创建唯一时，Cypher foreach似乎不会遍历集合 [英] Cypher foreach does not appear to iterate over collection when creating unique

问题描述

对于以下查询:

START n=node(1) 
MATCH (n)-[:KNOWS]->(k), (n)-[:LOVES]->(l)
WITH collect(k) + collect(l) as friends, n
FOREACH(f in friends : create unique (n)-[:FRIEND]->(f))

(数据与console.neo4j.org相同) 我希望朋友是Morpheus和Trinity，所以从Neo到Morpheus和Neo到Trinity建立了新的FRIEND关系. 但是，在执行查询时，只会创建一个关系(Neo-[:FRIEND]-> Morpheus). 再次执行查询，并创建另一个关系(Neo-[:FRIEND]-> Trinity)

(Data is as on console.neo4j.org) I expect that friends are Morpheus and Trinity so a new FRIEND relation is created from Neo to Morpheus and Neo to Trinity. However, on executing the query, there is only one relation created (Neo-[:FRIEND]->Morpheus). Execute the query again and the other relation is created (Neo-[:FRIEND]->Trinity)

那是为什么? (使用Neo4j 1.8.2)

Why is that? (Using Neo4j 1.8.2)

推荐答案

我今天在变更日志中注意到这是一个错误，并且已在最新的1.9.M05版本中修复. Fixes #489 - CREATE UNIQUE does not work as expected inside FOREACH

i noticed today in the changelog that this was a bug and has been fixed in the newest 1.9.M05 version. Fixes #489 - CREATE UNIQUE does not work as expected inside FOREACH

更多信息，请参见 https://github.com/neo4j/neo4j/blob/master/packaging/standalone/standalone-enterprise/src/main/distribution/text/enterprise/CHANGES.txt

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