如何從路徑中提取標籤？

Question

我有查詢

MATCH (rootPerson:Person {uuid: '650wer0a-2374-11e6-aabd-ce6wqe3145e4'}) 
MATCH (mother:Rerson)<-[rel:MOTHER*0..4]-(rootPerson) 
WITH mother 
SKIP 1 
MATCH (children:Person)-[:MOTHER]->(mother) 
MATCH (grand_children:Person)-[:FATHER|:MOTHER]->(children) 
OPTIONAL MATCH (grand_children)-[:STUDY_AT]->(uni:University)... 

而問題是，Neo4j的匹配不只是grand_children但孩子和家長的歡迎，並它的速度非常慢下來，並返回了很多useles額外的數據，我該怎麼做配套只有grand_children？

Answer 1

因爲您不必要地使用可變長度路徑模式（通過*0..4語法），所以您獲得grand_children多代。

這應該正常工作：

MATCH (rootPerson:Person {uuid: '650wer0a-2374-11e6-aabd-ce6wqe3145e4'}) 
MATCH (rootPerson)-[:MOTHER]->(mother:Person) 
MATCH (children:Person)-[:MOTHER]->(mother:Person) 
MATCH (grand_children:Person)-[:FATHER|:MOTHER]->(children) 
OPTIONAL MATCH (grand_children)-[:STUDY_AT]->(uni:University) 
...