diff options
Diffstat (limited to 'activerecord/lib/active_record/relation/query_methods.rb')
| -rw-r--r-- | activerecord/lib/active_record/relation/query_methods.rb | 42 |
1 files changed, 25 insertions, 17 deletions
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb index b6a7c25b4b..3d0709266a 100644 --- a/activerecord/lib/active_record/relation/query_methods.rb +++ b/activerecord/lib/active_record/relation/query_methods.rb @@ -341,13 +341,19 @@ module ActiveRecord # User.where(name: "John", active: true).unscope(where: :name) # == User.where(active: true) # - # Note that this method is more generalized than ActiveRecord::SpawnMethods#except - # because #except will only affect a particular relation's values. It won't wipe - # the order, grouping, etc. when that relation is merged. For example: + # This method is similar to <tt>except</tt>, but unlike + # <tt>except</tt>, it persists across merges: # - # Post.comments.except(:order) + # User.order('email').merge(User.except(:order)) + # == User.order('email') + # + # User.order('email').merge(User.unscope(:order)) + # == User.all + # + # This means it can be used in association definitions: + # + # has_many :comments, -> { unscope where: :trashed } # - # will still have an order if it comes from the default_scope on Comment. def unscope(*args) check_if_method_has_arguments!(:unscope, args) spawn.unscope!(*args) @@ -355,6 +361,7 @@ module ActiveRecord def unscope!(*args) # :nodoc: args.flatten! + self.unscope_values += args args.each do |scope| case scope @@ -420,7 +427,7 @@ module ActiveRecord # === string # # A single string, without additional arguments, is passed to the query - # constructor as a SQL fragment, and used in the where clause of the query. + # constructor as an SQL fragment, and used in the where clause of the query. # # Client.where("orders_count = '2'") # # SELECT * from clients where orders_count = '2'; @@ -552,9 +559,9 @@ module ActiveRecord # Allows you to change a previously set where condition for a given attribute, instead of appending to that condition. # - # Post.where(trashed: true).where(trashed: false) #=> WHERE `trashed` = 1 AND `trashed` = 0 - # Post.where(trashed: true).rewhere(trashed: false) #=> WHERE `trashed` = 0 - # Post.where(active: true).where(trashed: true).rewhere(trashed: false) #=> WHERE `active` = 1 AND `trashed` = 0 + # Post.where(trashed: true).where(trashed: false) # => WHERE `trashed` = 1 AND `trashed` = 0 + # Post.where(trashed: true).rewhere(trashed: false) # => WHERE `trashed` = 0 + # Post.where(active: true).where(trashed: true).rewhere(trashed: false) # => WHERE `active` = 1 AND `trashed` = 0 # # This is short-hand for unscope(where: conditions.keys).where(conditions). Note that unlike reorder, we're only unscoping # the named conditions -- not the entire where statement. @@ -624,12 +631,11 @@ module ActiveRecord self end - # Returns a chainable relation with zero records, specifically an - # instance of the <tt>ActiveRecord::NullRelation</tt> class. + # Returns a chainable relation with zero records. # - # The returned <tt>ActiveRecord::NullRelation</tt> inherits from Relation and implements the - # Null Object pattern. It is an object with defined null behavior and always returns an empty - # array of records without querying the database. + # The returned relation implements the Null Object pattern. It is an + # object with defined null behavior and always returns an empty array of + # records without querying the database. # # Any subsequent condition chained to the returned relation will continue # generating an empty relation and will not fire any query to the database. @@ -649,7 +655,7 @@ module ActiveRecord # when 'Reviewer' # Post.published # when 'Bad User' - # Post.none # => returning [] instead breaks the previous code + # Post.none # It can't be chained if [] is returned. # end # end # @@ -701,7 +707,7 @@ module ActiveRecord # Specifies table from which the records will be fetched. For example: # # Topic.select('title').from('posts') - # #=> SELECT title FROM posts + # # => SELECT title FROM posts # # Can accept other relation objects. For example: # @@ -976,8 +982,10 @@ module ActiveRecord end def build_select(arel, selects) - unless selects.empty? + if !selects.empty? arel.project(*selects) + elsif from_value + arel.project(Arel.star) else arel.project(@klass.arel_table[Arel.star]) end |