Is it possible to use an attribute of a child to group a query? Post.find(:all, :include => [ :authors, :comments ], :group=>'authors.city') does not work. However, I am able to use author.city as part of the conditions. ...
Background Normal rails eager-loading of collections works like this: Person.find(:all, :include=>:companies) This generates some sql which does LEFT OUTER JOIN companies ON people.company_id = companies.id Question However, I need a custom join (this could also arise if I was using find_by_sql) so I can't use the vanilla :includ...
I'd like the canonical way to do this. My Google searches have come up short. I have one ActiveRecord model that should map to a different database than the rest of the application. I would like to store the new configurations in the database.yml file as well. I understand that establish_connection should be called, but it's not clea...
I'm creating an ORM in PHP, and I've got a class 'ORM' which basically creates an object corresponding to a database table (I'm aiming for similar to/same functionality as an ActiveRecord pattern.) ORM itself extends 'Database', which sets up the database connection. So, I can call: $c = new Customer(); $c->name = 'John Smith'; $c->sav...
I have this problem, I'm using Castle ActiveRecord and when I update I verify changes in the object in the OnFlushDirty event. However, when I access to the previouState["MyProperty"], it turns to be null and I can't get the old value. Do you know why? this is the code; protected override bool OnFlushDirty(object id, System.Colle...
Hi all, I'm getting some objects from an external library and I need to store those objects in a database. Is there a way to create the tables and relationships starting from the objects, or I have to dig into them and create migrations and models by hand? Thanks! Roberto ...
How do I get a list of all the tables defined for the database when using active record? ...
I'm working on a project for my school on rails (don't worry this is not graded on code) and I'm looking for a clean way to traverse relationships in ActiveRecord. I have ActiveRecord classes called Users, Groups and Assignments. Users and Groups have a HABTM relationship as well as Groups and Assignments. Now what I need is a User func...
I've been developing web applications for a while and i am quite comfortable with mySql, in fact as many do i use some form of SQL almost every day. I like the syntax and a have zero problems writing queries or optimizing my tables. I have enjoyed this mysql api. The thing that has been bugging me is Ruby on Rails uses ActiveRecord an...
I use serialize in one ActiveRecord model to serialize an Array of simple Hashes into a text database field. I even use the second parameter to coerce deserialization into Arrays. class Shop < ActiveRecord::Base serialize : recipients, Array end It seems to work fine but, after a few requests, the content of recipients turns to Hash...
I get a mysql error: #update (ActiveRecord::StatementInvalid) "Mysql::Error: #HY000Got error 139 from storage engine: When trying to update a text field on a record with a string of length 1429 characters, any ideas on how to track down the problem? Below is the stacktrace. from /var/www/releases/20081002155111/vendor/rails/activere...
I'm trying to create a named_scope that uses a join, but although the generated SQL looks right, the result are garbage. For example: class Clip < ActiveRecord::Base named_scope :visible, { :joins => "INNER JOIN series ON series.id = clips.owner_id INNER JOIN shows on shows.id = series.show_id", :conditions=>"shows.visi...
I have an application in which attr_accessor is being used to keep temporary data for a model which will be passed to a rake task. Seeing there is not a database field for these attributes and they are not being calculated from database data, will the attr_accessor data persist and be available to the rake task? What happens if I need ...
I am in the start up of a project using ASP.NET MVC and have started creating my models. Since I know some Ruby On Rails and would like to use a system as similar to Rails Active Record as possible. Have anyone used Castle Projects Active Record in a ASP.NET MVC application (or any application that is relevant) and have some experience ...
In our program, each customer gets their own database. We e-mail them a link that connects them to their database. The link contains a GUID that lets the program know which database to connect to. How do I dynamically and programatically connect ActiveRecord to the right db? ...
have you re-factored from an Active Record to a Data Mapper pattern? what conditions prompted the switch? i'm primarily interested in web based applications, but would like to know the challenges that accompany such a move in any environment. ...
Let's say I'm writing a Library application for a publishing company who already has a People application. So in my Library application I have class Person < ActiveResource::Base self.site = "http://api.people.mypublisher.com/" end and now I want to store Articles for each Person: class Article < ActiveRecord::Base belongs_to :...
This is an age-old question where given a table with attributes 'type', 'variety' and 'price', that you fetch the record with the minimum price for each type there is. In SQL, we can do this by: select f.type, f.variety, f.price from ( select type, min(price) as minprice from table group by type ) as x inner join table as f on f....
I have named_scope which is reused in multiple ActiveRecord models. For example: named_scope :limit, lambda {|limit| {:limit => limit}} What is the best practice to extract this code to be shared across models. Is it possible to extract it to a module or should I rather reopen ActiveRecord::Base class? ...
I'm building an app in Ruby on Rails, and I'm including 3 of my models (and their migration scripts) to show what I'm trying to do, and what isn't working. Here's the rundown: I have users in my application that belong to teams, and each team can have multiple coaches. I want to be able to pull a list of the coaches that are applicable...