Hi everybody
I am totally new to rails and I am trying to start a
tiny project to get familiar with rails. But I already
got my first problem and I would be happy if somebody
could point me in the best and cleanest direction.
I am trying to develop a small gallery app. Since I
would like to add more features in future I am trying
to design a clean OO architecture of my models:
The base object should be NODE. All other objects
extend NODE, those are GALLERY and IMAGE (a GALLERY
consists of 0..* IMAGEs). Each NODE has an owner
(user_id) plus some default fields like created_on and
updated_on. Futhermore there is an object COMMENT
which can be attached to any object that extends NODE
(belongs_to NODE).
According to this design I modeled the db schema as
follows:
CREATE TABLE `nodes` (
`id` int(11) NOT NULL auto_increment,
`user_id` int(11) NOT NULL default ''0'',
`created_on` timestamp NOT NULL default
CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
`updated_on` timestamp NOT NULL default ''0000-00-00
00:00:00'', PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
DROP TABLE IF EXISTS `galleries`;
CREATE TABLE `galleries` (
`id` int(11) NOT NULL auto_increment,
`node_id` int(11) NOT NULL default ''0'',
`user_id` int(11) NOT NULL default ''0'',
`title` varchar(255) NOT NULL default '''',
`descr` text NOT NULL,
PRIMARY KEY (`id`),
KEY `user_key` (`user_id`),
KEY `node_key` (`node_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
DROP TABLE IF EXISTS `images`;
CREATE TABLE `images` (
`id` int(11) NOT NULL auto_increment,
`user_id` int(11) NOT NULL default ''0'',
`gallery_id` int(11) NOT NULL default ''0'',
`node_id` int(11) NOT NULL default ''0'',
`title` varchar(255) NOT NULL default '''',
`descr` text NOT NULL,
PRIMARY KEY (`id`),
KEY `gallery_key` (`gallery_id`),
KEY `node_key` (`node_id`),
KEY `user_key` (`user_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
CREATE TABLE `comments` (
`id` int(11) NOT NULL default ''0'',
`node_id` int(11) NOT NULL default ''0'',
`user_id` int(11) NOT NULL default ''0'',
`title` varchar(255) NOT NULL default '''',
`body` text NOT NULL,
`created_on` timestamp NOT NULL default
CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
`updated_on` timestamp NOT NULL default ''0000-00-00
00:00:00'',
PRIMARY KEY (`id`),
KEY `user_key` (`user_id`),
KEY `node_key` (`node_id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
CREATE TABLE `users` (
`id` int(11) NOT NULL auto_increment,
`created_on` timestamp NOT NULL default
CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP,
`updated_on` timestamp NOT NULL default
''0000-00-00 00:00:00'',
`nickname` varchar(255) NOT NULL default '''',
`firstname` varchar(255) NOT NULL default '''',
`lastname` varchar(255) NOT NULL default '''',
`email` varchar(255) NOT NULL default '''',
`passwd` varchar(100) NOT NULL default '''',
PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;
My question now is, is this a nice design and is this
easy to implement with rails? And how should I
implement my models in rails, should I use inheritance
or make sure that each NODE extensions sets the
correct data in the NODE table?
Regards, Luca
___________________________________________________________
Telefonate ohne weitere Kosten vom PC zum PC: http://messenger.yahoo.de
Rails (or more specifically ActiveRecord) is based on a single table per inheritance tree model. So all your Node subclasses will be persisted in the NODE table. You should also add a ''type'' column in this table so that ActiveRecord can track what is the type of persisted instances. Cheers, Matthieu Riou.>Hi everybodyI am totally new to rails and I am trying to start atinyproject to get familiar with rails. But I alreadygot my first problem and I would be happy if somebodycould point me in the best and cleanest direction.I am trying to develop a small gallery app. Since Iwould like to add more features in future I am tryingto design a clean OO architecture of my models:The base object should be NODE. All other objectsextend NODE, those are GALLERY and IMAGE (a GALLERYconsists of 0..