Hi All, I see that named scopes can be used to inject additional AND conditions into the WHERE component of a query, however is there any way to inject an OR condition? Say for example I have a Company and Office model, the Company has_many Offices and both the Company and Office own many child models. The Office should be able to see the child models that he specifically owns, but also those owned by his parent company that have been designated to be shared throughout the company. So what I really want to do is something like: @items = current_office.items.including_shared where the including_shared scope would have to inject a condition like ''OR (company_id = x AND shared = 1)'' into the query. However I can''t see a way to do this. I can get the results I want from either: @items = current_office.items @items << current_company.items.shared or using a single scope on the Item class: Item.for_current_office_and_shared However I don''t like that the first one requires two db calls, and for the second one I prefer to start all fetches with either current_company/office so that I can easily tell that they are properly scoped to the current application instance. Anyway I''m probably being a bit anal, but just wondered if anyone has any ideas. Many thanks! -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
2010/1/21 Ginty <stephen.f.mcginty-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>:> Hi All, > > I see that named scopes can be used to inject additional AND > conditions into the WHERE component of a query, however is there any > way to inject an OR condition? > > Say for example I have a Company and Office model, the Company > has_many Offices and both the Company and Office own many child > models. > > The Office should be able to see the child models that he specifically > owns, but also those owned by his parent company that have been > designated to be shared throughout the company. > > So what I really want to do is something like: > > @items = current_office.items.including_shared > > where the including_shared scope would have to inject a condition like > ''OR (company_id = x AND shared = 1)'' into the query. > However I can''t see a way to do this.Just put the OR in the :conditions parameter of the named scope just as you would for a normal find with OR conditions. Colin> > I can get the results I want from either: > > @items = current_office.items > @items << current_company.items.shared > > or using a single scope on the Item class: > > Item.for_current_office_and_shared > > However I don''t like that the first one requires two db calls, and for > the second one I prefer to start all fetches with either > current_company/office so that I can easily tell that they are > properly scoped to the current application instance. > > Anyway I''m probably being a bit anal, but just wondered if anyone has > any ideas. > > Many thanks! > > -- > You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. > To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en. > > > >-- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
Thanks for the reply, however I don''t think that will work. I already have the current_office in the scope and so it will generate something like: SELECT * WHERE (office_id = x) *AND* (company_id = x AND shared = 1) By specifying the :conditions in the named scope I can stick any OR I want in the second half of the conditions, however it is the *AND* in the middle that is still the problem and I want to turn it into an OR. On Jan 21, 7:36 am, Colin Law <clan...-gM/Ye1E23mwN+BqQ9rBEUg@public.gmane.org> wrote:> 2010/1/21 Ginty <stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>: > > > > > Hi All, > > > I see that named scopes can be used to inject additional AND > > conditions into the WHERE component of a query, however is there any > > way to inject an OR condition? > > > Say for example I have a Company and Office model, the Company > > has_many Offices and both the Company and Office own many child > > models. > > > The Office should be able to see the child models that he specifically > > owns, but also those owned by his parent company that have been > > designated to be shared throughout the company. > > > So what I really want to do is something like: > > > @items = current_office.items.including_shared > > > where the including_shared scope would have to inject a condition like > > ''OR (company_id = x AND shared = 1)'' into the query. > > However I can''t see a way to do this. > > Just put the OR in the :conditions parameter of the named scope just > as you would for a normal find with OR conditions. > > Colin > > > > > I can get the results I want from either: > > > @items = current_office.items > > @items << current_company.items.shared > > > or using a single scope on the Item class: > > > Item.for_current_office_and_shared > > > However I don''t like that the first one requires two db calls, and for > > the second one I prefer to start all fetches with either > > current_company/office so that I can easily tell that they are > > properly scoped to the current application instance. > > > Anyway I''m probably being a bit anal, but just wondered if anyone has > > any ideas. > > > Many thanks! > > > -- > > You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. > > To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > > To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > > For more options, visit this group athttp://groups.google.com/group/rubyonrails-talk?hl=en.-- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
