Multiple database connections

suggest change

A transaction acts on a single database connection. If you have multiple class-specific databases, the transaction will not protect interaction among them. One workaround is to begin a transaction on each class whose models you alter:

Student.transaction do
  Course.transaction do
    course.enroll(student)
    student.units += course.units
  end
end

This is a poor solution, but fully distributed transactions are beyond the scope of ActiveRecord.

Found a mistake? Have a question or improvement idea? Let me know.

ActiveRecord transactions:

* ActiveRecord Transactions

* Basic example

* Different ActiveRecord classes in a single transaction

* Multiple database connections

* save and destroy are automatically wrapped in a transaction

* Callbacks

* Rolling back a transaction

Table Of Contents

0 Getting started with Ruby on Rails

1 Routing

2 ActiveRecord

3 Views

4 ActiveRecord migrations

5 Rails best practices

6 Naming conventions

7 ActionCable

8 ActiveModel

9 User Authentication in Rails

10 ActiveRecord Associations

11 ActiveRecord validations

12 ActiveRecord Query Interface

13 ActionMailer

14 Rails generate commands

15 Configuration

16 I18N - internalization

17 Using Google Maps with Rails

18 File Uploads

19 Caching

20 ActionController

21 Configuration

22 Safe constantize

23 Rails 5

24 Authorization with CanCan

25 Mongoid

26 Gems

27 Change default timezone

28 Asset pipeline

29 Upgrading Rails

30 ActiveRecord locking

31 Debugging

32 Configure Angular with Rails

33 Rails logger

34 Prawn PDF

35 Rails API

36 Deploying a Rails app on Heroku

37 ActiveSupport

38 Form Helpers

39 ActiveRecord transactions

40 RSpec and Ruby on Rails

41 Decorator pattern

42 Elasticsearch

43 React with Rails

44 Rails cookbook

45 Multi-purpose ActiveRecord columns

46 Class organization

47 Shallow Routing

48 Model states AASM

49 Rails 5 API Authentication

50 Testing Rails Applications

51 Active Jobs

52 Rails frameworks over the years

53 Nested form

54 Factory Girl

55 CSV

56 Tools for code optimization and cleanup

57 ActiveJob

58 Active Model serializers

59 Rails Engine - Modular Rails

60 Single Table inheritance

61 ActiveRecord transactions

62 Turbolinks

63 Friendly ID

64 Securely storing authentications keys

65 Authenticate API using Devise

66 Integrating React.js with Rails using Hyperloop

67 Change a default Rails application environment

68 Reserved words

69 Rails-Engines

70 Adding an Amazon RDS

71 Payment features in Rails

72 Rails on docker

73 Contributors