* IMAGEs). Each NODE has an owner(user_id) plus some default fields like created_on andupdated_on. Futhermore there is an object COMMENTwhich can be attached to any object that extends NODE(belongs_to NODE).According to this design I modeled the db schema asfollows:CREATE TABLE `nodes` ( `id` int(11) NOT NULL auto_increment, `user_id` int(11) NOT NULL default ''0'', `created_on` timestamp NOT NULL defaultCURRENT_TIMESTAMP on update CURRENT_TIMESTAMP, `updated_on` timestamp NOT NULL default ''0000-00-0000:00:00'', PRIMARY KEY (`id`)) ENGINEu003dMyISAM DEFAULT CHARSETu003dlatin1;DROP TABLE IF EXISTS `galleries`;CREATE TABLE `galleries` ( `id` int(11) NOT NULL auto_increment, `node_id` int(11) NOT NULL default ''0'', `user_id` int(11) NOT NULL default ''0'', `title` varchar(255) NOT NULL default '''', `descr` text NOT NULL, PRIMARY KEY (`id`), KEY `user_key` (`user_id`), KEY `node_key` (`node_id`)) ENGINEu003dMyISAM DEFAULT CHARSETu003dlatin1;DROP TABLE IF EXISTS `images`;CREATE TABLE `images` ( `id` int(11) NOT NULL auto_increment, `user_id` int(11) NOT NULL default ''0'', `gallery_id` int(11) NOT NULL default ''0'', `node_id` int(11) NOT NULL default ''0'', `title` varchar(255) NOT NULL default '''', `descr` text NOT NULL, PRIMARY KEY (`id`), KEY `gallery_key` (`gallery_id`), KEY `node_key` (`node_id`), KEY `user_key` (`user_id`)) ENGINEu003dMyISAM DEFAULT CHARSETu003dlatin1;CREATE TABLE `comments` ( `id` int(11) NOT NULL default ''0'', `node_id` int(11) NOT NULL default ''0'', `user_id` int(11) NOT NULL default ''0'', `title` varchar(255) NOT NULL default '''', `body` text NOT NULL, `created_on` timestamp NOT NULL defaultCURRENT_TIMESTAMP on update CURRENT_TIMESTAMP, `updated_on` timestamp NOT NULL default ''0000-00-0000:00:00'', PRIMARY KEY (`id`), KEY `user_key` (`user_id`), KEY `node_key` (`node_id`)) ENGINEu003dMyISAM DEFAULT CHARSETu003dlatin1;CREATE TABLE `users` ( `id` int(11) NOT NULL auto_increment, `created_on` timestamp NOT NULL defaultCURRENT_TIMESTAMP on update CURRENT_TIMESTAMP, `updated_on` timestamp NOT NULL default''0000-00-00 00:00:00'', `nickname` varchar(255) NOT NULL default '''', `firstname` varchar(255) NOT NULL default '''', `lastname` varchar(255) NOT NULL default '''', `email` varchar(255) NOT NULL default '''', `passwd` varchar(100) NOT NULL default '''', PRIMARY KEY (`id`)) ENGINEu003dMyISAM DEFAULT CHARSETu003dlatin1;My question now is, is this a nice design and is thiseasy to implement with rails? And how should Iimplement my models in rails, should I use inheritanceor make sure that each NODE extensions sets thecorrect data in the NODE table?Regards, Luca___________________________________________________________Telefonate ohne weitere Kosten vom PC zum PC: http://messenger.yahoo.de_______________________________________________Rails mailing listRails-1W37MKcQCpIf0INCOvqR/lW5/+frIcHfeBImoM+uyKU@public.gmane.org://lists.rubyonrails.org/mailman/listinfo/rails
Luca, what is the motivation for your universal Node association? I believe it may not be neccessary. For example, the user_id column is currently included in Node as well as each of the models associated with Node. Also, fields like created_on/updated_on are pretty integral to each model, so unless you''re designing an elaborate metadata storage engine, I''d leave them right in the model they describe. You might consider dropping your Node class, and distributing its columns amongt the models as needed. For example, if a gallery owner also owns all images in the gallery, you wouldn''t need the user_id field in the images table, as it would be available by association. Keep it simple, and Rails will be your friend :) Use InnoDB not MyISAM, or else you won''t get to use transactional tests. I ran into that tree recently :) cheers Gerret On 12/23/05, Luca Marinucci <lmarinucci-/E1597aS9LQAvxtiuMwx3w@public.gmane.org> wrote:> Hi everybody > > I am totally new to rails and I am trying to start a > tiny project to get familiar with rails. But I already > got my first problem and I would be happy if somebody > could point me in the best and cleanest direction. > > I am trying to develop a small gallery app. Since I > would like to add more features in future I am trying > to design a clean OO architecture of my models: > > The base object should be NODE. All other objects > extend NODE, those are GALLERY and IMAGE (a GALLERY > consists of 0..