Neo4j tips

How to get nodes without labels ?

To get nodes which don't have label specified, we can use this Cypher query: MATCH n WHERE LENGTH(LABELS(n)) = 0 RETURN n ...

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How to set label in Cypher ?

Labels, as other node properties, can be defined with SET clause. This query should add label "Animal" to label only with "Cat": CREATE (c:Cat); MATCH (c:Cat) SET c :Animal RETURN LABELS(c) /...

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How to execute file from Neo4j shell ?

Without starting new shell session, we can do that with this command: bartosz@home:~/dev/NEO4J_HOME$ ./bin/neo4j-shell -file cypher_queries_to_execute.cql ...

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How to backup database on the fly ?

Normally we can backup Neo4j database by stopping it, archiving graph.db (or another pointed by org.neo4j.server.database.location attribute), and restarting Neo4j. But another, simpler possibility, i...

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How execute Cypher queries from file ?

To achieve this task Neo4j shell can be used. Imagine that you want to import following file: CREATE (:Somebody); MATCH (s:Somebody) CREATE (s)-[:LIVE]->(:Europe); To execute these 2 querie...

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How to activate debug mode ?

Because Neo4j launches separate JVM, debug mode can be configures as for other Java programs, in command line. All additionnal Neo4j JVM options are defined in neo4j-wrapper.conf file. The values need...

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