Hello, Can someone kindly tell what the heck creating a relationship does in active record? I understand the idea of joining the tables and such. But how do I use it? Is it available in a scaffold? How about when I want to view a record and want to see all the joined data from the other table? Do I have to manually code the data I want from the other table? Does this automatically make the linked data available in the data object? Can we get real docs instead of API refs? Thanks, Phill
I''m sure i speak for everyone when i *highly* recommend that you have a look at getting the Agile book: http://www.pragmaticprogrammer.com/titles/rails/index.html. It''ll give you a good grounding in Rails and the concepts behind things like Active record. Steve Phillip Novess wrote:> Hello, > > Can someone kindly tell what the heck creating a relationship does in > active record? > > I understand the idea of joining the tables and such. But how do I use > it? Is it available in a scaffold? How about when I want to view a > record and want to see all the joined data from the other table? Do I > have to manually code the data I want from the other table? Does this > automatically make the linked data available in the data object? > > Can we get real docs instead of API refs? > > Thanks, > Phill > > _______________________________________________ > Rails mailing list > Rails@lists.rubyonrails.org > http://lists.rubyonrails.org/mailman/listinfo/rails > > >
Vince Puzzella
2006-May-09 17:06 UTC
[Rails] FireBug - Monitor AJAX/CSS/HTML/JS (an add-on for FireFox)
https://addons.mozilla.org/firefox/1843/>From the site:FireBug lets you explore the far corners of the DOM by keyboard or mouse. All of the tools you need to poke, prod, and monitor your JavaScript, CSS, HTML and Ajax are brought together into one seamless experience, including an error console, command line, and a variety of fun inspectors. Visit the FireBug website for documentation, screen shots, and discussion forums: http://www.joehewitt.com/software/firebug/ A quick overview of FireBug''s features: * Status bar icon shows you when there is an error in a web page * A console that shows errors from JavaScript and CSS * Log messages from JavaScript in your web page to the console (bye bye "alert debugging") * An JavaScript command line (no more "javascript:" in the URL bar) * Spy on XMLHttpRequest traffic * Inspect HTML source, computed style, events, layout and the DOM Works with: Firefox 1.5 - 3.0 ALL
You might want to start by looking at this screencast: http://media.rubyonrails.org/video/rails_take2_with_sound.mov Robert Phillip Novess wrote:> Hello, > > Can someone kindly tell what the heck creating a relationship does in > active record? > > I understand the idea of joining the tables and such. But how do I use > it? Is it available in a scaffold? How about when I want to view a > record and want to see all the joined data from the other table? Do I > have to manually code the data I want from the other table? Does this > automatically make the linked data available in the data object? > > Can we get real docs instead of API refs? > > Thanks, > Phill
Thanks. But that really doesn''t help. I have the book. I don''t see anything that clearly states what s the result of linking the tables. Are the columns from say table A available when I view a record from table B that references table A? Is my object now B.column1, B.column2, B.column3, A.column1 or what? If NOT then what''s the point of creating the link? Thanks, Phill On May 9, 2006, at 10:32 AM, Stephen Bartholomew wrote: I''m sure i speak for everyone when i *highly* recommend that you have a look at getting the Agile book: http://www.pragmaticprogrammer.com/titles/rails/index.html. It''ll give you a good grounding in Rails and the concepts behind things like Active record. Steve Phillip Novess wrote:> Hello, > Can someone kindly tell what the heck creating a relationship does in > active record? > I understand the idea of joining the tables and such. But how do I use > it? Is it available in a scaffold? How about when I want to view a > record and want to see all the joined data from the other table? Do I > have to manually code the data I want from the other table? Does this > automatically make the linked data available in the data object? > Can we get real docs instead of API refs? > Thanks, > Phill > _______________________________________________ > Rails mailing list > Rails@lists.rubyonrails.org > http://lists.rubyonrails.org/mailman/listinfo/rails_______________________________________________ Rails mailing list Rails@lists.rubyonrails.org http://lists.rubyonrails.org/mailman/listinfo/rails
See pages 233 and 237, they spell it out pretty clearly. Ken Phillip Novess wrote:> Thanks. But that really doesn''t help. I have the book. I don''t see > anything that clearly states what s the result of linking the tables. > > Are the columns from say table A available when I view a record from > table B that references table A? > > Is my object now B.column1, B.column2, B.column3, A.column1 or what? > If NOT then what''s the point of creating the link? > > Thanks, > Phill >