* IMAGEs). Each NODE has an owner > (user_id) plus some default fields like created_on and > updated_on. Futhermore there is an object COMMENT > which can be attached to any object that extends NODE > (belongs_to NODE). > > According to this design I modeled the db schema as > follows: > > CREATE TABLE `nodes` ( > `id` int(11) NOT NULL auto_increment, > `user_id` int(11) NOT NULL default ''0'', > `created_on` timestamp NOT NULL default > CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP, > `updated_on` timestamp NOT NULL default ''0000-00-00 > 00:00:00'', PRIMARY KEY (`id`) > ) ENGINE=MyISAM DEFAULT CHARSET=latin1; > > DROP TABLE IF EXISTS `galleries`; > CREATE TABLE `galleries` ( > `id` int(11) NOT NULL auto_increment, > `node_id` int(11) NOT NULL default ''0'', > `user_id` int(11) NOT NULL default ''0'', > `title` varchar(255) NOT NULL default '''', > `descr` text NOT NULL, > PRIMARY KEY (`id`), > KEY `user_key` (`user_id`), > KEY `node_key` (`node_id`) > ) ENGINE=MyISAM DEFAULT CHARSET=latin1; > > DROP TABLE IF EXISTS `images`; > CREATE TABLE `images` ( > `id` int(11) NOT NULL auto_increment, > `user_id` int(11) NOT NULL default ''0'', > `gallery_id` int(11) NOT NULL default ''0'', > `node_id` int(11) NOT NULL default ''0'', > `title` varchar(255) NOT NULL default '''', > `descr` text NOT NULL, > PRIMARY KEY (`id`), > KEY `gallery_key` (`gallery_id`), > KEY `node_key` (`node_id`), > KEY `user_key` (`user_id`) > ) ENGINE=MyISAM DEFAULT CHARSET=latin1; > > CREATE TABLE `comments` ( > `id` int(11) NOT NULL default ''0'', > `node_id` int(11) NOT NULL default ''0'', > `user_id` int(11) NOT NULL default ''0'', > `title` varchar(255) NOT NULL default '''', > `body` text NOT NULL, > `created_on` timestamp NOT NULL default > CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP, > `updated_on` timestamp NOT NULL default ''0000-00-00 > 00:00:00'', > PRIMARY KEY (`id`), > KEY `user_key` (`user_id`), > KEY `node_key` (`node_id`) > ) ENGINE=MyISAM DEFAULT CHARSET=latin1; > > CREATE TABLE `users` ( > `id` int(11) NOT NULL auto_increment, > `created_on` timestamp NOT NULL default > CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP, > > `updated_on` timestamp NOT NULL default > ''0000-00-00 00:00:00'', > `nickname` varchar(255) NOT NULL default '''', > `firstname` varchar(255) NOT NULL default '''', > `lastname` varchar(255) NOT NULL default '''', > `email` varchar(255) NOT NULL default '''', > `passwd` varchar(100) NOT NULL default '''', > PRIMARY KEY (`id`) > ) ENGINE=MyISAM DEFAULT CHARSET=latin1; > > My question now is, is this a nice design and is this > easy to implement with rails? And how should I > implement my models in rails, should I use inheritance > or make sure that each NODE extensions sets the > correct data in the NODE table? > > Regards, Luca > > > > > > > ___________________________________________________________ > Telefonate ohne weitere Kosten vom PC zum PC: http://messenger.yahoo.de > _______________________________________________ > Rails mailing list > Rails-1W37MKcQCpIf0INCOvqR/iCwEArCW2h5@public.gmane.org > http://lists.rubyonrails.org/mailman/listinfo/rails >
Hi Gerret First, thx for your quick response!> what is the motivation for your universal Node > association?The motivation is to have an extendable content model, so that I can easily add new content types such as articles or documents in future. Following this approach it will be for example possible to allow to add comments to all kind of content types. But you are right, the user_id field should be removed from both tables, GALLERIES and IMAGES.> Use InnoDB not MyISAM, or else you won''t get to use > transactional tests. I ran into that tree recently:) Ah great, thx for the hint! Luca> On 12/23/05, Luca Marinucci <lmarinucci-/E1597aS9LQAvxtiuMwx3w@public.gmane.org> > wrote: > > Hi everybody > > > > I am totally new to rails and I am trying to start > a > > tiny project to get familiar with rails. But I > already > > got my first problem and I would be happy if > somebody > > could point me in the best and cleanest direction. > > > > I am trying to develop a small gallery app. Since > I > > would like to add more features in future I am > trying > > to design a clean OO architecture of my models: > > > > The base object should be NODE. All other objects > > extend NODE, those are GALLERY and IMAGE (a > GALLERY > > consists of 0..* IMAGEs). Each NODE has an owner > > (user_id) plus some default fields like created_on > and > > updated_on. Futhermore there is an object COMMENT > > which can be attached to any object that extends > NODE > > (belongs_to NODE). > > > > According to this design I modeled the db schema > as > > follows: > > > > CREATE TABLE `nodes` ( > > `id` int(11) NOT NULL auto_increment, > > `user_id` int(11) NOT NULL default ''0'', > > `created_on` timestamp NOT NULL default > > CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP, > > `updated_on` timestamp NOT NULL default > ''0000-00-00 > > 00:00:00'', PRIMARY KEY (`id`) > > ) ENGINE=MyISAM DEFAULT CHARSET=latin1; > > > > DROP TABLE IF EXISTS `galleries`; > > CREATE TABLE `galleries` ( > > `id` int(11) NOT NULL auto_increment, > > `node_id` int(11) NOT NULL default ''0'', > > `user_id` int(11) NOT NULL default ''0'', > > `title` varchar(255) NOT NULL default '''', > > `descr` text NOT NULL, > > PRIMARY KEY (`id`), > > KEY `user_key` (`user_id`), > > KEY `node_key` (`node_id`) > > ) ENGINE=MyISAM DEFAULT CHARSET=latin1; > > > > DROP TABLE IF EXISTS `images`; > > CREATE TABLE `images` ( > > `id` int(11) NOT NULL auto_increment, > > `user_id` int(11) NOT NULL default ''0'', > > `gallery_id` int(11) NOT NULL default ''0'', > > `node_id` int(11) NOT NULL default ''0'', > > `title` varchar(255) NOT NULL default '''', > > `descr` text NOT NULL, > > PRIMARY KEY (`id`), > > KEY `gallery_key` (`gallery_id`), > > KEY `node_key` (`node_id`), > > KEY `user_key` (`user_id`) > > ) ENGINE=MyISAM DEFAULT CHARSET=latin1; > > > > CREATE TABLE `comments` ( > > `id` int(11) NOT NULL default ''0'', > > `node_id` int(11) NOT NULL default ''0'', > > `user_id` int(11) NOT NULL default ''0'', > > `title` varchar(255) NOT NULL default '''', > > `body` text NOT NULL, > > `created_on` timestamp NOT NULL default > > CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP, > > `updated_on` timestamp NOT NULL default > ''0000-00-00 > > 00:00:00'', > > PRIMARY KEY (`id`), > > KEY `user_key` (`user_id`), > > KEY `node_key` (`node_id`) > > ) ENGINE=MyISAM DEFAULT CHARSET=latin1; > > > > CREATE TABLE `users` ( > > `id` int(11) NOT NULL auto_increment, > > `created_on` timestamp NOT NULL default > > CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP, > > > > `updated_on` timestamp NOT NULL default > > ''0000-00-00 00:00:00'', > > `nickname` varchar(255) NOT NULL default '''', > > `firstname` varchar(255) NOT NULL default '''', > > `lastname` varchar(255) NOT NULL default '''', > > `email` varchar(255) NOT NULL default '''', > > `passwd` varchar(100) NOT NULL default '''', > > PRIMARY KEY (`id`) > > ) ENGINE=MyISAM DEFAULT CHARSET=latin1; > > > > My question now is, is this a nice design and is > this > > easy to implement with rails? And how should I > > implement my models in rails, should I use > inheritance > > or make sure that each NODE extensions sets the > > correct data in the NODE table? > > > > Regards, Luca > > > > > > > > > > > > > > >___________________________________________________________> > Telefonate ohne weitere Kosten vom PC zum PC: > http://messenger.yahoo.de > > _______________________________________________ > > Rails mailing list > > Rails-1W37MKcQCpIf0INCOvqR/iCwEArCW2h5@public.gmane.org > > > http://lists.rubyonrails.org/mailman/listinfo/rails > > > _______________________________________________ > Rails mailing list > Rails-1W37MKcQCpIf0INCOvqR/iCwEArCW2h5@public.gmane.org > http://lists.rubyonrails.org/mailman/listinfo/rails >___________________________________________________________ Telefonate ohne weitere Kosten vom PC zum PC: http://messenger.yahoo.de
