在Neo4j Cypher Query中的FOREACH之后无法返回节点

Question

We are creating a time tree, and this query here works:

CREATE (c:Century {century_label: 2000})
MATCH (c:Century {century_label: 2000})
WITH range(1900,1905) as YEARS, c
FOREACH (year in YEARS | CREATE (y:Year {year_label:year})-[r:YEAR_IN]->(c))

This one doesn't:

CREATE (c:Century {century_label: 2000})
MATCH (c:Century {century_label: 2000})
WITH range(1900,1905) as YEARS, c
FOREACH (year in YEARS | CREATE (y:Year {year_label:year})-[r:YEAR_IN]->(c))
RETURN y as YEAR

The problem is the y as YEAR , Neo4j throws an error about y , so it seems that you cannot do FOREACH and then collect the results after.

What is the proper syntax to return all the created nodes?

Answer 1

I got the answer from the Neo4j Slack:

MATCH (c:Century {century_label:$century})
UNWIND range(1900,1999) as year
CREATE (y:Year {year_label:year})-[r:YEAR_IN]->(c)
RETURN y AS YEAR

Based on my reading as well, I believe this UNWIND is the successor to some of these more antiquated queries. I highly recommend gravitating towards unwind as much as possible.

We see the best performance with it in all tested cases so far.