Question

为了创建节点，我编写了3个查询：对节点的属性以及与节点：Users和：Posts的关系进行注释：

USING PERIODIC COMMIT 10000
LOAD CSV WITH HEADERS FROM "http://neuromancer.inf.um.es:8080/es.stackoverflow/Comments.csv" AS row
    CREATE(n)
    SET n=row
    WITH n AS node
        CREATE (c:Comment {Id: node.Id, CreationDate: node.CreationDate,
                           Score: node.Score, Text: node.Text,
                           UserId: node.UserId, PostId: node.PostId});

MATCH (c:Comment), (u:User)
WHERE toInt(c.UserId) = toInt(u.Id)
    CREATE (u)-[:AUTHOR_OF]->(c)
    REMOVE c.UserId;

MATCH (c:Comment), (p:Post)
WHERE toInt(c.PostId) = toInt(p.Id)
    CREATE (c)-[:INCLUDED_IN]->(p)
    REMOVE c.PostId;

第一个查询创建节点，第二个和第三个查询创建：Comment和：User和：Comment和：Post之间的关系。但是，我想创建一个查询来创建所有这些查询，以使其效率更高。这可行吗，我该怎么做？我找不到办法。

Answer 1

首先，不需要创建临时节点n或临时id属性。其次，根据文件的大小，对文件进行两次传递可能更有效，一次传递来创建注释，第二次传递来匹配节点并创建关系。最好尝试/配置并查看。

只有一遍，这就是它的样子：

USING PERIODIC COMMIT 10000
LOAD CSV WITH HEADERS FROM "http://neuromancer.inf.um.es:8080/es.stackoverflow/Comments.csv" AS row
CREATE (c:Comment {Id: row.Id, CreationDate: row.CreationDate,Score: row.Score, Text: row.Text})
WITH c
MATCH (u:User) WHERE u.Id = toInt(row.UserId)
CREATE (u)-[:AUTHOR_OF]->(c)
WITH c
MATCH (p:Post) WHERE p.Id=toInt(c.PostId)
CREATE (c)-[:INCLUDED_IN]->(p)

两次通过

USING PERIODIC COMMIT 10000
LOAD CSV WITH HEADERS FROM "http://neuromancer.inf.um.es:8080/es.stackoverflow/Comments.csv" AS row
CREATE (c:Comment {Id: row.Id, CreationDate: row.CreationDate,Score: row.Score, Text: row.Text})

USING PERIODIC COMMIT 10000
LOAD CSV WITH HEADERS FROM "http://neuromancer.inf.um.es:8080/es.stackoverflow/Comments.csv" AS row
MATCH (c:Comment {Id: row.Id})
MATCH (u:User) WHERE u.Id = toInt(row.UserId)
MATCH (p:Post) WHERE p.Id=toInt(c.PostId)
CREATE (u)-[:AUTHOR_OF]->(c)
CREATE (c)-[:INCLUDED_IN]->(p)

从CSV加载时如何创建节点，创建关系并删除属性？

1 个答案: