neo4j服务器版本安装相应的算法库并使用

Posted 2021-10-24 Coding With you.....

安装

1.在https://github.com/neo4j-contrib/neo4j-graph-algorithms/releases下载匹配版本的插件graph-algorithms-algo-[version].jar ，下载后放到$NEO4J_HOME/plugins目录下。

版本可以在https://github.com/neo4j-contrib/neo4j-graph-algorithms/blob/master/versions.json查看

2.将dbms.security.procedures.unrestricted=algo.* 这句话添加到$NEO4J_HOME/conf/neo4j.conf文件中,需要为库提供不受限制的访问权限，因为算法使用较低级别的内核API来读取和写入。

3.重启neo4j并输入CALL algo.list() 验证是否安装成功，出现下图则表明安装成功

使用

通过Cypher语句就可以执行

eg:

数据：

MERGE (home:Page {name:'Home'}) MERGE (about:Page {name:'About'}) MERGE (product:Page {name:'Product'}) MERGE (links:Page {name:'Links'}) MERGE (a:Page {name:'Site A'}) MERGE (b:Page {name:'Site B'}) MERGE (c:Page {name:'Site C'}) MERGE (d:Page {name:'Site D'})   MERGE (home)-[:LINKS]->(about) MERGE (about)-[:LINKS]->(home) MERGE (product)-[:LINKS]->(home) MERGE (home)-[:LINKS]->(product) MERGE (links)-[:LINKS]->(home) MERGE (home)-[:LINKS]->(links) MERGE (links)-[:LINKS]->(a) MERGE (a)-[:LINKS]->(home) MERGE (links)-[:LINKS]->(b) MERGE (b)-[:LINKS]->(home) MERGE (links)-[:LINKS]->(c) MERGE (c)-[:LINKS]->(home) MERGE (links)-[:LINKS]->(d) MERGE (d)-[:LINKS]->(home)

代码：

CALL algo.pageRank.stream('Page', 'LINKS', {iterations:20, dampingFactor:0.85})
YIELD nodeId, score
 
RETURN algo.asNode(nodeId).name AS page,score
ORDER BY score DESC