> Rails (or more specifically ActiveRecord) is based > on a single table per inheritance tree model. So > all your Node subclasses will be persisted in the > NODE table. You should also add a ''type'' column in > this table so that ActiveRecord can track what is > the type of persisted instances.Thx for the quick response. Ok, this is a very efficient method but it gets very complex if I will add new types in future because I need to also add the new coloumns to the NODE table. Perhaps the easier and better way is to use aggregation instead of inheritance with the model classes: class Gallery < ActiveRecord::Base has_many :images belongs_to :node end Can you confirm that? Cheers, Luca> >Hi everybodyI am totally new to rails and I am > trying to start atiny > project to get familiar with rails. But I alreadygot > my first problem > and I would be happy if somebodycould point me in > the best and > cleanest direction.I am trying to develop a small > gallery app. Since > Iwould like to add more features in future I am > tryingto design a > clean OO architecture of my models:The base object > should be NODE. All > other objectsextend NODE, those are GALLERY and > IMAGE (a > GALLERYconsists of 0..* IMAGEs). Each NODE has an > owner(user_id) plus > some default fields like created_on andupdated_on. > Futhermore there is > an object COMMENTwhich can be attached to any object > that extends > NODE(belongs_to NODE).According to this design I > modeled the db schema > asfollows:CREATE TABLE `nodes` ( `id` int(11) NOT > NULL > auto_increment, `user_id` int(11) NOT NULL default > ''0'', `created_on` > timestamp NOT NULL defaultCURRENT_TIMESTAMP on > update > CURRENT_TIMESTAMP, `updated_on` timestamp NOT NULL > default > ''0000-00-0000:00:00'', PRIMARY KEY > (`id`)) > ENGINEu003dMyISAM DEFAULT CHARSETu003dlatin1;DROP > TABLE IF EXISTS > `galleries`;CREATE TABLE `galleries` ( `id` int(11) > NOT NULL > auto_increment, `node_id` int(11) NOT NULL default > ''0'', `user_id` > int(11) NOT NULL default ''0'', `title` varchar(255) > NOT NULL default > '''', `descr` text NOT NULL, PRIMARY KEY (`id`), > KEY `user_key` > (`user_id`), KEY `node_key` (`node_id`)) > ENGINEu003dMyISAM DEFAULT > CHARSETu003dlatin1;DROP TABLE IF EXISTS > `images`;CREATE TABLE `images` > ( `id` int(11) NOT NULL auto_increment, `user_id` > int(11) NOT NULL > default ''0'', `gallery_id` int(11) NOT NULL default > ''0'', `node_id` > int(11) NOT NULL default ''0'', `title` varchar(255) > NOT NULL default > '''', `descr` text NOT NULL, PRIMARY KEY (`id`), > KEY `gallery_key` > (`gallery_id`), KEY `node_key` (`node_id`), KEY > `user_key` > (`user_id`)) ENGINEu003dMyISAM DEFAULT > CHARSETu003dlatin1;CREATE TABLE > `comments` ( `id` int(11) NOT NULL default ''0'', > `node_id` int(11) > NOT NULL default ''0'', `user_id` int(11) NOT NULL > default ''0'', > `title` varchar(255) NOT NULL default '''', `body` > text NOT NULL, > `created_on` timestamp NOT NULL > defaultCURRENT_TIMESTAMP on update > CURRENT_TIMESTAMP, `updated_on` timestamp NOT NULL > default > ''0000-00-0000:00:00'', PRIMARY KEY (`id`), KEY > `user_key` > (`user_id`), KEY `node_key` (`node_id`)) > ENGINEu003dMyISAM DEFAULT > CHARSETu003dlatin1;CREATE TABLE `users` ( `id` > int(11) NOT NULL > auto_increment, `created_on` timestamp NOT NULL > defaultCURRENT_TIMESTAMP on update > CURRENT_TIMESTAMP, > `updated_on` timestamp NOT NULL default''0000-00-00 > 00:00:00'', > `nickname` varchar(255) NOT NULL default '''', > `firstname` varchar(255) > NOT NULL default '''', `lastname` varchar(255) NOT > NULL default '''', > `email` varchar(255) NOT NULL default '''', `passwd` > varchar(100) NOT > NULL default '''', PRIMARY KEY (`id`)) > ENGINEu003dMyISAM DEFAULT > CHARSETu003dlatin1;My question now is, is this a > nice design and is > thiseasy to implement with rails? And how should > Iimplement my models > in rails, should I use inheritanceor make sure that > each NODE > extensions sets thecorrect data in the NODE > table?Regards, >Luca___________________________________________________________Telefonate> ohne weitere Kosten vom PC zum PC: >http://messenger.yahoo.de_______________________________________________Rails> mailing >listRails-1W37MKcQCpIf0INCOvqR/lW5/+frIcHfeBImoM+uyKU@public.gmane.org://lists.rubyonrails.org/mailman/listinfo/rails> _______________________________________________ > Rails mailing list > Rails-1W37MKcQCpIf0INCOvqR/iCwEArCW2h5@public.gmane.org > http://lists.rubyonrails.org/mailman/listinfo/rails >___________________________________________________________ Telefonate ohne weitere Kosten vom PC zum PC: http://messenger.yahoo.de