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[英]How do I get all nodes that do not contain (relate) nodes with certain property in Cypher Neo4j
[英]How can I create relationships in neo4j/Cypher from a csv that depend on the type of nodes?
我正在嘗試將 csv 導入 Neo4j ,其中包含人、組織、銀行、資產等之間的關系,其中每行只有一個關系。 列名是FROM、A.Type、TO、B.type ,然后是不同的屬性。 在這里,from 和 to 標簽有名字,AB.type 表示它是否屬於一個人、組織等。
我設法根據FOREACH
的類型創建節點(大約 3500 個),如下所示:
FOREACH (_ IN CASE WHEN line.`A.type` = 'ASSET' THEN [1] ELSE [] END | MERGE (asset:Asset {Name:line.FROM}))
FOREACH (_ IN CASE WHEN line.`A.type` = 'BANK' THEN [1] ELSE [] END | MERGE (bank:Bank {Name: line.FROM}))
. . .
FOREACH (_ IN CASE WHEN line.`B.type` = 'ACTIVO' THEN [1] ELSE [] END | MERGE (asset:Asset {Name:line.TO}))
FOREACH (_ IN CASE WHEN line.`B.type` = 'BANCO' THEN [1] ELSE [] END | MERGE (bank:Bank {Name: line.TO}))
. . .
我現在的問題是創建每行的關系,我嘗試了許多不同的方法,但似乎沒有任何效果。 例如:
FOREACH
更改為兩個不同的節點,具體取決於它們是在 FROM 還是 TO 列上:WITH 'link' as line
LOAD CSV WITH HEADERS FROM url AS line
WITH line WHERE line.FROM = 'ASSET' AND line.TO = 'ORGANIZATION'
MERGE (a1:Asset {Name:line.FROM})
MERGE (o2:Organization {Name:line.TO})
CREATE (a1)-[con:PROPERTY_OF]->(o2)
FOREACH(n IN (CASE WHEN line.`A.type` = 'ASSET' THEN [1] ELSE [] END) | FOREACH(t IN CASE WHEN line.`B.type` = 'ORGANIZATION' THEN [1] ELSE [] END | MERGE (asset)-[ao:CONNECTED_WITH]->(organization)))
WITH asset, organization, line
CALL apoc.create.relationship(asset, line.RelationshipType, NULL, organization) YIELD rel
RETURN asset, rel, organization
以及每個的不同變體,從頭開始創建節點或匹配它們。 每次查詢似乎有效時,它都會運行,但它不會創建任何關系,或者它會在 csv 中不存在的新節點之間創建單一關系,沒有名稱或 label。
我對 Cypher/Neo4j 完全陌生,並且不知所措,如果有人能指出我的錯誤以及如何糾正它們,將不勝感激。
先感謝您!
A.type
和B.type
。MERGE
子句替換為MATCH
子句。MERGE
而不是CREATE
來創建關系。例如:
LOAD CSV WITH HEADERS FROM 'file:///' AS line
CALL apoc.do.case([
line.`A.type` = 'ASSET' AND line.`B.type` = 'ORGANIZATION',
'MATCH (a:Asset {Name: line.FROM}), (b:Organization {Name: line.TO}) MERGE (a)-[:FOO]->(b) RETURN a, b',
line.`A.type` = 'ASSET' AND line.`B.type` = 'BANCO',
'MATCH (a:Asset {Name: line.FROM}), (b:Bank {Name: line.TO}) MERGE (a)-[:FOO]->(b) RETURN a, b',
line.`A.type` = 'BANK' AND line.`B.type` = 'ACTIVO',
'MATCH (a:Bank {Name: line.FROM}), (b:Asset {Name: line.TO}) MERGE (a)-[:FOO]->(b) RETURN a, b'
],
'', // empty ELSE case
{line: line}
) YIELD value
RETURN value
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