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As of this moment, the openCypher support is a preview, not quite GA level. The more recent engine versions do have some significant improvements, but more are yet to be delivered.
As to the Gremlin query, tools that convert Cypher to Gremlin tend to build quite complex queries. I think the Gremlin equivalent to the Cypher query is going to look something like this.
g.V().has('Member','address', address).as('m'). out('HAS').hasLabel('Token').as('t'). in('HAS').hasLabel('Member').as('om'). where(neq('m')). group(). by('om'). by(select('t').count()). order(local). by(values,desc). limit(20)
and if you want all of the properties just add a valueMap as in:
g.V().has('Member','address', address).as('m'). out('HAS').hasLabel('Token').as('t'). in('HAS').hasLabel('Member').as('om'). where(neq('m')). group(). by(select('om').valueMap(true)). by(select('t').count()). order(local). by(values,desc). limit(20)
answered 2 years ago
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It may be beneficial to understand what sort of problem you're trying to solve to see if Neptune can optimally handle it. Can you provide an example graph structure and similar query that is giving you issues?
F. e., we have
MemberandTokennodes and there is aHASrelation between them. We need to find the top 20 other members who have the same tokens as the specific member.MATCH (member:Member { address: '${address}' })-[:HAS]->(token:Token)<-[:HAS]-(other_member:Member) RETURN PROPERTIES(other_member) as member, COUNT(token) AS number_of_tokens ORDER BY number_of_tokens DESC LIMIT 20This query in AuraDB takes milliseconds but seconds on Neptune. The same Gremlin query is faster than OpenCypher but still slower than in AuraDB. We also have many complex queries where the difference is much more significant.
Here is also the same query using Gremlin:
g.V().hasLabel('Member').has('address', eq('${address}')).outE('HAS').as('member_has').inV().as('token').hasLabel('Token').inE('HAS').as('other_member_has').outV().as('other_member').hasLabel('Member').where(__.select('member_has').where(neq('other_member_has'))).select('other_member', 'token').group().by(__.select('other_member').local(__.properties().group().by(__.key()).by(__.map(__.value())))).by(__.fold().project('member', 'number_of_tokens').by(__.unfold().select('other_member').choose(neq('cypher.null'), __.local(__.properties().group().by(__.key()).by(__.map(__.value()))))).by(__.unfold().select('token').count())).unfold().select(values).order().by(__.select('number_of_tokens'), desc).limit(20)