Rails 4中遠程數據庫MySQL的模型錯誤

Question

我實現了與遠程MySQL數據庫的連接。

組態：

development:
  adapter: mysql2
  reconnect: false
  encoding: utf8
  database: All_clients
  username: <user>
  password: <pass>
  host: 127.0.0.1
  port: 3307
  pool: 5
  timeout: 5000

我創建了以下模型： rails g model Allclient date:datetime time:time number:float 。

做rake db:create我遇到了這個錯誤：

Mysql2::Error: Access denied for user 'user'@'192.168.%.%' to database 'Name_data_base': CREATE DATABASE `Name_data_base` DEFAULT CHARACTER SET `utf8` COLLATE `utf8_unicode_ci`
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/connection_adapters/abstract_mysql_adapter.rb:299:in `query'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/connection_adapters/abstract_mysql_adapter.rb:299:in `block in execute'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/connection_adapters/abstract_adapter.rb:473:in `block in log'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activesupport-4.2.1/lib/active_support/notifications/instrumenter.rb:20:in `instrument'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/connection_adapters/abstract_adapter.rb:467:in `log'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/connection_adapters/abstract_mysql_adapter.rb:299:in `execute'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/connection_adapters/mysql2_adapter.rb:231:in `execute'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/connection_adapters/abstract_mysql_adapter.rb:367:in `create_database'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/tasks/mysql_database_tasks.rb:16:in `create'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/tasks/database_tasks.rb:93:in `create'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/tasks/database_tasks.rb:107:in `block in create_current'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/tasks/database_tasks.rb:275:in `block in each_current_configuration'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/tasks/database_tasks.rb:274:in `each'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/tasks/database_tasks.rb:274:in `each_current_configuration'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/tasks/database_tasks.rb:106:in `create_current'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/gems/2.2.0/gems/activerecord-4.2.1/lib/active_record/railties/databases.rake:17:in `block (2 levels) in <top (required)>'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/task.rb:240:in `call'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/task.rb:240:in `block in execute'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/task.rb:235:in `each'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/task.rb:235:in `execute'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/task.rb:179:in `block in invoke_with_call_chain'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/monitor.rb:211:in `mon_synchronize'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/task.rb:172:in `invoke_with_call_chain'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/task.rb:165:in `invoke'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/application.rb:150:in `invoke_task'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/application.rb:106:in `block (2 levels) in top_level'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/application.rb:106:in `each'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/application.rb:106:in `block in top_level'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/application.rb:115:in `run_with_threads'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/application.rb:100:in `top_level'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/application.rb:78:in `block in run'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/application.rb:176:in `standard_exception_handling'
/home/ccar/.rbenv/versions/2.2.2/lib/ruby/2.2.0/rake/application.rb:75:in `run'
/home/ccar/.rbenv/versions/2.2.2/bin/rake:33:in `<main>'
Couldn't create database for {"adapter"=>"mysql2", "reconnect"=>false, "encoding"=>"utf8", "database"=>"Name_data_base", "username"=>"user", "password"=>"pass", "host"=>"127.0.0.1", "port"=>3307, "pool"=>5, "timeout"=>5000}
db/test.sqlite3 already exists

這是數據庫的層次結構，我想提取number值：

All_clients
 Tables
   client_products
     Columns
       date
       time
       number

我做錯了什么？

Answer 1

我沒有創建模型就找到了解決該問題的方法。

要從外部數據庫中提取數據，只需將其寫入rails console

sql= "SQL_QUERY"
out = ActiveRecord::Base.connection.select_all(sql)

如果這在控制台中有效，那么您可以確定它會在Rails應用程序中正常工作。 （控制器）

對於此示例，我有以下查詢：

SELECT number FROM All_clients.client_products limit 5

Limit 5提取前5個numbers 。

希望對其他人有幫助。