2010/1/21 Ginty <stephen.f.mcginty-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>:> Thanks for the reply, however I don''t think that will work. > > I already have the current_office in the scope and so it will generate > something like: > > SELECT * WHERE (office_id = x) *AND* (company_id = x AND shared = 1) > > By specifying the :conditions in the named scope I can stick any OR I > want in the second half of the conditions, however it is the *AND* in > the middle that is still the problem and I want to turn it into an OR.I think I understand now, you mean you want to chain named scopes such that the second one *adds* additional items into the first one. So if you have @items = scope_1 then @items = scope_1.scope_2 will have more items than the first statement. I don''t think that is possible, when chaining scopes I believe that the results of one is effectively passed to the next so it can only filter some out, not add more. I may be wrong though. You could do it by providing a method of Office called, for example items_including_shared that runs the two queries and combines them, then you can say @items = current_office.items_including_shared which is pretty close to what you wanted. Colin> > > On Jan 21, 7:36 am, Colin Law <clan...-gM/Ye1E23mwN+BqQ9rBEUg@public.gmane.org> wrote: >> 2010/1/21 Ginty <stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>: >> >> >> >> > Hi All, >> >> > I see that named scopes can be used to inject additional AND >> > conditions into the WHERE component of a query, however is there any >> > way to inject an OR condition? >> >> > Say for example I have a Company and Office model, the Company >> > has_many Offices and both the Company and Office own many child >> > models. >> >> > The Office should be able to see the child models that he specifically >> > owns, but also those owned by his parent company that have been >> > designated to be shared throughout the company. >> >> > So what I really want to do is something like: >> >> > @items = current_office.items.including_shared >> >> > where the including_shared scope would have to inject a condition like >> > ''OR (company_id = x AND shared = 1)'' into the query. >> > However I can''t see a way to do this. >> >> Just put the OR in the :conditions parameter of the named scope just >> as you would for a normal find with OR conditions. >> >> Colin >> >> >> >> > I can get the results I want from either: >> >> > @items = current_office.items >> > @items << current_company.items.shared >> >> > or using a single scope on the Item class: >> >> > Item.for_current_office_and_shared >> >> > However I don''t like that the first one requires two db calls, and for >> > the second one I prefer to start all fetches with either >> > current_company/office so that I can easily tell that they are >> > properly scoped to the current application instance. >> >> > Anyway I''m probably being a bit anal, but just wondered if anyone has >> > any ideas. >> >> > Many thanks! >> >> > -- >> > You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. >> > To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org. >> > To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org >> > For more options, visit this group athttp://groups.google.com/group/rubyonrails-talk?hl=en. > > -- > You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. > To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org > To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe@googlegroups.com. > For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en. > > > >-- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
Hi Ginty, I think it''s as simple as this: @items = Item.all(:conditions => [ "office_id = ? OR (company_id = ? AND shared = 1)", current_office.id, current_company.id ]) - Aleksey On Jan 21, 2:05 pm, Ginty <stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> Hi All, > > I see that named scopes can be used to inject additional AND > conditions into the WHERE component of a query, however is there any > way to inject an OR condition? > > Say for example I have a Company and Office model, the Company > has_many Offices and both the Company and Office own many child > models. > > The Office should be able to see the child models that he specifically > owns, but also those owned by his parent company that have been > designated to be shared throughout the company. > > So what I really want to do is something like: > > @items = current_office.items.including_shared > > where the including_shared scope would have to inject a condition like > ''OR (company_id = x AND shared = 1)'' into the query. > However I can''t see a way to do this. > > I can get the results I want from either: > > @items = current_office.items > @items << current_company.items.shared > > or using a single scope on the Item class: > > Item.for_current_office_and_shared > > However I don''t like that the first one requires two db calls, and for > the second one I prefer to start all fetches with either > current_company/office so that I can easily tell that they are > properly scoped to the current application instance. > > Anyway I''m probably being a bit anal, but just wondered if anyone has > any ideas. > > Many thanks!-- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
Thanks guys, that got me thinking about it in a different way.
In reality I have a lot of models with this type of ownership and I
ended up going with this in the office model:
# This implements things like:
current_office.holidays_including_shared
def method_missing(method_id)
if method_id.to_s =~ /(.+)_including_shared/
$1.singularize.camelize.constantize.all(:conditions =>
["office_id = ? OR (company_id = ? AND shared = true)", self.id,
self.company_id])
else
super
end
end
So this gets me exactly what I wanted with my controller call down to
a clean single line where it is easy to see the scope and the single
DB query.
