neo4j条件中的语法无效

Question

如果节点没有关系并返回true，我想删除节点，否则返回false

match (p:Type {id:72})-->(x)
RETURN 
CASE count(x)
WHEN 0 THEN DELETE p 'true'
ELSE 'false'
END AS deleted;

我总是得到无效的语法。这在密码中是否可行？

Answer 1

或者

match (p:Type {id:72})
where not exists ((p)--())
delete p

Answer 2

要查找没有关系的节点，您需要使用OPTIONAL MATCH并在WITH之后检查空值：

match (p:Type {id:72})
optional match (p)-[r]-()
with p, r
where r IS null
delete p