How to find the cardinality of property in apache tinkerpop Gremlin?
Is there any method to find the given property cardinality is SET
or SINGLE
?
Some database implementations allow you to set and query a schema, but Apache TinkerPop/Gremlin currently does not have a schema API. Further, the cardinality of a property value is not stored explicitly as something you can query.
The set
and single
cardinality keywords are only really used when properties are changed/created. They tell the query engine whether to replace the value, or add it in a set fashion.
Once added, Gremlin does not provide an explicit way to ask "is this property value part of a set?".
However, you can always count
to find out. If the count is greater than one then you have a set or a list.
gremlin> g.addV('test').property('myset',1)
==>v[61407]
gremlin> g.V(61407).property(set,'myset',2)
==>v[61407]
gremlin> g.V(61407).values('myset').count()
==>2