Hello, We're building an application using mainly tree, more then real graphs, but with sometimes some specific relationships between nodes of different trees. We're kind of trying to use Neo4j for extended OLAP things (like including an external dimension (i.e. a tree) inside another dimension (i.e. another tree))
We're really happy with Neo4j, and this mail about "what would you like to have for trees" is even better :) Thanks a lot ! Here are some tree-features we would love to have (I can explain more some of them if needed) : - As we can "embed" a tree to another, an "isTree" feature would be great to ensure the resulting tree will not cause some infinite loop. For now we're using the shortPath GraphAlgo between the two nodes to link - We need some ranking in the trees. As relationships are not ordered, we solved this by adding 3 relationshipTypes in addition of the usual "child" relationships. New relationships are "first child", "last child" and "next child" between each child. Because of this, we can't use typical traversal if we want to traverse the tree in the right order. (Same thing if we used a rank property instead of new relationshipTypes) - In a graph, "delete cascade" behaviour is dangerous, and I think I already saw some mails about that. But for trees, a "delete cascade" features makes sense I guess To answer more specifically to the question about queries, here are our typical queries : - Retreve a tree from a node and for a defined depth - Find the aggregation of a complexe operation executed on every child node recursively (the complexe operation can use properties or other types of links - Filtering results obtained by the previous query - Exclude some nodes in the tree for some calculations Hope all this will help, and thanks again for Neo4j :) Christophe. Andres Taylor wrote > > A subset of the graphs are trees, and they have a few problems that are > specific for them. I'm right now planning what needs to be added to Cypher > to make it play nice with your tree structures. > > I'd love to know if you have hierarchical data, and what queries you do > and > would like to do. Doesn't matter if you use Cypher or not. > > Thanks! > > Andrés > -- View this message in context: http://neo4j-community-discussions.438527.n3.nabble.com/Neo4j-Cypher-3-Trees-tp3567444p3569732.html Sent from the Neo4j Community Discussions mailing list archive at Nabble.com. _______________________________________________ NOTICE: THIS MAILING LIST IS BEING SWITCHED TO GOOGLE GROUPS, please register and consider posting at https://groups.google.com/forum/#!forum/neo4j Neo4j mailing list User@lists.neo4j.org https://lists.neo4j.org/mailman/listinfo/user