Cheers!
On Jan 21, 4:58 pm, Aleksey Gureiev
<spyro...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:> Hi Ginty,
>
> I think it''s as simple as this:
>
> @items = Item.all(:conditions => [ "office_id = ? OR (company_id =
?
> AND shared = 1)", current_office.id, current_company.id ])
>
> - Aleksey
>
> On Jan 21, 2:05 pm, Ginty
<stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > Hi All,
>
> > I see that named scopes can be used to inject additional AND
> > conditions into the WHERE component of a query, however is there any
> > way to inject an OR condition?
>
> > Say for example I have a Company and Office model, the Company
> > has_many Offices and both the Company and Office own many child
> > models.
>
> > The Office should be able to see the child models that he specifically
> > owns, but also those owned by his parent company that have been
> > designated to be shared throughout the company.
>
> > So what I really want to do is something like:
>
> > @items = current_office.items.including_shared
>
> > where the including_shared scope would have to inject a condition like
> > ''OR (company_id = x AND shared = 1)'' into the query.
> > However I can''t see a way to do this.
>
> > I can get the results I want from either:
>
> > @items = current_office.items
> > @items << current_company.items.shared
>
> > or using a single scope on the Item class:
>
> > Item.for_current_office_and_shared
>
> > However I don''t like that the first one requires two db
calls, and for
> > the second one I prefer to start all fetches with either
> > current_company/office so that I can easily tell that they are
> > properly scoped to the current application instance.
>
> > Anyway I''m probably being a bit anal, but just wondered if
anyone has
> > any ideas.
>
> > Many thanks!
--
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Except it doesn''t bloody work at all!
It worked like a dream in my unit test but failed when attempted in a
controller.
It seems that within the controller environment rails does some
trickery to implement the has_xxxx relationships, and while
current_office.class tells me it is an Office, it is actually an
ActiveRecord AssociationProxy, sneaky.
So if anyone is ever interested in implementing something similar then
note the following...
The AssociationProxy gives the target model (the Office in this case)
the first attempt at fulfilling a method call by checking if it has
the method via respond_to?
In this case the Office does not have a method called
''items_including_shared'' and so it returns false and then the
call
falls through to the AssociationProxy#method_missing which has no idea
what to do with it.
So to make this work you need to override the respond_to? method to
account for the fact that the Office model can actually handle these
additional methods that are not explicitly declared.
Here is my final code:
# This implements things like
current_office.holidays_including_shared
def method_missing(method_id, *arguments)
if item = method_contains_including_shared(method_id)
item.singularize.camelize.constantize.all(:conditions =>
["office_id = ? OR (company_id = ? AND shared = true)",
self.id, self.company_id])
else
super
end
end
# Returns true for any explicitly declared methods or anything
ending in _including_shared
def respond_to?(method)
!!method_contains_including_shared(method) || super
end
protected
def method_contains_including_shared(method)
method.to_s =~ /(.+)_including_shared/ ? $1 : false
end
On Jan 21, 9:09 pm, Ginty
<stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:> Thanks guys, that got me thinking about it in a different way.
>
> In reality I have a lot of models with this type of ownership and I
> ended up going with this in the office model:
>
> # This implements things like:
> current_office.holidays_including_shared
> def method_missing(method_id)
> if method_id.to_s =~ /(.+)_including_shared/
> $1.singularize.camelize.constantize.all(:conditions =>
> ["office_id = ? OR (company_id = ? AND shared = true)", self.id,
> self.company_id])
> else
> super
> end
> end
>
> So this gets me exactly what I wanted with my controller call down to
> a clean single line where it is easy to see the scope and the single
> DB query.
>
> Cheers!
>
> On Jan 21, 4:58 pm, Aleksey Gureiev
<spyro...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > Hi Ginty,
>
> > I think it''s as simple as this:
>
> > @items = Item.all(:conditions => [ "office_id = ? OR
(company_id = ?
> > AND shared = 1)", current_office.id, current_company.id ])
>
> > - Aleksey
>
> > On Jan 21, 2:05 pm, Ginty
<stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > > Hi All,
>
> > > I see that named scopes can be used to inject additional AND
> > > conditions into the WHERE component of a query, however is there
any
> > > way to inject an OR condition?
