Fantastic, in my case the ids are exactly the sequence [0, 1, ..., N] without gaps, unique, and in that order.
Thanks both of you for the help! On Monday, June 15, 2015 at 12:34:18 PM UTC-7, Michael Hunger wrote: > > No, --id-type actual > would but then you have to make sure to have globally unique incrementing > id's without large holes in the distribution. > > > Am 15.06.2015 um 21:31 schrieb Zongheng Yang <[email protected] > <javascript:>>: > > I see. Would setting the `--processors 1` flag for neo4j-import make > internal ids and external ids match in my case? (I understand this is an > implementation detail and not a user-facing property.) > > On Monday, June 15, 2015 at 12:07:56 PM UTC-7, Michael Hunger wrote: >> >> GraphDatabaseService#getNodeById(long id) >> >> >> takes Neo4j internal ids. >> >> Michael >> >> Am 15.06.2015 um 20:59 schrieb Zongheng Yang <[email protected]>: >> >> Hi Mattias, >> >> Thanks for looking into this. I understand the difference between Neo4j >> internal ids vs. the ids supplied in the csv. >> >> However for say GraphDatabaseService#getNodeById(long id), does this >> function take the user-supplied ids or Neo4j's internal ids? >> >> If it is the former: then the conceptual mismatch doesn't fully explain >> the problem (e.g. I queried the nodes/edges using user-supplied ids, and >> the internal ids should not mess up with the query results). If it is the >> latter, then for users programming using the Java Core API, how should they >> get these correct internal ids (they only know application-supplied ids). >> >> Best, >> Zongheng >> >> On Monday, June 15, 2015 at 5:23:24 AM UTC-7, Mattias Persson wrote: >>> >>> Hello again, I'm quite confident I know what's happening here. The >>> problem is the misconception that your INTEGER ids defined in the csv files >>> will map 1-to-1 to the neo4j node/relationship ids in the store. They will >>> actually match in most cases, but that's merely a coincidence. >>> >>> What you're seeing is the result of some parallelism happening in the >>> importer where batches of 10k nodes/relationships flows through different >>> steps, where some steps may execute multiple batches in parallel and >>> doesn't care if reordering happens. Ids are assigned at the end. >>> >>> You're looking at the ids and see that they mismatch, but if you look at >>> their data you should see that all relationships match the csv files. So >>> please disregard the seemingly close match of neo4j node/relationship ids >>> with the csv input ids as they are quite different in nature. >>> >>> On Thursday, June 11, 2015 at 11:32:55 AM UTC+2, Mattias Persson wrote: >>>> >>>> Hi, I'm one of the main authors of the import tool and I find this >>>> issue quite interesting. >>>> >>>> Would you be able to share your dataset with me personally, for the >>>> single purpose of trying to find the root cause? >>>> >>>> On Friday, June 5, 2015 at 5:12:43 AM UTC+2, Zongheng Yang wrote: >>>>> >>>>> Hi all, >>>>> >>>>> I'm using neo4j-import to import nodes and relationships from csv >>>>> files. Let's say node id 538398 has about 100 edges and >>>>> >>>>> 538398 -> 370047 >>>>> 538398 -> 379981 >>>>> >>>>> are just two of them. After the import, the neo4j database actually >>>>> >>>>> - *loses* these two edges >>>>> - instead *corrupts* the destination ids, as follows >>>>> >>>>> 538398 -> 380047 >>>>> 538398 -> 389981 >>>>> >>>>> - *keeps* all other outgoing edges of 538398 correct >>>>> >>>>> The problem seems to be non-deterministic: doing a `rm -rf dbPath` and >>>>> re-running neo4j-import seems to fix the issue, for this particular node >>>>> -- >>>>> but I've not done extensive tests to see whether other nodes get >>>>> corrupted >>>>> in this way. >>>>> >>>>> Has anyone seen this before? The graph has on the order of 1 million >>>>> node, average degree 40. >>>>> >>>>> Zongheng >>>>> >>>> >> -- >> You received this message because you are subscribed to the Google Groups >> "Neo4j" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> For more options, visit https://groups.google.com/d/optout. >> >> >> > -- > You received this message because you are subscribed to the Google Groups > "Neo4j" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > For more options, visit https://groups.google.com/d/optout. > > > -- You received this message because you are subscribed to the Google Groups "Neo4j" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
