => "postgresql",
:host => "localhost",
:username => "admin",
:password => "admin",
:database => "hello")

class Resource < ActiveRecord::Base # 开始ORM对应
  set_table_name 'resource' # 指定数据库名
end

# 插入一条数据
tab = Resource.new("id" => 8)
tab.id = 8
tab.name = 'ActiveRecord'
tab.save

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• 2007-02-11 23:44
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