由gds.alpha.kShortestPaths.stream

如何解决由gds.alpha.kShortestPaths.stream

我使用Neo4j 4.0.2运行gds.alpha.kShortestPaths.stream。该算法产生一条路径。 该路径具有以NEXT关系连接的节点。我需要在图中找到连接路径中节点的实际关系。我根据知道的路径长度提出了一个混乱的查询：

...
YIELD path
with nodes(path) as nodes with nodes[0] as n0,nodes[1] as n1,nodes[2] as n2,nodes[3] as n3
match (n0)-[r1]-(n1)
match (n1)-[r2]-(n2)
match (n2)-[r3]-(n3)
return n0,n1,n2,n3,r1,r2,r3

显然，该解决方案是不够的，我在此处发布此解决方案的唯一原因是为了说明我对任何长度的路径都需要执行的操作。

谢谢

解决方法

您可以通过以下方式以编程方式执行此操作：

YIELD index,path
WITH index,nodes(path) as nodes
WITH index,nodes,size(nodes) as number_of_nodes
UNWIND range(0,number_of_nodes - 2) as start
WITH index,nodes[start] as start_node,nodes[start + 1] as end_node
MATCH (start_node)-[r:NEXT]->(end_node)
RETURN index,start_node,r,end_node