>
> > > Say for example I have a Company and Office model, the Company
> > > has_many Offices and both the Company and Office own many child
> > > models.
>
> > > The Office should be able to see the child models that he
specifically
> > > owns, but also those owned by his parent company that have been
> > > designated to be shared throughout the company.
>
> > > So what I really want to do is something like:
>
> > > @items = current_office.items.including_shared
>
> > > where the including_shared scope would have to inject a condition
like
> > > ''OR (company_id = x AND shared = 1)'' into the
query.
> > > However I can''t see a way to do this.
>
> > > I can get the results I want from either:
>
> > > @items = current_office.items
> > > @items << current_company.items.shared
>
> > > or using a single scope on the Item class:
>
> > > Item.for_current_office_and_shared
>
> > > However I don''t like that the first one requires two db
calls, and for
> > > the second one I prefer to start all fetches with either
> > > current_company/office so that I can easily tell that they are
> > > properly scoped to the current application instance.
>
> > > Anyway I''m probably being a bit anal, but just wondered
if anyone has
> > > any ideas.
>
> > > Many thanks!
--
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Except it doesn''t bloody work at all!
It worked like a dream in my unit test but failed when attempted in a
controller.
It seems that within the controller environment rails does some
trickery to implement the has_xxxx relationships, and while
current_office.class tells me it is an Office, it is actually an
ActiveRecord AssociationProxy, sneaky.
So if anyone is ever interested in implementing something similar then
note the following...
The AssociationProxy gives the target model (the Office in this case)
the first attempt at fulfilling a method call by checking if it has
the method via respond_to?
In this case the Office does not have a method called
''items_including_shared'' and so it returns false and then the
call
falls through to the AssociationProxy#method_missing which has no idea
what to do with it.
So to make this work you need to override the respond_to? method to
account for the fact that the Office model can actually handle these
additional methods that are not explicitly declared.
Here is my final code:
# This implements things like
current_office.holidays_including_shared
def method_missing(method_id, *arguments)
if item = method_contains_including_shared(method_id)
item.singularize.camelize.constantize.all(:conditions =>
["office_id = ? OR (company_id = ? AND shared = true)",
self.id, self.company_id])
else
super
end
end
# Returns true for any explicitly declared methods or anything
ending in _including_shared
def respond_to?(method)
!!method_contains_including_shared(method) || super
end
protected
def method_contains_including_shared(method)
method.to_s =~ /(.+)_including_shared/ ? $1 : false
end
On Jan 21, 9:09 pm, Ginty
<stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:> Thanks guys, that got me thinking about it in a different way.
>
> In reality I have a lot of models with this type of ownership and I
> ended up going with this in the office model:
>
> # This implements things like:
> current_office.holidays_including_shared
> def method_missing(method_id)
> if method_id.to_s =~ /(.+)_including_shared/
> $1.singularize.camelize.constantize.all(:conditions =>
> ["office_id = ? OR (company_id = ? AND shared = true)", self.id,
> self.company_id])
> else
> super
> end
> end
>
> So this gets me exactly what I wanted with my controller call down to
> a clean single line where it is easy to see the scope and the single
> DB query.
>
> Cheers!
>
> On Jan 21, 4:58 pm, Aleksey Gureiev
<spyro...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > Hi Ginty,
>
> > I think it''s as simple as this:
>
> > @items = Item.all(:conditions => [ "office_id = ? OR
(company_id = ?
> > AND shared = 1)", current_office.id, current_company.id ])
>
> > - Aleksey
>
> > On Jan 21, 2:05 pm, Ginty
<stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > > Hi All,
>
> > > I see that named scopes can be used to inject additional AND
> > > conditions into the WHERE component of a query, however is there
any
> > > way to inject an OR condition?
>
> > > Say for example I have a Company and Office model, the Company
> > > has_many Offices and both the Company and Office own many child
> > > models.
>
> > > The Office should be able to see the child models that he
specifically
> > > owns, but also those owned by his parent company that have been
> > > designated to be shared throughout the company.
>
> > > So what I really want to do is something like:
>
> > > @items = current_office.items.including_shared
>
> > > where the including_shared scope would have to inject a condition
like
> > > ''OR (company_id = x AND shared = 1)'' into the
query.
