Cypher stats

[stefanli]

More of a feature request than a bug.

Currently if you do a MATCH and SET without a RETURN statement in a cypher query it is not possible to know whether the SET was successful or not (e.g. due to a failed match). The REST API has a "stats" field that contains this information e.g:

{
"results": [{
"columns": [],
"data": [],
"stats": {
"contains_updates": true,
"nodes_created": 1,
"nodes_deleted": 0,
"properties_set": 1,
"relationships_created": 0,
"relationship_deleted": 0,
"labels_added": 1,
"labels_removed": 0,
"indexes_added": 0,
"indexes_removed": 0,
"constraints_added": 0,
"constraints_removed": 0
}
}],
"errors": []
}

But this is never exposed in the GraphDatabase.cypher() callback. The only workaround right now that I know of is to add a RETURN statement which adds an unnecessary penalty hit.

[aseemk]

Nice idea! I was only vaguely aware of stats, but haven't experienced it myself. How do you get it?

[aseemk]

Btw, FWIW, we at @fiftythree do RETURN in order to get this info, but it doesn't have to be a penalty hit: you can always RETURN COUNT(foo), which is usually the same info as the stat you're interested in.

E.g. unfollow and return whether unfollowed (or wasn't following in the first place):

MATCH (a:User ...) -[r:follows]-> (b:User ...)
DELETE r
RETURN COUNT(r)

That returns 1 if a relationship was found and deleted, 0 if not.

[sagdelen]

It would be very nice to have this kind of stats optionally.