Comments on: 7 Tree Data Structure Plugins for Rails http://www.railsinside.com/plugins/164-7-tree-data-structure-plugins-for-rails.html Daily Rails news, views, tips, and joy Sat, 13 Mar 2010 09:39:30 +0000 http://wordpress.org/?v=2.8.4 hourly 1 By: Stefan Kroes http://www.railsinside.com/plugins/164-7-tree-data-structure-plugins-for-rails.html/comment-page-1#comment-1120 Stefan Kroes Fri, 23 Oct 2009 07:10:48 +0000 http://www.railsinside.com/?p=164#comment-1120 I recently created another plugin with the same purpose. The description on github: Ancestry allows the records of a Ruby on Rails ActiveRecord model to be organised as a tree structure (or hierarchy). It uses a single, intuitively formatted database column, using a variation on the materialised path pattern. It exposes all the standard tree structure relations (ancestors, parent, root, children, siblings, descendants) and all of them can be fetched in a single sql query. Additional features are named_scopes, depth caching, depth constraints, easy migration from older plugins/gems, integrity checking, integrity restoration, arrangement of (sub)tree into hashes and different strategies for dealing with orphaned records. You can find the gem at: http://github.com/stefankroes/ancestry I recently created another plugin with the same purpose. The description on github:

Ancestry allows the records of a Ruby on Rails ActiveRecord model to be organised as a tree structure (or hierarchy). It uses a single, intuitively formatted database column, using a variation on the materialised path pattern. It exposes all the standard tree structure relations (ancestors, parent, root, children, siblings, descendants) and all of them can be fetched in a single sql query. Additional features are named_scopes, depth caching, depth constraints, easy migration from older plugins/gems, integrity checking, integrity restoration, arrangement of (sub)tree into hashes and different strategies for dealing with orphaned records.

You can find the gem at: http://github.com/stefankroes/ancestry

]]> By: Mike Karolow http://www.railsinside.com/plugins/164-7-tree-data-structure-plugins-for-rails.html/comment-page-1#comment-347 Mike Karolow Sun, 28 Dec 2008 21:43:05 +0000 http://www.railsinside.com/?p=164#comment-347 I've been trying for google for a concept, but can't come up with a the keywords necessary. I'd like to find a plugin designed to help query data sets that are arbitrarily self referential. All of these plugins seem follow the idea that each object has one path through the tree. I'm looking for a plugin that can help find the full set of ancestors and descendants of an object that can have an arbitrary number of parents or children. As an example, think of a server. It has dependancies on other servers and other servers depend upon it. A group of 10 might have 30 different interdependencies, which makes it difficult to see what "goes down" if one is unplugged. I've been trying for google for a concept, but can't come up with a the keywords necessary. I'd like to find a plugin designed to help query data sets that are arbitrarily self referential. All of these plugins seem follow the idea that each object has one path through the tree. I'm looking for a plugin that can help find the full set of ancestors and descendants of an object that can have an arbitrary number of parents or children.

As an example, think of a server. It has dependancies on other servers and other servers depend upon it. A group of 10 might have 30 different interdependencies, which makes it difficult to see what "goes down" if one is unplugged.

]]> By: Craig Buchek http://www.railsinside.com/plugins/164-7-tree-data-structure-plugins-for-rails.html/comment-page-1#comment-176 Craig Buchek Thu, 04 Dec 2008 20:54:20 +0000 http://www.railsinside.com/?p=164#comment-176 Looks like the "materialized tree" uses something called "Path Enumeration": http://www.onlamp.com/pub/a/onlamp/2004/08/05/hierarchical_sql.html The comments there are also worth reading, as are Joe Celko's books on SQL. Looks like the "materialized tree" uses something called "Path Enumeration": http://www.onlamp.com/pub/a/onlamp/2004/08/05/hierarchical_sql.html The comments there are also worth reading, as are Joe Celko's books on SQL.

]]> By: RTG http://www.railsinside.com/plugins/164-7-tree-data-structure-plugins-for-rails.html/comment-page-1#comment-164 RTG Thu, 27 Nov 2008 16:30:12 +0000 http://www.railsinside.com/?p=164#comment-164 Thanks for the Overview, are there any other options to reflect hierarchiacal structures as with nested sets and trees? I am just wondering. Since the performance of both solutions is not really promissing for updates and tree operations in huge structures. Thanks for the Overview, are there any other options to reflect hierarchiacal structures as with nested sets and trees? I am just wondering. Since the performance of both solutions is not really promissing for updates and tree operations in huge structures.

]]> By: Eric Anderson http://www.railsinside.com/plugins/164-7-tree-data-structure-plugins-for-rails.html/comment-page-1#comment-163 Eric Anderson Wed, 26 Nov 2008 18:11:36 +0000 http://www.railsinside.com/?p=164#comment-163 Thank you for this overview. I have an upcoming project that will need a tree and this article pointed me to several projects I did not know about. Thank you for this overview. I have an upcoming project that will need a tree and this article pointed me to several projects I did not know about.

]]>