> > > However I can''t see a way to do this.
>
> > > I can get the results I want from either:
>
> > > @items = current_office.items
> > > @items << current_company.items.shared
>
> > > or using a single scope on the Item class:
>
> > > Item.for_current_office_and_shared
>
> > > However I don''t like that the first one requires two db
calls, and for
> > > the second one I prefer to start all fetches with either
> > > current_company/office so that I can easily tell that they are
> > > properly scoped to the current application instance.
>
> > > Anyway I''m probably being a bit anal, but just wondered
if anyone has
> > > any ideas.
>
> > > Many thanks!
--
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blog.noizeramp.com/2009/12/30/our-toyota/
2010-Jan-22 11:19 UTC
Re: How to generate OR conditions in a scope
I''m sure you are overcomplicating matters. Let me give you another
idea, and see if you like it. :)
The missing_method is known to be relatively slow and I wouldn''t rely
on it in a high traffic situation. What you are trying to do can
usually be done by adding a custom finder to the Item class, or if you
foresee more parameters to be added, by using a named scope. So
instead of doing "_including_shared" magic, you could simply do this
with named scopes:
class Item < ActiveRecord::Base
named_scope :shared_by, lambda { |office| { :conditions =>
[ "office_id = ? OR (company_id = ? AND shared = true)", office.id,
office.company_id] }}
end
After this, you could do this kind of queries:
@items = Item.shared_by(current_office).all
or
@items = Item.shared_by(current_office).all(:limit => 5, :conditions
=> { :visible => true })
or... you get the idea.
If you want to reuse the named_scope definition across multiple
models, you can move it into a separate module and include / extend it
in your models to stay DRY.
- Aleksey
On Jan 22, 3:32 pm, Ginty
<stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
wrote:> Except it doesn''t bloody work at all!
>
> It worked like a dream in my unit test but failed when attempted in a
> controller.
>
> It seems that within the controller environment rails does some
> trickery to implement the has_xxxx relationships, and while
> current_office.class tells me it is an Office, it is actually an
> ActiveRecord AssociationProxy, sneaky.
>
> So if anyone is ever interested in implementing something similar then
> note the following...
>
> The AssociationProxy gives the target model (the Office in this case)
> the first attempt at fulfilling a method call by checking if it has
> the method via respond_to?
> In this case the Office does not have a method called
> ''items_including_shared'' and so it returns false and then
the call
> falls through to the AssociationProxy#method_missing which has no idea
> what to do with it.
>
> So to make this work you need to override the respond_to? method to
> account for the fact that the Office model can actually handle these
> additional methods that are not explicitly declared.
>
> Here is my final code:
>
> # This implements things like
> current_office.holidays_including_shared
> def method_missing(method_id, *arguments)
> if item = method_contains_including_shared(method_id)
> item.singularize.camelize.constantize.all(:conditions =>
> ["office_id = ? OR (company_id = ? AND shared = true)",
>
> self.id, self.company_id])
> else
> super
> end
> end
>
> # Returns true for any explicitly declared methods or anything
> ending in _including_shared
> def respond_to?(method)
> !!method_contains_including_shared(method) || super
> end
>
> protected
>
> def method_contains_including_shared(method)
> method.to_s =~ /(.+)_including_shared/ ? $1 : false
> end
>
> On Jan 21, 9:09 pm, Ginty
<stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
>
>
> > Thanks guys, that got me thinking about it in a different way.
>
> > In reality I have a lot of models with this type of ownership and I
> > ended up going with this in the office model:
>
> > # This implements things like:
> > current_office.holidays_including_shared
> > def method_missing(method_id)
> > if method_id.to_s =~ /(.+)_including_shared/
> > $1.singularize.camelize.constantize.all(:conditions =>
> > ["office_id = ? OR (company_id = ? AND shared = true)",
self.id,
> > self.company_id])
> > else
> > super
> > end
> > end
>
> > So this gets me exactly what I wanted with my controller call down to
> > a clean single line where it is easy to see the scope and the single
> > DB query.
>
> > Cheers!
>
> > On Jan 21, 4:58 pm, Aleksey Gureiev
<spyro...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > > Hi Ginty,
>
> > > I think it''s as simple as this:
>
> > > @items = Item.all(:conditions => [ "office_id = ? OR
(company_id = ?
