anchor.diff:  * Manipulating indices with link:http://docs.neo4j.org/chunked/stable/query-schema-index.html[Cypher].
   * Manipulating indices with the Neo4j link:http://docs.neo4j.org/chunked/stable/tutorials-java-embedded-new-index.html[Java API].
   
  -[source,groovy]
  -gremlin> graph = Neo4jGraph.open('/tmp/neo4j')
  -==>neo4jgraph[EmbeddedGraphDatabase [/tmp/neo4j]]
  -gremlin> graph.cypher('CREATE INDEX ON :person(name)')
  -gremlin> graph.tx().commit() // schema mutations must happen in a different tx than graph mutations
  -==>null
  -gremlin> graph.addVertex(label,'person','name','marko')
  -==>v[0]
  -gremlin> graph.addVertex(label,'dog','name','puppy')
  -==>v[1]
  -gremlin> g = graph.traversal(standard())
  -==>graphtraversalsource[neo4jgraph[EmbeddedGraphDatabase [/tmp/neo4j]], standard]
  -gremlin> g.V().hasLabel('person').has('name','marko').values('name')
  -==>marko
  -
   [gremlin-groovy]
   ----
   graph = Neo4jGraph.open('/tmp/neo4j')
  
positive.code: 
  NeoTechnology are the creators of the graph pattern-match query language link:http://www.neo4j.org/learn/cypher[Cypher]. It is possible to leverage Cypher from within Gremlin by using the `Neo4jGraph.cypher()` graph traversal method.
  
  [source,groovy]
  gremlin> graph = Neo4jGraph.open('/tmp/neo4j')
  ==>neo4jgraph[EmbeddedGraphDatabase [/tmp/neo4j]]
  gremlin> graph.io(gryo()).readGraph('data/tinkerpop-modern.kryo')
  ==>null
  gremlin> graph.cypher('MATCH (a {name:"marko"}) RETURN a')
  ==>[a:v[0]]
  gremlin> graph.cypher('MATCH (a {name:"marko"}) RETURN a').select('a').out('knows').values('name')
  ==>vadas
  ==>josh
  
  Thus, like <<match-step,`match()`>>-step in Gremlin, it is possible to do a declarative pattern match and then move back into imperative Gremlin.
  
  
negative.code: <1> schema mutations must happen in a different tx than graph mutations
  
  Below demonstrates the runtime benefits of indices and demonstrates how if there is no defined index (only vertex labels), a linear scan of the vertex-label partition is still faster than a linear scan of all vertices.
  
  [gremlin-groovy]
  ----
  