On 2/11/07, Bill Moseley <[EMAIL PROTECTED]> wrote:
I'm looking for a little guidance in representing a file system --
well just the file and directory structure of a file system.
Often articles on representing a hierarchy discuss the advantages of
using Nested Sets (or nested intervals) it seems. I'm not clear how
well they apply to a file system-like hierarchy, though.
The examples (and my limited understanding) of Nested Sets have the
leaf nodes at the end of the branches, where in a file system a node
can have both leaf nodes (files) and branches (directories).
Also, the Nested Sets seem to solve problems I don't have -- such as
finding all descendants of a given node.
My simple requirements are:
-- Quickly be able to lookup content by a full "path" name
-- Provide "directory" views that shows parent, list of contents
including any "sub-directories".
-- To be able to easily move branches.
It will not be a large collection of "files" in the tree, so that's
not an issue.
Seems like an Adjacency List along with a de-normalized "path" column
in the leaf nodes would meet the requirements. But, as I see nested
sets discussed so often I wonder which is a better approach.
Can you describe in a little bit more detail about what you mean by
'Adjaceny LIst'?
merlin
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