> > > AND shared = 1)", current_office.id, current_company.id ])
>
> > > - Aleksey
>
> > > On Jan 21, 2:05 pm, Ginty
<stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>
> > > > Hi All,
>
> > > > I see that named scopes can be used to inject additional AND
> > > > conditions into the WHERE component of a query, however is
there any
> > > > way to inject an OR condition?
>
> > > > Say for example I have a Company and Office model, the
Company
> > > > has_many Offices and both the Company and Office own many
child
> > > > models.
>
> > > > The Office should be able to see the child models that he
specifically
> > > > owns, but also those owned by his parent company that have
been
> > > > designated to be shared throughout the company.
>
> > > > So what I really want to do is something like:
>
> > > > @items = current_office.items.including_shared
>
> > > > where the including_shared scope would have to inject a
condition like
> > > > ''OR (company_id = x AND shared = 1)'' into
the query.
> > > > However I can''t see a way to do this.
>
> > > > I can get the results I want from either:
>
> > > > @items = current_office.items
> > > > @items << current_company.items.shared
>
> > > > or using a single scope on the Item class:
>
> > > > Item.for_current_office_and_shared
>
> > > > However I don''t like that the first one requires
two db calls, and for
> > > > the second one I prefer to start all fetches with either
> > > > current_company/office so that I can easily tell that they
are
> > > > properly scoped to the current application instance.
>
> > > > Anyway I''m probably being a bit anal, but just
wondered if anyone has
> > > > any ideas.
>
> > > > Many thanks!
--
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Hi Aleksey, I think it just comes down to preference really and I prefer the idea of a having a common rule that I start all finders with current_office and then I instantly know that I have safely scoped it to the current application instance. Of course you way would work to, I just think that mine looks nicer! current_office.items current_office.items_including_shared looks nicer and is more intuitive than... current_office.items Item.shared_by(current_office).all I don''t think concerns about using method_missing are valid at this stage in the game, that''s how all rails'' dynamic finders work after all. Thanks again! On Jan 22, 5:19 am, "blog.noizeramp.com/2009/12/30/our-toyota/" <spyro...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:> I''m sure you are overcomplicating matters. Let me give you another > idea, and see if you like it. :) > > The missing_method is known to be relatively slow and I wouldn''t rely > on it in a high traffic situation. What you are trying to do can > usually be done by adding a custom finder to the Item class, or if you > foresee more parameters to be added, by using a named scope. So > instead of doing "_including_shared" magic, you could simply do this > with named scopes: > > class Item < ActiveRecord::Base > named_scope :shared_by, lambda { |office| { :conditions => > [ "office_id = ? OR (company_id = ? AND shared = true)", office.id, > office.company_id] }} > end > > After this, you could do this kind of queries: > > @items = Item.shared_by(current_office).all > > or > > @items = Item.shared_by(current_office).all(:limit => 5, :conditions > => { :visible => true }) > > or... you get the idea. > > If you want to reuse the named_scope definition across multiple > models, you can move it into a separate module and include / extend it > in your models to stay DRY. > > - Aleksey > > On Jan 22, 3:32 pm, Ginty <stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: > > > Except it doesn''t bloody work at all! > > > It worked like a dream in my unit test but failed when attempted in a > > controller. > > > It seems that within the controller environment rails does some > > trickery to implement the has_xxxx relationships, and while > > current_office.class tells me it is an Office, it is actually an > > ActiveRecord AssociationProxy, sneaky. > > > So if anyone is ever interested in implementing something similar then > > note the following... > > > The AssociationProxy gives the target model (the Office in this case) > > the first attempt at fulfilling a method call by checking if it has > > the method via respond_to? > > In this case the Office does not have a method called > > ''items_including_shared'' and so it returns false and then the call > > falls through to the AssociationProxy#method_missing which has no idea > > what to do with it. > > > So to make this work you need to override the respond_to? method to > > account for the fact that the Office model can actually handle these > > additional methods that are not explicitly declared. > > > Here is my final code: > > > # This implements things like > > current_office.holidays_including_shared > > def method_missing(method_id, *arguments) > > if item = method_contains_including_shared(method_id) > > item.singularize.camelize.constantize.all(:conditions => > > ["office_id = ? OR (company_id = ? AND shared = true)", > > > self.id, self.company_id]) > > else > > super > > end > > end > > > # Returns true for any explicitly declared methods or anything > > ending in _including_shared > > def respond_to?