Can someone describe the nested set model from a C#/LINQ perspective?

I know the nested set model doesn't pertain to the C# language or LINQ directly... it's what I'm using to develop my web app.

For hierarchical data (categories with sub-categories in my case), I'm currently using something similar to the Adjacency List model. At the moment, I've only got 2 levels of categories, but I'd like to take it further and allow for n levels of categories using the nested set model.

I'm not quite clear on how to use it in a C# context. Here's the article I'm reading on the nested set model. Though this article cleared up my confusion some, I still have a big ?? in my head:

- Is inserting, updating or deleting categories tedious? It look开发者_JS百科s like the left and right numbers would require re-numbering... what would the LINQ queries look like for the following scenarios?

• Delete a child node (re-number all node's left/right values)
• Delete a parent node (what do you do with the orphans?)
• Move a child node to a different parent node (renumber again)

If my understanding is correct, at all times the child node's left/right values will always be between the parent node's left/right values, am I correct?

Seems easy enough, if only the categories were static... most likely I need to spend more time to get my head around the concept.

Any help is greatly appreciated!