Question

在v2.0.3中运行的查询

START n = NODE(67635)   
MATCH (n:publication)   
WHERE n.status <> 0 
OPTIONAL MATCH (n)-[re:contains|can_use]->(e)   
WHERE (e:article) AND (e.status <> 0 AND re.status <> 0)    
WITH n, e   
ORDER BY e.created DESC 
WITH n, COLLECT(e) AS ce    
RETURN n, ce[0..10], LENGTH(ce)

现在，在v2.1.2中，我得到以下错误：

Cannot match on a pattern containing only already bound identifiers (line 2, column 1)\n\"MATCH (n:publication)\"\n ^\n    [exception] => SyntaxException\n    [fullname] => org.neo4j.cypher.SyntaxException\n    [stacktrace] => Array\n        (\n            [0] => org.neo4j.cypher.internal.compiler.v2_1.SemanticChecker$$anonfun$check$1.apply(SemanticChecker.scala:40)\n            [1] => org.neo4j.cypher.internal.compiler.v2_1.SemanticChecker$$anonfun$check$1.apply(SemanticChecker.scala:40)\n

我知道如何修复它，但如果可能的话，我想避免在整个项目中修复查询。还有其他解决办法吗？

Answer 1

您可以将Neo4j数据库配置为使用较旧的Cypher编译器/解析器，例如： CYPHER 2.0

您可以针对每个查询执行此操作，也可以在neo4j.properties

中全局执行该操作

cypher_parser_version=CYPHER 2.0

Answer 2

将此重构为：

MATCH (n:publication)   
WHERE ID(n)=67635 AND n.status <> 0 
OPTIONAL MATCH (n)-[re:contains|can_use]->(e)   
WHERE (e:article) AND (e.status <> 0 AND re.status <> 0)    
WITH n, e   
ORDER BY e.created DESC 
WITH n, COLLECT(e) AS ce    
RETURN n, ce[0..10], LENGTH(ce)

另请注意，匹配多种关系类型现在需要使用冒号作为每种类型的前缀：

old: OPTIONAL MATCH (n)-[re:contains|can_use]->(e)   
new: OPTIONAL MATCH (n)-[re:contains|:can_use]->(e)

升级到Neo4j v2.1.2后，Cypher查询无效

2 个答案: