Need Explainantion of ActiveRecord::Base.transaction

rubyonrails-talk
1

Dear All:

Any one can help me to explain what is it for:

[1] ActiveRecord::Base.transaction and Customer.transaction ?

[2] What is deferences ActiveRecord::Base.transaction and Customer.transaction ?

[3] Is it the same like Transaction Support?

[4] Any one can give me proof of concept of ActiveRecord::Base.transaction ?

Thank you very much for your time and help.

Best Regards, Reinhart

2

Dear All:

Any one can help me to explain what is it for:

[1] ActiveRecord::Base.transaction and Customer.transaction ?

Most of the time they are identical. They're different if
Customer.connection != ActiveRecord::Base.connection

[2] What is deferences ActiveRecord::Base.transaction and Customer.transaction ?

No idea what you are talking about

[3] Is it the same like Transaction Support?

they are for database transactions

[4] Any one can give me proof of concept of ActiveRecord::Base.transaction ?

Customer.transaction do    #do something end

Fred

3

Thank You Fred,

I need to know :

[1] When do I use Model_name.transaction and When do I use ActiveRecord::Base.transaction?

[2] I have related tables in database and they are depended one each other. And they need having transaction support in a method. Which is good ActiveRecord::Base.transaction or each name_model.transaction ?

[3] Any good reference article that can explain it detail? I cant get it in google. Only sample code, but not explain process in transaction.

Once Again, Thank you very much.

Reinhart

4

Thank You Fred,

I need to know :

[1] When do I use Model_name.transaction and When do I use ActiveRecord::Base.transaction?

[2] I have related tables in database and they are depended one each other. And they need having transaction support in a method. Which is good ActiveRecord::Base.transaction or each name_model.transaction ?

Unless you're playing with multiple databases they're all the same

[3] Any good reference article that can explain it detail? I cant get it in google. Only sample code, but not explain process in transaction.

Don't know about that. there's not really an awful lot to say, it's just a means of running some code inside a database transaction. If an exception is thrown it's rolled back, if not it's committed (there's a specific exception you can throw to just roll back, can't remember the name but it will be in the docs.

Fred

5

Unless you do something specific to override the default functionality, a model that inherits from ActiveRecord::Base inherits the db connection that it uses. Indirectly, this means that ALL the models that inherit from ARec::Base will use the same connection (again, barring a specific override).

The transaction method, as Fred explains, provides an explicit way to mark the beginning and end of a db transaction. The transaction is run in the context of the db connection. If you have not done anything to override the way that your model sets/gets its DB connection then there is absolutely no difference between using transaction on ARec::Base or any of the models that inherited from it.