Find lowest common ancestor in a in a tree using the Adjacency list model

[Jorgen Andersson]

I'm having a tree structure using the Adjacency list model, having an ID and ParentID for every node in the tree. I need to find the lowest common ancestor for two or more IDs. Anyone that knows how to do this? (I know how to do it with the path enumeration or nested set model, but that doesn't help me here)

[Mycroft Holmes]

Jörgen Andersson wrote:

using the Adjacency list model

I'm curious, what is this? What database are you using? Does this model dictate the format of your keys? I use the hierarchyid in SQL Server to store my structures. How you would achieve this is dependant on your data structure.

Never underestimate the power of human stupidity RAH

[Jorgen Andersson]

Adjacency_list[^] is what Joe Celko calls what probably is the most common representation of a tree in a database. Where every node has an ID and also stores the id of its parent. I'm using Oracle

[Mycroft Holmes]

Thank you, I'm sorry not to be able to help, I have not used Oracle in a decade or so.

Never underestimate the power of human stupidity RAH