ruby（rails) 程序如何 连接 各种远程数据库？

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ruby（rails) 程序如何 连接 各种远程数据库？,第1张

在使用Cookie.find等操作的时候，就会连接到database.yml中monitor_spider配置的数据库上操作。以前一直都这么用，没发现什么不妥。最近一个项目，由于启动的进程比较多，老是碰到数据库连接池链接获取超时的错误。

通过MySQL Client用命令:show processlist发现数据库连接数量一直居高不下，轻轻松松就上2k+的连接。通过读Rails框架的connection_pool.rb文件代码，发现在各模型中用establish_connection连接数据库会造成很大的问题。文件中类ConnectionHandler的establish_connection方法代码如下：Ruby代码 def establish_connection(name, spec) @connection_pools[name] = ConnectionAdapters::ConnectionPool.new(spec) end def establish_connection(name, spec)

@connection_pools[name] = ConnectionAdapters::ConnectionPool.new(spec)

require 'mysql'

class MysqlDb

# attr_accessor :host, :user, :pass, :database

def open(host=nil, user=nil, pass=nil, database=nil,port=3306)

@host =host

@user = user

@pass = pass

@database = database

@port = port

begin

@connection = Mysql.new(@host, @user, @pass, @database, @port)

rescue

puts "connect faild! an error has occurred: #{$!}" # 错误信息保存在特殊变量$!中。

try_again

end

end

def try_again

puts '------------------try again, if not modify, leave a blank---------------'

print "host: "

host=STDIN.gets.strip

@host = check_value(host,@host)

puts "---------------current host: #{@host}"

print "user: "

user =STDIN.gets.strip

@user = check_value(user,@user)

puts "---------------current user: #{@user}"

print "password: "

pass =STDIN.gets.strip

@pass = check_value(pass,@pass)

puts "---------------current password: #{@pass}"

print "database: "

database =STDIN.gets.strip

@database = check_value(database,@database)

puts "---------------current database: #{@database}"

print "port: "

port =STDIN.gets.strip

@port = check_value(port,@port)

open(@host, @user, @pass, @database, @port)

puts "---------------current port: #{@port}"

end

def check_value(value,returnvalue)

if value == ""

nil

else

returnvalue = value

end

return returnvalue

end

def iquery(sql)

field = []

@connection.query(sql).each do |data|

field <<data

end

field.to_a

end

def iexecute(sql)

@connection.query(sql)

end

def close

@connection.close

end

end

# useages

adb = MysqlDb.new

adb.open('127.0.0.1','root','zyq001122','hello_z','3307')

# result = db.query "insert into user value(7,\"lilY\",\"256y42\",\"#{Time.now.strftime("%Y-%m-%d %H:%M:%S")}\" )" # 插入记录

# result.each {|row| puts row}

num_of_records = adb.iquery ('select count(*) from user') #查询

puts num_of_records

#sql = "insert into user value(10,\"Hello-Kitty\",\"256y42\",\"#{Time.now.strftime("%Y-%m-%d %H:%M:%S")}\" )"# 数据操作

# sql = 'update user set name=\'jackjhons\' where uid=5 ' # 更新一条记录

#adb.iexecute(sql)

# adb.close