similar to: Single Table Inheritance with self-referential join

Displaying 20 results from an estimated 500 matches similar to: "Single Table Inheritance with self-referential join"

2006 Jul 18
2
newbie help re: loading data and relationships in migrations
Hi folks, I''m new to Ruby & Rails, and have been reading the Agile Web dev & Pickaxe books with much joy! However, I need some guidance re: using migrations to load in data for tables that have relationships. For example, I have one products table and one product_photos table (defined in separate migration files). The second table has a foreign key associated with the
2008 Sep 26
0
self-referential tags, has_many_polymorphs
Hi, I''m looking to add tagging to an application, and I would like to allow self-referential tags, so that I can tag my tags. With the goal of generating a flexible tag hierarchy. After some googling it looks like acts_as_taggable is not the best piece of code, and I''m hoping to use the has_many_polymorphs plugin from http://github.com/fauna/has_many_polymorphs/tree/master.
2012 Oct 22
0
[LLVMdev] Self-referential instruction from jump threading
Hi Hal, > After investigating PR14133, I've discovered that jump threading can output self-referential instructions: > %inc.us = add nsw i32 %inc.us, 1 such instructions are valid in unreachable basic blocks. > At least in the test case for that bug report, the relevant code is later deleted (perhaps it is unreachable), and so this does not cause a problem. Unfortunately, when
2012 Oct 22
0
[LLVMdev] Self-referential instruction from jump threading
Hal Finkel wrote: > Hello, > > After investigating PR14133, I've discovered that jump threading can output self-referential instructions: > %inc.us = add nsw i32 %inc.us, 1 > > At least in the test case for that bug report, the relevant code is later deleted (perhaps it is unreachable), and so this does not cause a problem. Unfortunately, when vectorization is enabled, this
2006 May 29
2
foreign keys and referential integrity
Sans rails my normal approach to handling this would be to enforce it in the database and when a database operation failed I''d try to validate the model to produce an error message. It''s always served me pretty well. Rails expects you to validate before commiting but of course this does nothing to guarantee referential integrity. It''s perfectly possible for one
2006 Nov 29
4
how do I model self-referential entities?
Hi all - I am having some trouble figuring out how to model self-referential entities in Rails. I have a "group" model, which can have 0 or more "group" objects or 0 or more "user" objects. I tried creating a subgroup table that has a parent_group_id and a child_group_id as foreign keys but can''t figure out how to create the mapping in my ruby model
2007 Jul 26
1
Bi-directional self-referential HABTM
Hi, I''m having a little trouble figuring out how to make a self- referential HABTM bi-directional. I have a Employee class. Each employee can have a couple of bosses, who are also employees. The employee class has the following HABTM: has_and_belongs_to_many :bosses, :class_name => "Employee", :join_table => "bosses_courses", :association_foreign_key =>
2006 Jul 20
1
self referential xml using builder
Hi listers, I''m trying to build an xml doc using Builder, but I''m having trouble getting it to draw a tree structure from a self-referential table. Here''s what I''m after: ========================== ---- object structure ---- node (name => root) - node (name => child 1) - node (name => child 2) - node (name => child 2.1) - node
2006 May 02
0
Self-referential MtoM implementation
ok, guys i have followed the self referential recipe from the book it works perfect but now i have some doubts, at the end the model are modified to force the user beign added as a friend that add too who are adding him so how i can make that the full relationship doesn?t be complete until the friend beign added approves it(talking in the implementation of the code of course)? by the way,
2006 Apr 17
0
Pros/cons of doubling up in Self-Referential has_many via :through
Relative newbie so would welcome comments re structure of a self-referential relationship I''ve got. It''s started off similar to the Person HABTM friends in the Rails recipes books (working fine), but I needed to turn the join table into a full-blown model as I wanted to add attributes to it. Few tricky bits dealing with the new :through structure and understanding how :scope
2008 Jan 23
1
Self-referential HABTM SQL mal-formed when updating record
Guys, Anyone ever had this kind of problem with ActiveScaffold? Cheers, Sazima ------------------------------------------------------------------------------------------------ What steps will reproduce the problem? 1. Create self-referential HABTM application (like the common "user has friends" example) 2. Try to add more than 1 friend to a given user using ActiveScaffold. What is
2012 Jul 06
2
[LLVMdev] Self-referential function pointer
Hey guys, I could use some advice on a special case of a function pointer as a formal argument. I would like the function pointer type to contain the actual signature of the function, i.e. not a pointer to var args function. This becomes an issue when I have a function which can take a pointer to itself as an argument... our terminology for this is "a recursive procedure". That is, of
2006 Feb 25
0
self referential habtm using join tables
All: I have been working on making a self-referential habtm relationship that uses a join model because I want to store info about the relationship. I have been using two sections from Chad Fowler''s "Rails Recipes" as a guide, "Self-referential Many-to-Many Relationships" and "Many to Many Relationships Where the Relationship Itself has Data". So far I have
2012 Apr 20
1
Interactive stereoscopic 3d rendering with RGL plot3d?
Dear R Users, i' wondering, if there is any possibility to render interactive stereoscopic 3d plots in R and use the functionality of those new 3d displays (e.g. with poarisation technology) like this one: > http://shop.fujitsu.com/de/displays/display-p23t-6p-fpr-3d Does anyone know if there are developments toward this feature? Or perhaps someone know how to implement such a
2006 Feb 27
0
self-referential many-to-many using a join model
Hello! I have been working on making a self-referential habtm relationship that uses a join model because I want to store info about the relationship. I have been using two sections from Chad Fowler''s "Rails Recipes" as a guide, "Self-referential Many-to-Many Relationships" and "Many to Many Relationships Where the Relationship Itself has Data". So far I
2006 Mar 25
0
Self-Referential Many-To-Many relationships where the relationship itself has data.
Trying to model a bunch of users that have friends that are other users. clearly a job for has_and_belongs_to_many, but the trick is, they have ratings for their friends. I have gone through the Rails Recipes book, and it seems like I''m trying to combine the self-referential many-to-many recipe (12) and the many to many relationships where the relationship itself has data recipe (16). So
2012 Oct 22
4
[LLVMdev] Self-referential instruction from jump threading
Hello, After investigating PR14133, I've discovered that jump threading can output self-referential instructions: %inc.us = add nsw i32 %inc.us, 1 At least in the test case for that bug report, the relevant code is later deleted (perhaps it is unreachable), and so this does not cause a problem. Unfortunately, when vectorization is enabled, this instruction causes BBVectorize to hang. Should
2007 Oct 22
1
self-referential habtm: why are my keys null?
I''m trying to set up a directional self-referential HABTM to represent an arbitrary semi-hierarchical structure; it works for any data prepopulated into the db, but when I try to create a new relationship, I just get NULLs in both key columns (or 0''s if I turn on the no-null constraint). Here are the migrations: class CreateNodes < ActiveRecord::Migration def self.up
2006 Aug 02
2
Self-Referential has_many :through
Hello all. I am trying to create a self-referential has_many :through. I used the following site as a guide http://blog.hasmanythrough.com/articles/2006/04/21/self-referential-through but it still doesn''t appear to be working. I have two models. Person and Relationship. A person has many contacts (Which is another person) through relationships class Person < ActiveRecord::Base
2006 Aug 15
2
How to access attribute in a self-referential many-to-many relationship
Hello List, I created a self-referential many-to-many relationship (as described in the book Rails recipe #18), where I have a model that has many-to-many relationships with itself. In this case, it''s person who can become friends. The join table looks like this: mysql> select * from friends_people; +-----------+-----------+-----------+ | person_id | friend_id | confirmed |