LWE work for me on something such as Genre categories for a film. However, when I want to update the film, which it's easiest for me to remove all edges first as there could be additions or subtractions to the genre / actors etc, I am struggling to write a SQL query that should simply do something like
delete edge is_genre from #13:53 (assuming vertex Film is cluster 13, and has out edge 'is_genre' to Genre) this gives the error: java.lang.ClassCastException: com.orientechnologies.common.collection.OMultiCollectionIterator cannot be cast to com.tinkerpop.blueprints.impls.orient.OrientEdge [ONetworkProtocolHttpDb] (Orient 2.0-M3) I would hope something like that would delete the in and outs However, not using LWE, I can do something like delete edge is_genre where out=#13:53 which I can only assume assumes you saying that the SQL is tricky to write for LWE's. How much practically does LWE's save in both memory and query path costs? I won't be working on massive amounts of data, can probably assume around 150k films, each with several genre categories, say 2.5, so for estimations, around 375k edges (there's only 20 genres though so each genre will be have 1000s edges) I hope to be running some complex queries utilising the genre links, hence assumed LWE would be best option (I also have no need to label the edges), but if you feel non-LWE will not impact performance noticeably then I will turn them off Cheers Sky On Thursday, 18 December 2014 09:59:45 UTC, Lvc@ wrote: > > Hi Riccardo, > We removed Lightweight edges by default because it's harder working with > them, specially from SQL. So we preferred simplicity than speed by default, > but they can always be enabled. > > Do you like the new OrientDB T-Shirt? :-) > > Lvc@ > > > On 18 December 2014 at 09:46, Riccardo Tasso <riccard...@gmail.com > <javascript:>> wrote: >> >> Hi, >> since in the new Orient 2.0 there will be Lightweight Edges (LE) >> disabled by default I would like to ask which are the benefits and cost of >> one approach instead of the other. >> >> Of course I see that LE can't have other properties than label. LE will >> require less space, since no records are created on the database. >> Are there other benefits in terms of cost of inserting/updating/deleting >> a new edge? >> Which performance differences can I expect in a traversal with or without >> LE? >> >> I'd like to see this kind of discussion inside documentation, which I >> guess will be updated soon (since it states LE are the default): >> http://www.orientechnologies.com/docs/last/orientdb.wiki/Tutorial-Working-with-graphs.html >> >> Cheers, >> Riccardo >> >> P.S. I have my orient t-shirt right now, thank you guys! >> >> -- >> >> --- >> You received this message because you are subscribed to the Google Groups >> "OrientDB" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to orient-databa...@googlegroups.com <javascript:>. >> For more options, visit https://groups.google.com/d/optout. >> > -- --- You received this message because you are subscribed to the Google Groups "OrientDB" group. To unsubscribe from this group and stop receiving emails from it, send an email to orient-database+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
