Hello all, I have implemented a new dbic component to manage trees.
It's an alternative method to DBIx::Class::Tree::AdjacencyList and DBIx::Class::Tree::NestedSet. Basically it's the implementation of the general method describe in this paper : http://arxiv.org/pdf/cs.DB/0402051 with this model, you keep the advantage of NestedSet to query descendants without difficulties querying ancestors. Plus the encoding is not volatile (no need to recalculate half of the tree encoding after an insert) and there is a direct correspondence between the materialized path of a node and its encoding. The model is described in the paper are more scalable, but i've yet to make some tests to get an idea how deep you can build down in a tree. This implementation don't use at all the primary key of the table (if any) and don't try to order children. Ordered tree could be a sub component i guess. The only trade-off is that i use 7 (!) columns to do the encoding. github : http://github.com/vdg/DBIx-Class-Tree-Fast Comments and ideas very welcome off course. v.
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