Node is deleted and cannot be used to create a relationship

I have a node-link model ( which is a graph ) of an electricity grid in Neo4j, so this should fit like a glove.

The nodes and links are objects of their own, which are traversable in an abstract manner.

Link has a starting node (:Link) – [:begint_bij] –> (:Node) and an ending node (:Link) – [:eindigt_bij] –> (:Node)

Every :Node and :Link has references to one or more objects. Links and Nodes are uniquely defined by their references in this model.

The model is generated by the object-oriented GIS model and because of the generating method ( which I have no influence on ) redundant Node Link (pairs) are in the dataset.

In the picture we see a cloud of Nodes ( purple ) and Links ( green ) surrounding an electricity cable.

In the detail you can see the redundant pairs clearly with a pattern:

A Node-Link pair where the Node has only relationship to ( cables, gisreferences and links ) and the link has only relationships to ( cables, gisreferences and nodes )

For removing the redundant Node-Link pairs I have come up with this query:

call apoc.periodic.iterate (

" MATCH (fld:e_lv_function_cable ) where not exists (fld.done) Return fld",

" match (fld) - [:GenObject] - (fn:Node)

match (fn) - [:begint_bij] - (l1:Link)

with [(fn) - - (obj1) | labels(obj1)] AS conn1, [(l1) - - (obj2) | labels(obj2)] AS conn2, fn, l1, fld

where all( lb1 IN conn1 where lb1[0] in ['e_lv_function_cable','GisReference','Link'] )

and all( lb2 IN conn2 where lb2[0] in ['e_lv_function_cable','GisReference','Node'] )

with l1, fn, fld

match (l1) - [:eindigt_bij] - (n2)

match (l2:Link) - [r] - (fn) - [:begint_bij] - (l1)

Call (

n2 is not null and l2 is not null and r is not null,

'Call apoc.create.relationship (l2, type(r), {}, n2) YIELD rel Detach Delete l1, fn',


{n2: n2, l2: l2, r: r, l1: l1, fn: fn}) YIELD value

with fld

set fld.done=true

", {batchSize:100, parallel:false}) yield batches, total return batches, total

And it does the job.

However in a few cases I get an error ( in the debug log ):

Failed to invoke procedure Caused by: org.neo4j.graphdb.NotFoundException: Node is deleted and cannot be used to create a relationship

And sometimes:

Failed to invoke procedure Caused by: java.lang.IllegalStateException: Kernel API returned non-existent relationship type: -1

And it almost makes sense to me.

Can anyone please:

  • (better) explain to me what is causing this, and
  • Point me t a query that does the job 100%


Hello @marcel.olij and welcome to the Neo4j community :slight_smile:

When you load the nodes and relationships, did you use MERGE?



The redundant nodes are in the input and can't be merged on basis of their ids or rels.



Hello @marcel.olij :slight_smile:

Don't you use unique constraints to create your database?



The nodes and links are themselves unigue in the input, so unique constraints would not do the job.
The software that creates the node link model has a reason to generate these extra node-link pairs ( I don't see what it is though ). They are of no use to me and I want them out for better perfomance and model hygiëne.
If i could use a unique constraint, I still must be able to connect the node-links at import again and that would probably harder than removing these pairs after creation.