If you want to use a different
name for your left boundary column, specify that name via the left_column parameter, for
example:
class Comment < ActiveRecord::Base
acts_as_nested_set :left_column => "lower_boundary"
end
right_column
The right_column parameter is analogous to left_column. The right boundary column stores
the highest primary key value plus one that the current record shares a level with. By default,
this column is assumed to be labeled rgt. If you want to use a different name, specify that
name via right_column. The following example specifies higher_boundary as the right boundary
column name:
class Comment < ActiveRecord::Base
acts_as_nested_set :right_column => "higher_boundary"
end
scope
The scope parameter allows you to further limit what is considered a part of a given set. If you
specify a symbol that does not end in _id, then _id will automatically be appended to the symbol.
For example, the following calls to acts_as_nested_set are equivalent:
CHAPTER 5 ?– BONUS FEATURES 102
class Comment < ActiveRecord::Base
acts_as_nested_set :scope => :related #=> actually uses the column related_id
end
class Comment < ActiveRecord::Base
acts_as_nested_set :scope => :related_id #=> actually uses the column related_id
end
If you require even more control on the scope for nested sets, you can simply pass an
entire string that will be used as the where clause.
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