diff options
Diffstat (limited to 'activerecord/lib/active_record/acts/nested_set.rb')
| -rw-r--r-- | activerecord/lib/active_record/acts/nested_set.rb | 26 |
1 files changed, 13 insertions, 13 deletions
diff --git a/activerecord/lib/active_record/acts/nested_set.rb b/activerecord/lib/active_record/acts/nested_set.rb index cc120cad4b..8b02b358a9 100644 --- a/activerecord/lib/active_record/acts/nested_set.rb +++ b/activerecord/lib/active_record/acts/nested_set.rb @@ -7,17 +7,17 @@ module ActiveRecord end # This acts provides Nested Set functionality. Nested Set is similiar to Tree, but with - # the added feature that you can select the children and all of it's descendants with + # the added feature that you can select the children and all of their descendents with # a single query. A good use case for this is a threaded post system, where you want # to display every reply to a comment without multiple selects. # # A google search for "Nested Set" should point you in the direction to explain the - # data base theory. I figured a bunch of this from + # database theory. I figured out a bunch of this from # http://threebit.net/tutorials/nestedset/tutorial1.html # - # Instead of picturing a leaf node structure with child pointing back to their parent, + # Instead of picturing a leaf node structure with children pointing back to their parent, # the best way to imagine how this works is to think of the parent entity surrounding all - # of it's children, and it's parent surrounding it, etc. Assuming that they are lined up + # of its children, and its parent surrounding it, etc. Assuming that they are lined up # horizontally, we store the left and right boundries in the database. # # Imagine: @@ -42,7 +42,7 @@ module ActiveRecord # | |___________________________| |___________________________| | # |___________________________________________________________________| # - # The numbers represent the left and right boundries. The table them might + # The numbers represent the left and right boundries. The table then might # look like this: # ID | PARENT | LEFT | RIGHT | DATA # 1 | 0 | 1 | 14 | root @@ -63,10 +63,10 @@ module ActiveRecord # There are instance methods for all of these. # # The structure is good if you need to group things together; the downside is that - # keeping data integrity is a pain, and both adding and removing and entry + # keeping data integrity is a pain, and both adding and removing an entry # require a full table write. # - # This sets up a before_destroy trigger to prune the tree correctly if one of it's + # This sets up a before_destroy trigger to prune the tree correctly if one of its # elements gets deleted. # module ClassMethods @@ -134,10 +134,10 @@ module ActiveRecord end - # Added a child to this object in the tree. If this object hasn't been initialized, + # Adds a child to this object in the tree. If this object hasn't been initialized, # it gets set up as a root node. Otherwise, this method will update all of the - # other elements in the tree and shift them to the right. Keeping everything - # balanaced. + # other elements in the tree and shift them to the right, keeping everything + # balanced. def add_child( child ) self.reload child.reload @@ -179,17 +179,17 @@ module ActiveRecord return (self[right_col_name] - self[left_col_name] - 1)/2 end - # Returns a set of itself and all of it's nested children + # Returns a set of itself and all of its nested children def full_set self.class.find(:all, :conditions => "#{scope_condition} AND (#{left_col_name} BETWEEN #{self[left_col_name]} and #{self[right_col_name]})" ) end - # Returns a set of all of it's children and nested children + # Returns a set of all of its children and nested children def all_children self.class.find(:all, :conditions => "#{scope_condition} AND (#{left_col_name} > #{self[left_col_name]}) and (#{right_col_name} < #{self[right_col_name]})" ) end - # Returns a set of only this entries immediate children + # Returns a set of only this entry's immediate children def direct_children self.class.find(:all, :conditions => "#{scope_condition} and #{parent_column} = #{self.id}") end |