Use Activerecord from Rails

ActiveRecord is the best ORM library I have ever seen. Apart from DB2, ActiveRecord supports all mainstream databases. If you want to know how to use Activerecord and please follow me separately.

 

Introduce my system environment:

OS: windows2003

DataBase: Oracle10g

Ruby: 1.8.7 (patchlevel 0) [i386-mswin32]

Activerecord: 2.2.2

Activerecord-oracle_enhanced-adapter: 1.1.8.

Ruby-oci8: 1.0.3.

 

Preparations:

1. Install ruby. Needless to say

2. install activerecord and gem install activerecord

3. install adapter, gem install activerecord-oracle_enhanced-adapter

4. Create a test directory mkdir dbtest

OK, that's all

 

Create a rb file with the following content:

 

Ruby code

1. Require 'rubygems'
2. Require 'Active _ record'
4. ActiveRecord: Base. establish_connection (
5. : Adapter => 'oracle _ enabled ',
6. : Database => 'test', # oracle service name
7. : Username => 'system ',
8. : Password => 'system ')

require 'rubygems'require 'active_record'ActiveRecord::Base.establish_connection(:adapter  => 'oracle_enhanced',:database => 'test',   #oracle service name:username => 'system',:password => 'system')  

 

 

You can also separately store the database configuration information in a file to create a file database. yml with the following content:

 

Ruby code

1. Adapter: oracle_enhanced
2. Database: test
3. Username: system
4. Password: system

adapter:  oracle_enhanceddatabase: testusername: systempassword: system

 

Change the rb file

 

Ruby code

1. Require 'rubygems'
2. Require 'Active _ record'
3. Require 'yaml'
5. Dbconfig = YAML: load (File. open ('database. yml '))
6. ActiveRecord: Base. establish_connection (dbconfig)

require 'rubygems'require 'active_record'require 'yaml'dbconfig = YAML::load(File.open('database.yml'))ActiveRecord::Base.establish_connection(dbconfig)

Try it

 

Ruby code

1. Require 'rubygems'
2. Require 'Active _ record'
3. Require 'yaml'
5. Dbconfig = YAML: load (File. open ('database. yml '))
6. ActiveRecord: Base. establish_connection (dbconfig)
8. Class User <ActiveRecord: Base
9. Set_table_name "my_user"
10. End
12. Puts User. count

require 'rubygems'require 'active_record'require 'yaml'dbconfig = YAML::load(File.open('database.yml'))ActiveRecord::Base.establish_connection(dbconfig)class User < ActiveRecord::Baseset_table_name "my_user"endputs User.count  

 

If you want to add logs to activerecord, you can do this.

 

Ruby code

1. Require 'rubygems'
2. Require 'Active _ record'
3. Require 'yaml'
4. Require 'logger'
6. Dbconfig = YAML: load (File. open ('database. yml '))
7. ActiveRecord: Base. establish_connection (dbconfig)
8. ActiveRecord: Base. logger = Logger. new (File. open ('database. log', 'A '))
10. Class User <ActiveRecord: Base
11. Set_table_name "my_user"
12. End
14. Puts User. count

require 'rubygems'require 'active_record'require 'yaml'require 'logger'dbconfig = YAML::load(File.open('database.yml'))ActiveRecord::Base.establish_connection(dbconfig)ActiveRecord::Base.logger = Logger.new(File.open('database.log', 'a'))class User < ActiveRecord::Baseset_table_name "my_user"endputs User.count  

 

In this way, a database. log file is generated.

 

OK. Let's get there today.