我有以下简单的图表:
http://console.neo4j.org/?id=v0cvwn
我想知道为什么会出现以下查询:
START n=node(2)
match n-[:KNOWS]-node
return node.name as name
UNION
START n=node(2)
match n-[:ACTS_IN]-node
return node.name as name
抛出异常:
java.lang.AssertionError: assertion failed: Can't profile the same pipe twice
at scala.Predef$.assert(Predef.scala:179)
at org.neo4j.cypher.internal.profiler.Profiler.decorate(Profiler.scala:47)
at org.neo4j.cypher.internal.pipes.Pipe$class.createResults(Pipe.scala:35)
at org.neo4j.cypher.internal.pipes.NullPipe$.createResults(Pipe.scala:47)
at org.neo4j.cypher.internal.pipes.PipeWithSource.createResults(Pipe.scala:61)
at org.neo4j.cypher.internal.pipes.PipeWithSource.createResults(Pipe.scala:61)
at org.neo4j.cypher.internal.pipes.PipeWithSource.createResults(Pipe.scala:61)
at org.neo4j.cypher.internal.pipes.UnionIterator.loadNextIterator$1(UnionIterator.scala:60)
at org.neo4j.cypher.internal.pipes.UnionIterator.step$1(UnionIterator.scala:68)
at org.neo4j.cypher.internal.pipes.UnionIterator.stepIfNeccessary(UnionIterato
关于 UNION 的几个问题:
是否可以对之前子查询中 UNION 的结果集中累积在结果集中的所有数据执行另一个最终匹配子句？
是否可以根据该数据执行订单？
谢谢。
最佳答案
根据这些 github 评论，UNION 仅在 2.0 或更高版本中支持。
关于neo4j - 密码 UNION 查询，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/16018607/