apoc.truncate

[eastlondoner]

Feature description (Mandatory)

This should wipe a database without causing an OOM. It will therefore need to not be transactional i.e. if it encounters an error during execution it could result in a partially deleted graph rather than a totally deleted graph.

under the hood it should do something like this:

call apoc.periodic.iterate("cypher runtime=slotted match ()-[r]->() return r","delete r", {batchSize:10000,iterateList:true})
call apoc.periodic.iterate("cypher runtime=slotted match (n) return n","delete n", {batchSize:10000,iterateList:true})

[eastlondoner]

it might make sense to put this in apoc.periodic
i.e. apoc.periodic.truncate
Then it's slightly more obvious that normal transaction rules don't apply

[jexp]

actually it should just use the java API in parallel transactions. or perhaps kernel api.

db.getAllRelationships().stream().chunk().foreach(Relationship::delete);
db.getAllNodes().parallelStream().chunk().foreach(Node::delete);

But cypher would work too.
Nodes can be deleted in parallel, relationships is a bit more tricky.

to delete clusters concurrently it would be kinda cool to run a clustering algo first,
then delete the clusters innards in separate tx and at the end the boundary nodes and their rels sequentially.

[jexp]

periodically truncate the database :)

good for chaos monkey

[eastlondoner]

It would be a bonus if this had a configuration option to drop all indexes.