Error "Mixing specified and unspecified group belongings in a single import isn't supported" when using neo4j-import command

Question

I'm trying to import a fair amount of data into Neo4j, which it takes too long to be imported using the LOAD CSV way.

For that reason I'm trying with the neo4j-import command but I got the following error and I haven't found any information about it or what it means exactly. The error is:

 2015-04-29 14:34:06.225+0000 ERROR [org.neo4j]: Error during import Mixing specified and unspecified group belongings in a single import isn't supported
java.lang.RuntimeException: Mixing specified and unspecified group belongings in a single import isn't supported
    at org.neo4j.unsafe.impl.batchimport.staging.StageExecution.stillExecuting(StageExecution.java:62)
    at org.neo4j.unsafe.impl.batchimport.staging.ExecutionSupervisor.anyStillExecuting(ExecutionSupervisor.java:79)
    at org.neo4j.unsafe.impl.batchimport.staging.ExecutionSupervisor.finishAwareSleep(ExecutionSupervisor.java:102)
    at org.neo4j.unsafe.impl.batchimport.staging.ExecutionSupervisor.supervise(ExecutionSupervisor.java:64)
    at org.neo4j.unsafe.impl.batchimport.staging.ExecutionSupervisors.superviseExecution(ExecutionSupervisors.java:80)
    at org.neo4j.unsafe.impl.batchimport.staging.ExecutionSupervisors.superviseDynamicExecution(ExecutionSupervisors.java:59)
    at org.neo4j.unsafe.impl.batchimport.ParallelBatchImporter.executeStages(ParallelBatchImporter.java:239)
    at org.neo4j.unsafe.impl.batchimport.ParallelBatchImporter.doImport(ParallelBatchImporter.java:159)
    at org.neo4j.tooling.ImportTool.main(ImportTool.java:293)
    at org.neo4j.tooling.ImportTool.main(ImportTool.java:227)
Caused by: java.lang.IllegalStateException: Mixing specified and unspecified group belongings in a single import isn't supported
    at org.neo4j.unsafe.impl.batchimport.input.Groups.getOrCreate(Groups.java:53)
    at org.neo4j.unsafe.impl.batchimport.input.csv.InputNodeDeserialization.initialize(InputNodeDeserialization.java:60)
    at org.neo4j.unsafe.impl.batchimport.input.csv.InputEntityDeserializer.initialize(InputEntityDeserializer.java:67)
    at org.neo4j.unsafe.impl.batchimport.input.csv.InputGroupsDeserializer.createNestedIterator(InputGroupsDeserializer.java:74)
    at org.neo4j.unsafe.impl.batchimport.input.csv.InputGroupsDeserializer.createNestedIterator(InputGroupsDeserializer.java:35)
    at org.neo4j.helpers.collection.NestingIterator.fetchNextOrNull(NestingIterator.java:67)
    at org.neo4j.helpers.collection.PrefetchingIterator.peek(PrefetchingIterator.java:60)
    at org.neo4j.helpers.collection.PrefetchingIterator.hasNext(PrefetchingIterator.java:46)
    at org.neo4j.unsafe.impl.batchimport.staging.IteratorBatcherStep.nextBatchOrNull(IteratorBatcherStep.java:53)
    at org.neo4j.unsafe.impl.batchimport.InputIteratorBatcherStep.nextBatchOrNull(InputIteratorBatcherStep.java:41)
    at org.neo4j.unsafe.impl.batchimport.staging.ProducerStep.process(ProducerStep.java:74)
    at org.neo4j.unsafe.impl.batchimport.staging.ProducerStep$1.run(ProducerStep.java:54)

Has someone experienced the same issue or happens to know how what that means?

Thank you very much, Juan M. Sierra

Answer 1

What is a "fair amount of data" ? Please share your file structures / headers?

I presume you have a few columns with :ID(group) and :START_ID(group) and a few without. Make sure that per relationship-file you always have groupings defined.

E.g. :START_ID(group1),:END_ID(group2)

Answer 2

I too had this error, and my problem was that I had defined an "id space" in all but one of my node header files.

I needed to use id spaces because my node identifiers were not unique across all node files (my nodes all had sequential identifiers), so I used this cool feature called an id space: http://neo4j.com/docs/2.2.6/import-tool-header-format.html#_id_spaces

Here is an example that shows the syntax for id spaces: http://neo4j.com/docs/stable/import-tool-id-handling.html

In summary: if you use id spaces, all of your nodes must have their own id spaces. Otherwise you get this error about "Mixing specified and unspecified group belongings in a single import".