I don''t mean to sound rude, but you state that you have the book ... have you read it? Furthermore, have you ever built a database application before? Please don''t take offense, but if you answered no to these questions, then I think you''ll have some homework to do before you are ready to dive into building a rails app. It is stated quite clearly in the book, as well as the docs, that the result of declaring an association in a model is that the elements in the related model become available as methods of the class instance. The method will access a single object for belongs_to or has_one relationships, and an array of objects for has_many relationships. One last thing - You''ll get faster and more appropriate responses if you make your subject line meaningful. Especially on lists as busy as this, generic subjects will be glossed over more often than not. -Derrick Spell On May 9, 2006, at 1:48 PM, Phillip Novess wrote:> Thanks. But that really doesn''t help. I have the book. I don''t see > anything that clearly states what s the result of linking the tables. > > Are the columns from say table A available when I view a record > from table B that references table A? > > Is my object now B.column1, B.column2, B.column3, A.column1 or > what? If NOT then what''s the point of creating the link? > > Thanks, > Phill > > > > > On May 9, 2006, at 10:32 AM, Stephen Bartholomew wrote: > > I''m sure i speak for everyone when i *highly* recommend that you > have a look at getting the Agile book: http:// > www.pragmaticprogrammer.com/titles/rails/index.html. > > It''ll give you a good grounding in Rails and the concepts behind > things like Active record. > > Steve > > Phillip Novess wrote: >> Hello, >> Can someone kindly tell what the heck creating a relationship does >> in active record? >> I understand the idea of joining the tables and such. But how do I >> use it? Is it available in a scaffold? How about when I want to >> view a record and want to see all the joined data from the other >> table? Do I have to manually code the data I want from the other >> table? Does this automatically make the linked data available in >> the data object? >> Can we get real docs instead of API refs? >> Thanks, >> Phill >> _______________________________________________ >> Rails mailing list >> Rails@lists.rubyonrails.org >> http://lists.rubyonrails.org/mailman/listinfo/rails > _______________________________________________ > Rails mailing list > Rails@lists.rubyonrails.org > http://lists.rubyonrails.org/mailman/listinfo/rails > > _______________________________________________ > Rails mailing list > Rails@lists.rubyonrails.org > http://lists.rubyonrails.org/mailman/listinfo/rails >
You should be able to access a parent via a child object. For example:
class Parent < ActiveRecord::Base
has_many :children
end
class Child < ActiveRecord::Base
belongs_to :parent
end
The ''children'' table would have ''parent_id''
column referencing the
''parents'' table.
You can then reference the parent via the child:
child = Child.find(1)
child.parent.name -----> shows the parent''s name
The book does explain all this, but you may have to read through every
page as it''s not really a reference book (imo). The Rails recipes book
looks quite promising for a problem/solution approach.
Hope this helps,
Steve
Phillip Novess wrote:> Thanks. But that really doesn''t help. I have the book. I
don''t see
> anything that clearly states what s the result of linking the tables.
>
> Are the columns from say table A available when I view a record from
> table B that references table A?
>
> Is my object now B.column1, B.column2, B.column3, A.column1 or what? If
> NOT then what''s the point of creating the link?
>
> Thanks,
> Phill
>
>
>
>
> On May 9, 2006, at 10:32 AM, Stephen Bartholomew wrote:
>
> I''m sure i speak for everyone when i *highly* recommend that you
have a
> look at getting the Agile book:
> http://www.pragmaticprogrammer.com/titles/rails/index.html.
>
> It''ll give you a good grounding in Rails and the concepts behind
things
> like Active record.
>
> Steve
>
> Phillip Novess wrote:
>
>> Hello,
>> Can someone kindly tell what the heck creating a relationship does in
>> active record?
>> I understand the idea of joining the tables and such. But how do I use
>> it? Is it available in a scaffold? How about when I want to view a
>> record and want to see all the joined data from the other table? Do I
>> have to manually code the data I want from the other table? Does this
>> automatically make the linked data available in the data object?
>> Can we get real docs instead of API refs?
>> Thanks,
>> Phill
>> _______________________________________________
>> Rails mailing list
>> Rails@lists.rubyonrails.org
>> http://lists.rubyonrails.org/mailman/listinfo/rails
>
> _______________________________________________
> Rails mailing list
> Rails@lists.rubyonrails.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
>
> _______________________________________________
> Rails mailing list
> Rails@lists.rubyonrails.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
>
>
>
Thanks. That makes sense. child.parent.name. Ah ha.
Thanks,
Phill
On May 9, 2006, at 12:13 PM, Stephen Bartholomew wrote:
You should be able to access a parent via a child object. For example:
class Parent < ActiveRecord::Base
has_many :children
end
class Child < ActiveRecord::Base
belongs_to :parent
end
The ''children'' table would have ''parent_id''
column referencing the
''parents'' table.
You can then reference the parent via the child:
child = Child.find(1)
child.parent.name -----> shows the parent''s name
The book does explain all this, but you may have to read through every
page as it''s not really a reference book (imo). The Rails recipes book
looks quite promising for a problem/solution approach.