(method) > > !!method_contains_including_shared(method) || super > > end > > > protected > > > def method_contains_including_shared(method) > > method.to_s =~ /(.+)_including_shared/ ? $1 : false > > end > > > On Jan 21, 9:09 pm, Ginty <stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: > > > > Thanks guys, that got me thinking about it in a different way. > > > > In reality I have a lot of models with this type of ownership and I > > > ended up going with this in the office model: > > > > # This implements things like: > > > current_office.holidays_including_shared > > > def method_missing(method_id) > > > if method_id.to_s =~ /(.+)_including_shared/ > > > $1.singularize.camelize.constantize.all(:conditions => > > > ["office_id = ? OR (company_id = ? AND shared = true)", self.id, > > > self.company_id]) > > > else > > > super > > > end > > > end > > > > So this gets me exactly what I wanted with my controller call down to > > > a clean single line where it is easy to see the scope and the single > > > DB query. > > > > Cheers! > > > > On Jan 21, 4:58 pm, Aleksey Gureiev <spyro...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: > > > > > Hi Ginty, > > > > > I think it''s as simple as this: > > > > > @items = Item.all(:conditions => [ "office_id = ? OR (company_id = ? > > > > AND shared = 1)", current_office.id, current_company.id ]) > > > > > - Aleksey > > > > > On Jan 21, 2:05 pm, Ginty <stephen.f.mcgi...-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote: > > > > > > Hi All, > > > > > > I see that named scopes can be used to inject additional AND > > > > > conditions into the WHERE component of a query, however is there any > > > > > way to inject an OR condition? > > > > > > Say for example I have a Company and Office model, the Company > > > > > has_many Offices and both the Company and Office own many child > > > > > models. > > > > > > The Office should be able to see the child models that he specifically > > > > > owns, but also those owned by his parent company that have been > > > > > designated to be shared throughout the company. > > > > > > So what I really want to do is something like: > > > > > > @items = current_office.items.including_shared > > > > > > where the including_shared scope would have to inject a condition like > > > > > ''OR (company_id = x AND shared = 1)'' into the query. > > > > > However I can''t see a way to do this. > > > > > > I can get the results I want from either: > > > > > > @items = current_office.items > > > > > @items << current_company.items.shared > > > > > > or using a single scope on the Item class: > > > > > > Item.for_current_office_and_shared > > > > > > However I don''t like that the first one requires two db calls, and for > > > > > the second one I prefer to start all fetches with either > > > > > current_company/office so that I can easily tell that they are > > > > > properly scoped to the current application instance. > > > > > > Anyway I''m probably being a bit anal, but just wondered if anyone has > > > > > any ideas. > > > > > > Many thanks!-- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.
Ginty wrote:> Hi Aleksey, > > I think it just comes down to preference really and I prefer the idea > of a having a common rule that I start all finders with current_office > and then I instantly know that I have safely scoped it to the current > application instance. > > Of course you way would work to, I just think that mine looks nicer! > > current_office.items > current_office.items_including_sharedBut if named_scopes could do this, then starting with current_office would be meaningless because the records would no longer be scoped to current_office. I think you''re trying to implement a Bad Idea.> > looks nicer and is more intuitive than... > > current_office.items > Item.shared_by(current_office).allBut the latter is more intention-revealing, and will be clearer to read.> > I don''t think concerns about using method_missing are valid at this > stage in the game,Probably true.> that''s how all rails'' dynamic finders work after > all.Sort of. Rails'' dynamic finders actually memoize the method so method_missing is only called the first time around.> > Thanks again! > > On Jan 22, 5:19�am, "blog.noizeramp.com/2009/12/30/our-toyota/"Best, -- Marnen Laibow-Koser http://www.marnen.org marnen-sbuyVjPbboAdnm+yROfE0A@public.gmane.org -- Posted via http://www.ruby-forum.com/. -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to rubyonrails-talk-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To unsubscribe from this group, send email to rubyonrails-talk+unsubscribe@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.