Titan 和 Cassandra 在保留图形时截断长字符串

Question

创建图表时，例如：

TitanGraph graph =  TitanFactory.open("conf/titan-cassandra-es.properties");
Vertex v = graph.addVertex()
v.property("Value", "very very very very very very very very vey long string");
graph.tx().commit();

我发现 titan 在提交时将字符串截断为仅 20 个字符。我正在使用 here 定义的标准配置。是否缺少一些其他配置？

Answer 1

您看到的是您得到的是 VertexProperty.toString() 的结果，而不是 VertexProperty.value() 的值。这是一个 Gremlin 控制台会话来演示差异：

gremlin> graph = TitanFactory.build().set('storage.backend','cassandra').set('storage.cassandra.keyspace','fido').open()
==>standardtitangraph[cassandra:[127.0.0.1]]
gremlin> v = graph.addVertex() // create a vertex
==>v[4256]
gremlin> v.property('value', 'very very very very very very very very vey long string') // set a property
==>vp[value->very very very very ]
gremlin> v.property('value').getClass() // check the class on the property
==>class com.thinkaurelius.titan.graphdb.relations.StandardVertexProperty
gremlin> v.property('value').toString() // vertex property object as a string
==>vp[value->very very very very ]
gremlin> v.property('value').value().getClass() // check the class of the value of the vertex property
==>class java.lang.String
gremlin> v.property('value').value() // get the value of the vertex property (explicit syntax)
==>very very very very very very very very vey long string
gremlin> v.values('value').next().getClass() // check the class of the value of the vertex property
==>class java.lang.String
gremlin> v.values('value').next() // get the value of the vertex property (simpler syntax)
==>very very very very very very very very vey long string

在 TinkerPop3 文档中有一些关于 vertex properties 值得一读的讨论。

Titan 和 Cassandra 在保留图形时截断长字符串

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