Hope this helps,
Steve
Phillip Novess wrote:> Thanks. But that really doesn''t help. I have the book. I
don''t see
> anything that clearly states what s the result of linking the tables.
> Are the columns from say table A available when I view a record from
> table B that references table A?
> Is my object now B.column1, B.column2, B.column3, A.column1 or what?
> If NOT then what''s the point of creating the link?
> Thanks,
> Phill
> On May 9, 2006, at 10:32 AM, Stephen Bartholomew wrote:
> I''m sure i speak for everyone when i *highly* recommend that you
have
> a look at getting the Agile book:
> http://www.pragmaticprogrammer.com/titles/rails/index.html.
> It''ll give you a good grounding in Rails and the concepts behind
> things like Active record.
> Steve
> Phillip Novess wrote:
>> Hello,
>> Can someone kindly tell what the heck creating a relationship does in
>> active record?
>> I understand the idea of joining the tables and such. But how do I
>> use it? Is it available in a scaffold? How about when I want to view
>> a record and want to see all the joined data from the other table?
>> Do I have to manually code the data I want from the other table? Does
>> this automatically make the linked data available in the data object?
>> Can we get real docs instead of API refs?
>> Thanks,
>> Phill
>> _______________________________________________
>> Rails mailing list
>> Rails@lists.rubyonrails.org
>> http://lists.rubyonrails.org/mailman/listinfo/rails
> _______________________________________________
> Rails mailing list
> Rails@lists.rubyonrails.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
> _______________________________________________
> Rails mailing list
> Rails@lists.rubyonrails.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
_______________________________________________
Rails mailing list
Rails@lists.rubyonrails.org
http://lists.rubyonrails.org/mailman/listinfo/rails
Derrick, Yeah I''ve made my living building web applications for the past 8 years. However, I use PHP and Oracle on a daily basis NOT Rails. I don''t think anybody would argue that there is anything quite like Rails. That''s what makes it interesting. Also. I''m doing this in addition to my daily work in PHP so I get a little confused. Ruby is 100% object oriented, PHP is not. I''m still trying to sink my head around that concept alone. So please bare with me. Sometimes I just need to ask what is meant by something otherwise what''s the point of a list right? I guess I''m spoiled with the excellent documentation resources at php.net. Thanks for the help. Very good points. Thanks, Phill On May 9, 2006, at 12:13 PM, Derrick Spell wrote: I don''t mean to sound rude, but you state that you have the book ... have you read it? Furthermore, have you ever built a database application before? Please don''t take offense, but if you answered no to these questions, then I think you''ll have some homework to do before you are ready to dive into building a rails app. It is stated quite clearly in the book, as well as the docs, that the result of declaring an association in a model is that the elements in the related model become available as methods of the class instance. The method will access a single object for belongs_to or has_one relationships, and an array of objects for has_many relationships. One last thing - You''ll get faster and more appropriate responses if you make your subject line meaningful. Especially on lists as busy as this, generic subjects will be glossed over more often than not. -Derrick Spell On May 9, 2006, at 1:48 PM, Phillip Novess wrote:> Thanks. But that really doesn''t help. I have the book. I don''t see > anything that clearly states what s the result of linking the tables. > > Are the columns from say table A available when I view a record from > table B that references table A? > > Is my object now B.column1, B.column2, B.column3, A.column1 or what? > If NOT then what''s the point of creating the link? > > Thanks, > Phill > > > > > On May 9, 2006, at 10:32 AM, Stephen Bartholomew wrote: > > I''m sure i speak for everyone when i *highly* recommend that you have > a look at getting the Agile book: > http://www.pragmaticprogrammer.com/titles/rails/index.html. > > It''ll give you a good grounding in Rails and the concepts behind > things like Active record. > > Steve > > Phillip Novess wrote: >> Hello, >> Can someone kindly tell what the heck creating a relationship does in >> active record? >> I understand the idea of joining the tables and such. But how do I >> use it? Is it available in a scaffold? How about when I want to view >> a record and want to see all the joined data from the other table? >> Do I have to manually code the data I want from the other table? Does >> this automatically make the linked data available in the data object? >> Can we get real docs instead of API refs? >> Thanks, >> Phill >> _______________________________________________ >> Rails mailing list >> Rails@lists.rubyonrails.org >> http://lists.rubyonrails.org/mailman/listinfo/rails > _______________________________________________ > Rails mailing list > Rails@lists.rubyonrails.org > http://lists.rubyonrails.org/mailman/listinfo/rails > > _______________________________________________ > Rails mailing list > Rails@lists.rubyonrails.org > http://lists.rubyonrails.org/mailman/listinfo/rails >_______________________________________________ Rails mailing list Rails@lists.rubyonrails.org http://lists.rubyonrails.org/mailman/listinfo/rails
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