Sha256: 84c531b2107c1df7c80663b8fa252dfb727a16639e1561df6303b8eaa1608e5a
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Size: 1.18 KB
Versions: 52
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Stored size: 1.18 KB
Contents
class ChangeTaxonsToNestedSet < ActiveRecord::Migration
def self.up
add_column :taxons, :lft, :integer
add_column :taxons, :rgt, :integer
Taxon.reset_column_information # So the new root ids get saved
Taxon.class_eval do
# adapted from awesome nested set to use "position" information
indices = {}
left_column_name = "lft"
right_column_name = "rgt"
quoted_parent_column_name = "parent_id"
scope = lambda{|node|}
set_left_and_rights = lambda do |node|
# set left
node[left_column_name] = indices[scope.call(node)] += 1
# find
where("#{quoted_parent_column_name} = ?", node).order("position ASC").each{ |n| set_left_and_rights.call(n) }
# set right
node[right_column_name] = indices[scope.call(node)] += 1
node.save!
end
# Find root node(s)
where("#{quoted_parent_column_name} IS NULL").order("position ASC").each do |root_node|
# setup index for this scope
indices[scope.call(root_node)] ||= 0
set_left_and_rights.call(root_node)
end
end
end
def self.down
remove_column :taxons, :lft
remove_column :taxons, :rgt
end
end
Version data entries
52 entries across 40 versions & 9 rubygems