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databases/ruby-dm-is-nested_set,
DataMapper plugin allowing the creation of nested sets from data models
Branch: pkgsrc-2012Q3,
Version: 1.2.0,
Package name: ruby193-dm-is-nested_set-1.2.0,
Maintainer: pkgsrc-usersDataMapper plugin allowing the creation of nested sets from data models.
Provides all the same functionality as dm-is-tree, plus tons more! Read on.
== What is a nested set?
Nested set is a clever model for storing hierarchical data in a flat table.
Instead of (only) storing the id of the parent on each node, a nested set puts
all nodes in a clever structure (see Example below). That is what makes it
possible to get the all of the descendants (not only immediate children),
ancestors, or siblings, in one single query to the database.
The only downside to nested sets (compared to trees] is that the queries it
takes to know these things, and to move nodes around in the tree are rather
complex. That is what this plugin takes care of (+ lots of other neat stuff)!
Nested sets are a good choice for most kinds of ordered trees with more than
two levels of nesting. Very good for menus, categories, and threaded posts.
Master sites:
SHA1: 33777da3df1fe87263014dd096efa16a49b697b6
RMD160: 67806cfeb1024c88fc95a1daf5ab4d9fb7c27e6b
Filesize: 13.5 KB
Version history: (Expand)
- (2012-10-02) Package added to pkgsrc.se, version ruby193-dm-is-nested_set-1.2.0 (created)