ActiveRecord and model question

[Srdjan Cengic]

Hy,

I have some table in my DB like following: Post(id, title, content, created_at, updated_at)

First question, what type ActiveRecord returns?
For example if i do something like: @posts = Post.all, through debugger i can see:

#<ActiveRecord::Relation
[#<Post id: 1, title: "My first post", content: "Zdravo, ovo je moj prvi post.", created_at: "2013-10-17 10:06:55", updated_at: "2013-10-17 10:06:55">,
#<Post id: 3, title: "My second post", content: "Zdravo, ovo je moj drugi post.", created_at: "2013-10-17 11:11:29", updated_at: "2013-10-17 11:11:29">,
#<Post id: 18, title: "My third post", content: "Dobar dan, ovo je moj treci post.", created_at: "2013-10-18 11:31:07",updated_at: "2013-10-18 11:31:07">]>

So this is array of hashes? or array of Post objects?

Second if i do something like:
@post = Post.first (this will return Post object?)

then through debugger i can do: @post.id
Here, i'm guessing, because each model is inherit from ActiveRecord::Base, ActiveRecord will create accessor for each column in table that represent model?
Because that i can write something like @post.id or @post.id = 100.
So internally ActiveRecord does something like attr_accessor :id for Post model? (and for every other column in posts table, attr_accesor: title, etc)

[Frederick Cheung]

On Saturday, October 19, 2013 7:33:12 PM UTC+1, Srdjan Cengic wrote:

Hy,

I have some table in my DB like following: Post(id, title, content, created_at, updated_at)

First question, what type ActiveRecord returns?
For example if i do something like: @posts = Post.all, through debugger i can see:

#<ActiveRecord::Relation
[#<Post id: 1, title: "My first post", content: "Zdravo, ovo je moj prvi post.", created_at: "2013-10-17 10:06:55", updated_at: "2013-10-17 10:06:55">,
#<Post id: 3, title: "My second post", content: "Zdravo, ovo je moj drugi post.", created_at: "2013-10-17 11:11:29", updated_at: "2013-10-17 11:11:29">,
#<Post id: 18, title: "My third post", content: "Dobar dan, ovo je moj treci post.", created_at: "2013-10-18 11:31:07",updated_at: "2013-10-18 11:31:07">]>

So this is array of hashes? or array of Post objects?

I n rails 3, this is an array of Post objects (on rails 4 it is an ActiveRecord::Relation, but you can still treat it as an array of Post objects)

 

Second if i do something like:
@post = Post.first (this will return Post object?)

Yes. 

then through debugger i can do: @post.id
Here, i'm guessing, because each model is inherit from ActiveRecord::Base, ActiveRecord will create accessor for each column in table that represent model?
Because that i can write something like @post.id or @post.id = 100.
So internally ActiveRecord does something like attr_accessor :id for Post model? (and for every other column in posts table, attr_accesor: title, etc)

ActiveRecord creates accessors for you (although they are not the same as the ones that would be created by attr_accessor)

Fred