Removed named scopes from the finders guide. Named scopes deserve it's own guide

1 files changed, 2 insertions, 120 deletions

diff --git a/railties/guides/source/active_record_querying.textile b/railties/guides/source/active_record_querying.textile
index 139d9f31c6..817d24de1f 100644
--- a/railties/guides/source/active_record_querying.textile
+++ b/railties/guides/source/active_record_querying.textile
@@ -782,125 +782,6 @@ h3. select_all
 Client.connection.select_all("SELECT * FROM clients WHERE id = '1'")
 </ruby>
 
-h3. Working with Associations
-
-When you define a has_many association on a model you get the +find+ method and dynamic finders also on that association. This is helpful for finding associated records within the scope of an existing record, for example finding all the orders for a client that have been sent and not received by doing something like +Client.find(params[:id]).orders.find_by_sent_and_received(true, false)+. Having this find method available on associations is extremely helpful when using nested resources.
-
-h3. Named Scopes
-
-Named scopes are another way to add custom finding behavior to the models in the application. Named scopes provide an object-oriented way to narrow the results of a query.
-
-h4. Simple Named Scopes
-
-Suppose we want to find all clients who are male. You could use this code:
-
-<ruby>
-class Client < ActiveRecord::Base
-  named_scope :males, :conditions => { :gender => "male" }
-end
-</ruby>
-
-Then you could call +Client.males.all+ to get all the clients who are male. Please note that if you do not specify the +all+ on the end you will get a +Scope+ object back, not a set of records which you do get back if you put the +all+ on the end.
-
-If you wanted to find all the clients who are active, you could use this:
-
-<ruby>
-class Client < ActiveRecord::Base
-  named_scope :active, :conditions => { :active => true }
-end
-</ruby>
-
-You can call this new named_scope with +Client.active.all+ and this will do the same query as if we just used +Client.all(:conditions => ["active = ?", true])+. If you want to find the first client within this named scope you could do +Client.active.first+.
-
-h4. Combining Named Scopes
-
-If you wanted to find all the clients who are active and male you can stack the named scopes like this:
-
-<ruby>
-Client.males.active.all
-</ruby>
-
-If you would then like to do a +all+ on that scope, you can. Just like an association, named scopes allow you to call +all+ on them:
-
-<ruby>
-Client.males.active.all(:conditions => ["age > ?", params[:age]])
-</ruby>
-
-h4. Runtime Evaluation of Named Scope Conditions
-
-Consider the following code:
-
-<ruby>
-class Client < ActiveRecord::Base
-  named_scope :recent, :conditions => { :created_at > 2.weeks.ago }
-end
-</ruby>
-
-This looks like a standard named scope that defines a method called +recent+ which gathers all records created any time between now and 2 weeks ago. That's correct for the first time the model is loaded but for any time after that, +2.weeks.ago+ is set to that same value, so you will consistently get records from a certain date until your model is reloaded by something like your application restarting. The way to fix this is to put the code in a lambda block:
-
-<ruby>
-class Client < ActiveRecord::Base
-  named_scope :recent, lambda { { :conditions => ["created_at > ?", 2.weeks.ago] } }
-end
-</ruby>
-
-And now every time the +recent+ named scope is called, the code in the lambda block will be executed, so you'll get actually 2 weeks ago from the code execution, not 2 weeks ago from the time the model was loaded.
-
-h4. Named Scopes with Multiple Models
-
-In a named scope you can use +:include+ and +:joins+ options just like in +find+.
-
-<ruby>
-class Client < ActiveRecord::Base
-  named_scope :active_within_2_weeks
-    lambda { { :joins => :order, :conditions => ["orders.created_at > ?", 2.weeks.ago] } }
-end
-</ruby>
-
-This method, called as +Client.active_within_2_weeks.all+, will return all clients who have placed orders in the past 2 weeks.
-
-h4. Arguments to Named Scopes
-
-If you want to pass to a named scope a required argument, just specify it as a block argument like this:
-
-<ruby>
-class Client < ActiveRecord::Base
-  named_scope :recent, lambda { |time| { :conditions => ["created_at > ?", time] } }
-end
-</ruby>
-
-This will work if you call +Client.recent(2.weeks.ago).all+ but not if you call +Client.recent+. If you want to add an optional argument for this, you have to use prefix the arugment with an *.
-
-<ruby>
-class Client < ActiveRecord::Base
-  named_scope :recent, lambda { |*args| { :conditions => ["created_at > ?", args.first || 2.weeks.ago] } }
-end
-</ruby>
-
-This will work with +Client.recent(2.weeks.ago).all+ and +Client.recent.all+, with the latter always returning records with a created_at date between right now and 2 weeks ago.
-
-Remember that named scopes are stackable, so you will be able to do +Client.recent(2.weeks.ago).unlocked.all+ to find all clients created between right now and 2 weeks ago and have their locked field set to false.
-
-h4. Anonymous Scopes
-
-All Active Record models come with a named scope named +scoped+, which allows you to create anonymous scopes. For example:
-
-<ruby>
-class Client < ActiveRecord::Base
-  def self.recent
-    scoped :conditions => ["created_at > ?", 2.weeks.ago]
-  end
-end
-</ruby>
-
-Anonymous scopes are most useful to create scopes "on the fly":
-
-<ruby>
-Client.scoped(:conditions => { :gender => "male" })
-</ruby>
-
-Just like named scopes, anonymous scopes can be stacked, either with other anonymous scopes or with regular named scopes.
-
 h3. Existence of Objects
 
 If you simply want to check for the existence of the object there's a method called +exists?+. This method will query the database using the same query as +find+, but instead of returning an object or collection of objects it will return either +true+ or false+.
@@ -1007,4 +888,5 @@ h3. Changelog
 
 "Lighthouse ticket":http://rails.lighthouseapp.com/projects/16213-rails-guides/tickets/16
 
-* December 29 2008: Initial version by Ryan Bigg
+* February 7, 2009: Second version by "Pratik":credits.html#lifo
+* December 29 2008: Initial version by "Ryan Bigg":credits.html#radar