Hi again, Sorry for the inadvertent vowel switch on your name, a problem I experience far too often in the US when mailing lists decide to drop the last letter of my name.
Cheers, Andrea On Tue, Sep 7, 2010 at 7:27 AM, Andreas Kollegger < [email protected]> wrote: > Hi Alexandra, > > Well, you're right that the reference node doesn't have any special > properties or behaviors, except that it is the only node you can always get > without knowing anything else about it. It's a common enough graphing > pattern that it seems more convenient to have it by default. Either it gets > used and can't be deleted (until the relationships have been deleted), or it > gets ignored and can safely be deleted. > > On the pragmatic scale between convenience and correctness, the reference > node admittedly leans towards convenience. It is only a little special, > convenient enough to have, but not special enough to prevent deletion. > > /Andreas > > 2010/9/5 Alexandru Popescu ☀ <[email protected]> > > On Sun, Sep 5, 2010 at 1:00 PM, Anders Nawroth <[email protected]> >> wrote: >> > Hi! >> > >> > Just chiming in on entry points / reference node. >> > >> > 2010-09-03 14:28, Alexandru Popescu ☀ skrev: >> >> This is a very important aspect as I can imagine many systems that can >> >> use a small subset of the existing nodes as entry points. Basically by >> >> using the cached IDs you'll be able to get to these without the need >> >> of using indexing/traversals. >> > >> > This is typically where you should use the reference node: create a >> > relationship with a specific relationship type (like >> > "customers_entry_point") from the reference node to the entry point node >> > (also known as a subreference node). Then there's no need to store the >> > IDs somewhere else. BTW us the >> > Node.getSingleRelationship(RelationshipType, Direction) for this >> > purpose! See: >> > >> http://api.neo4j.org/current/org/neo4j/graphdb/Node.html#getSingleRelationship(org.neo4j.graphdb.RelationshipType >> , >> > org.neo4j.graphdb.Direction) >> > >> > There's also a utility method for using subreference nodes in the utils >> > component: >> > >> http://components.neo4j.org/neo4j-utils/apidocs/org/neo4j/util/GraphDatabaseUtil.html#getOrCreateSubReferenceNode(org.neo4j.graphdb.RelationshipType) >> > >> > /anders >> >> Anders, >> >> That's indeed a nice idea and pretty close to what I've been planning >> to use it for. >> >> But we are digressing from the initial question: is it or is it not a >> special node? >> >> If it is a special node, then do not allow me to delete it. If it is >> not, then do not create it by default. >> >> :- alex >> _______________________________________________ >> Neo4j mailing list >> [email protected] >> https://lists.neo4j.org/mailman/listinfo/user >> > > _______________________________________________ Neo4j mailing list [email protected] https://lists.neo4j.org/mailman/listinfo/user
