Displaying 20 results from an estimated 10000 matches similar to: "eager associations and limit/offset"
2005 Aug 04
1
Pagination and :include (eager associations)
I have tried to use eager association with pagination, but
the :include option is not supported:
Here''s the one-line pagination call without :include
@link_pages, @links = paginate :link, :per_page => 10, :order_by
=> sort_clause
and here the work around, using the "classic" method
# @link_pages = Paginator.new self, Link.count, 10,
2006 Jun 28
4
Load IDs For Limited Eager Loading
Hi
Trying to cut down on queries with eager loading and noticed the
following in development.log
Load IDs For Limited Eager Loading - SELECT id ....etc
Followed by
Load Including Associations - SELECT table.id ... etc
Is this common practice? What is limted eager loading?
Cheers
Mark
--
Posted via http://www.ruby-forum.com/.
2006 Aug 04
2
problem eager loading with sti
Here''s the setup (working off Rails 1.1.4):
Class Project
belongs_to :employee
Class Employee < Person
has_many :projects
When I try to paginate(:employees, :include =>
:projects) I get the error "Association named
''projects'' was not found; perhaps you misspelled it?"
I can :include other models that the Person class
has_many or habtm of, and if I
2008 Jan 04
1
eager loading and polymorphic associations
There is a dedicated section about eager loading in the docs. A
coworker discovered eager loading does not work in polymorphic
associations the hard way :-) so I''ve written a patch that documents it:
http://dev.rubyonrails.org/ticket/10610
There are at least a couple of tickets that implement something that
would change that though:
http://dev.rubyonrails.org/ticket/9640
2008 Apr 21
2
Eager Loading Polymorphic Associations
Hi,
I''m searching for a method of eager loading polymorphic associations under
activerecord 2.0.2. After some initial google-fu I came up with a link to
an enhancement that''s been added to edge:
http://dev.rubyonrails.org/ticket/8119
Anyone have any idea how long that might take to work its way into a general
release? I''m early in development now so I can afford to
2006 Mar 31
2
Eager loading of polymorphic associations
Polymorphic associations work great until I try to do some eager
loading through :include. In my example, the interface name is
":imagehaver". Here''s my little eagerly loading find line:
Image.find(params[:id], :include => :imagehaver)
All it gives me is an ActiveRecord::EagerLoadPolymorphicError with no
further explanation. I haven''t been able to dig up anything
2006 Jan 31
4
Rails bug? Conditions on associations ignored by eager loading
I''m looking for someone to confirm the following as a bug in Rails
1.0 before I post it to Trac.
If I use eager loading on an association that has conditions defined,
the conditions are ignored.
The following example illustrates the problem. I have two tables:
create_table "blogs", :force => true do |t|
t.column "name", :string
end
create_table
2008 Apr 23
2
Bug in eager loading and polymorphic associations?
Hi friends, i''m usgin the edge version because i need eager loading on
polymorphic associations support, but i see this:
Message.find(:first, :include => :owner) #This generate this query:
SQL (0.000072) SET SQL_AUTO_IS_NULL=0
Message Load (0.000389) SELECT * FROM `messages`
User Load (0.001070) SELECT * FROM `users` WHERE (users.id IN
(1,2))
And this Message.find(:first,
2006 Sep 03
1
New Technique: Subsets of has_many Associations
I just now thought of this, and sure enough it works like a charm (at
least so far in my limited testing):
has_many :events, :dependent => :delete_all
has_many :upcoming_events, :class_name => "Event", :conditions =>
"date > NOW()"
The purpose of this is that it makes eager loading of subsets of
associations possible without replacing all the magic of the
2005 Jun 13
1
Question on Eager Associations
Hi - I am trying to use eager associations to cut down on database queries.
I have a feeds table, an items table, a categories table, and a
categories_items table.
feeds have items, and items have many categories (and categories can
be assigned to many items), thus the categories_items table which is a
many-many join table.
I do
@feed = Feed.find(1)
which works fine, but now I want to use
2005 Dec 14
0
eager loading all associations
Hi Railers,
Is there a way to specify all relations in a :include option while
find()ing?
I have a model with a lot of associations, and sometimes i would like to
query for all them.
Something like Model.find(params[:id], :include => :all) would be nice.
Alternatively, i don''t know if there is a mehod to retrieve all model''s
associations, to do something like
2008 Sep 03
5
Eager load associations in Oracle problem with more than 1000 records
I think Rails 2.1 introduced a bug when eager loading of associations
with Oracle. In 2.1 ActiveRecord loads the included table with a big
''IN'' query: ''where association.id in (1, 2, 3, 4...)''. The problem
is that Oracle has a hard limit of 1000 values in an IN clause. I get
this error:
''OCIError: ORA-01795: maximum number of expressions in a list
2006 Apr 24
9
Confusion with expressing many to many relationship
Hi folks, I am in the process of converting an existing non-rails
application to rails, and am not sure what the best approach would be
for specifying the relationship between the two sets of data.
I''ll describe the existing table structures first.
Table 1: Urls
Each url has a unique id and two lists of Phrases, these are currently
setup as varchars with "," delimitation -
2012 Sep 08
3
Polymorphic has_and_belongs_to_many association
Hi,
I''m currently having the situation where I have to implement a polymorphic
has_and_belongs_to_many by introducing an in between model that handles all
the "has_many :as" and "belongs_to :polymorphic" association
implementations... and is not doing anything else. Thing I don''t like it
here is, I am unnecessarily loading AR instances only to execute SQL
2010 Aug 05
3
how to ? Rails 3 ActiveRecord eager loading and AREL
Hello everyone,
I would like to eager load scoped records to avoid queries executed in a
loop (huge performance impact).
The "scoped" part is what is giving me a hard time.
I''m using Rails3 RC.
Does anyone have any idea how I can do it?
Here is a test case : we have an "Article" and a "Comment" Activerecord
models,
article has many comments
comment
2009 Oct 08
6
Eager Loading a Relationship That Has No PK/FK
I''m attempting to wrestle an old DB into Rails.
This relationship is giving me trouble:
class Show < AR::Base
has_many :segments
end
class Segment < AR::Base
belongs_to :show
has_one :media #this has no PK/FK relation
end
A Segment is "linked" to Media by Media.name, which is the result of
concatenating Segment.name and Segment.part. As I said there are is no
2006 Jul 31
0
Patch for #3438: Eager loading doesn''t respect :order of associations
Hello all,
I still have a patch for #3438 (eager loading doesn''t respect
association orders); it passes all unit tests, and has additional unit
tests with full coverage. The patch is attached.
== The Bug ==
Author.find(1).posts != Author.find(1, :include => [:posts]).posts
if Author has_many :posts, :order => anything.
This means that either one must avoid eager loading or
2005 May 01
0
Eager loading with self associations
Hi,
I''m new to ruby on rails and I''m trying to make a self association (as
when an employee has a manager, whom is also an employee) work with
eager loading on postgres, but the generated sql is wrong
the two ends of the association are in the same table (setores), the
foreign key is setor_pai and the generated SQL contains this:
FROM setores LEFT OUTER JOIN setores ON
2006 Jul 03
0
Eager loading of ''is meant to be nil'' Associations
If I ''find'' using :include, and some included associations are null,
then looping through the array executing ''if obj[i].assoc'' accesses the
database for a second time (as obj.assoc is nil).
eg
Topic, has_many posts
Post has_one email
and
posts = Post.find(:all, :condition => ''posts.topic_id = 10'', :include =>
2006 Apr 30
2
HABTM: Find sorted by number of associations
Hi,
I''ve been googling and searching the forums for some time
but can''t seem to find exactly what I''m looking for.
Suppose User HABTM Products (for example a favorites list). I would like to
construct a single query for finding Products ordered by the number of
Users that have flagged them as favorites.
Although I can construct the query using SQL a with a