Walking a hierarchy table with Linq

Posted by Retrocoder on Stack Overflow See other posts from Stack Overflow or by Retrocoder
Published on 2010-04-01T12:36:37Z Indexed on 2010/04/01 14:13 UTC
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linq-to-entities

I have a table with two columns, GroupId and ParentId (both are GUIDS). The table forms a hierarchy so I can look for a value in the “GroupId” filed, when I have found it I can look at its ParentId. This ParentId will also appear in the GroupId of a different record. I can use this to walk up the hierarchy tree from any point to the root (root is an empty GUID). What I’d like to do is get a list of records when I know a GroupId. This would be the record with the GroupId and all the parents back to the root record. Is this possible with Linq and if so, can anyone provide a code snippet?

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