Displaying 20 results from an estimated 1000 matches similar to: "Breakdowns in has_many abstraction"
2009 Feb 27
4
Optimize for loop / find last record for each person
I want to find the last record for each person_id in a data frame
(from a SQL database) ordered by date. Is there a better way than
this for loop?
for (i in 2:length(history[,1])) {
if (history[i, "person_id"] == history[i - 1, "person_id"])
history[i, "order"] = history[i - 1, "order"] + 1 # same person
else
history[i,
2006 Mar 13
3
HABTM: two habtm''s between the same two tables
Imagine I want to track people, and the clubs that they belong to.
table people with columns person_id, person_name
table clubs with columns club_id, club_name
And I have the association table:
table clubs_people with columns person_id, club_id
Now I know how to do this habtm between the two, in order to associate
people with clubs that they belong to.
However my application also needs a
2006 Oct 02
2
when to use find_by_sql
I have a bunch of queries to compute some counters, like
find_by_sql(<<-SQL
SELECT p.*, c.nfavourites
FROM people p, (
SELECT fp.person_id, COUNT(fp.user_id) as nfavourites
FROM favourite_people fp, users u
WHERE fp.user_id = u.id
AND u.cluster = ''#{in_cluster_of_user.cluster}''
GROUP BY fp.person_id
) as c
WHERE
2006 May 16
1
:conditions on has_one realationship
Hi there,
I''m currently building a membership application and I want to be able
to select, not just all the memberships, but the most current
membership from the database on a per user basis. I have linked the
tables as shown:-
class Membership < ActiveRecord::Base
belongs_to :payment
belongs_to :person
end
class Person < ActiveRecord::Base
has_many :memberships
2006 Jul 13
2
having a problem with acts_as_state_machine
Hi all:
Below is s a dump from script/console in development env.
Am I not supposed to be able to find the record later and use the
state machine functionality, or have I missed something? Thanks
Forrest
----------------------------
>> ts2 = TalkSession.create( :person_id => 2, :pattern_id => 2)
=> #<TalkSession:0x35811f0 @attributes={"pattern_id"=>2,
2006 Jan 09
3
Design Question
I am sure some of you can give me an insight into this. This is more
towards the database design for the scenario below:
Say for example,
I have a person table and this person can have different address types.
One could be Home and the other could be say Office.
Should be model this
Table people
id
fname
lname
Table addresses
id
person_id
addr1
addr2
....
or
Table people
id
fname
lname
2008 May 02
1
names of select elements inside a fields_for block not generated as expected
Hey All,
I''m trying to play along w/the ''complex forms 1'' railscast
(http://railscasts.com/episodes/73) and having trouble. The view is
projects/new. I''m trying to add some project_people to the form w/code
like so:
<% form_for(@project) do |f| %>
[project stuff here]
<% for pp in @project.project_person %>
<% fields_for
2006 Jun 06
1
Please Help with single table inheritance relationships
I''ve been searching the web, wikis, and more, and I haven''t turned up
examples of how to have multiple entities in a single-table inheritance
related to anything.
I have an addresses table, but multiple entities can have Addresses:
both Person (which has 2 addresses) and Retailer. I''ve been told that I
need to use single-table inheritance, and this was my attempt:
2007 Feb 26
4
update_attributes and validations
I have a Person model. Person has_many lab_urls. The LabUrl model has
a title and a url, which are both required.
Now, I want to update a LabUrl object and stick some invalid data in
there. And I want the person that has that invalid LabUrl to now be
invalid, too. That doesn''t seem like too much to ask for. How can I do
that?
Right now, this is happening:
>> me = Person.find(1)
2006 Mar 09
4
sort-weirdness - active record issue?
I''m selecting data into a controller and sorting it. The code (in the
controller) looks like this:
def index
@assignments = []
tasks = Task.find(:all, :conditions => ["person_id = ? and
actual_end_date is null", session[:user].id.to_s ])
issues = Issue.find(:all, :conditions => ["person_id = ? and status
<>
2010 Nov 02
7
Testing attr_accessible (and/or attr_protected)
I''ve been puzzling over how to test that attr_accessible has been set
for the correct columns; but the tests I''ve come up with so far seem
to fail to fail when I expect. I came across this old message from
this list:
http://www.mail-archive.com/rspec-users at rubyforge.org/msg01570.html
Which seemed like a plausible example, but my attempt (modeled on the
example)
2013 Nov 19
1
Does function read.sas7bdat() have some memory limitations?
Dear R-ers,
I was trying to read in a large sas7bdat file (size 148094976 bytes) using 'read.sas7bdat()', but it did not read in the data correctly. E.g., the first 5 rows will come out like this (I'm omitting other columns to keep it readable):
PERSON_ID age
1 5.399114e-315 5.329436e-315
2 5.399114e-315 5.328302e-315
3 5.399114e-315 5.332026e-315
4
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
2007 Mar 19
1
HOWTO: Multiple file upload with file_column
Lots of requests but not many answers on this topic. Here is how you do
it:
FORM:
<table>
<% for i in 1..6 %>
<tr>
<td class=''Label''><label>Title</label></td>
<td><input id="<%= "picture_#{i}_title" %>" name="<%=
"picture[#{i}][title]" %>" size="30"
2006 Aug 02
2
many-to-one relationship, do I need a second table?
Ok, to keep things short. Im wondering if I need a secondary
relationship table to handle my many-to-one relationships. Here is an
example of what I''ve written down. For instance say I want to find all
of the people in a given location.
class Location < AR:Base
has_many :people
end
class Person < AR:Base
belongs_to :location
end
My SQL tables look like:
CREATE TABLE
2006 May 28
3
Association of table to itself
I''m curious what would be the best way to represent people and whether the
person has someone marked as their friend. Here are my thoughts so far:
People table
- id
- name
Relationships table
- person_id
- friend_id
Now my problem is I don''t know how to set up these associations (if this is
even correct). Friend_id would be an id to someone else from the people
table.
2006 Apr 03
1
Single table inheritance and relations
All,
I''ve a question concerning STI in Rails. Let''s say I''ve a Person class
and two classes that inherit from Person: User and Customer. In the DB
I''ve the people table to store both instances of User and Customer.
Now, let''s say I also have Address class, which references a Customer,
and each customer has many addresses. How should I name the
2006 Mar 17
4
deleting from hash question
I''m a ruby newbie and have what is probably a relatively simple problem
I''m trying to solve. Say that I created a hash:
TASKS = {
"homework" => "Do Your Homework",
"chores" => "Your Have Chores",
"exercise" => "Don''t Forget to Exercise"
}
and then I had an Assignment model with:
def
2007 Nov 22
1
has_many :through questions
I''ve created the following associations using :through:
class Person < ActiveRecord::Base
has_many :attendees, :dependent => :destroy
has_many :events, :through => :attendees, :uniq => true
end
class Event < ActiveRecord::Base
has_many :attendees, :dependent => :destroy
has_many :people, :through => :attendees, :uniq => true
2004 Nov 20
1
how to suppress whiskers in a bwplot?
dear R-help,
i have looked carefully through the R-help archives for information on how
to suppress whiskers in a bwplot. someone asked this question a while
ago, but the answer he received is not available in the archives.
but i did manage to get my hands on a panel function (called
"my.panel") that is supposed to do this (the function is reproduced at the
end of the email, below).