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Neo4j急切和可选匹配问题_Neo4j_Eager Loading - Fatal编程技术网

Neo4j急切和可选匹配问题

Neo4j急切和可选匹配问题,neo4j,eager-loading,Neo4j,Eager Loading,当我尝试执行以下查询(创建教师和学生之间的关系)时,我在配置文件中看到一个急切的弹出窗口: USING PERIODIC COMMIT 10000 LOAD CSV WITH HEADERS FROM "file:/AFile" as line WITH line MATCH (teacher:Teacher {ValueOne: toInt(line.ValueOne)}) MATCH (bully:Bully { Value2:toInt(line.ValueTwo)}) MATCH (bu

当我尝试执行以下查询(创建教师和学生之间的关系)时,我在配置文件中看到一个急切的弹出窗口:

USING PERIODIC COMMIT 10000
LOAD CSV WITH HEADERS FROM "file:/AFile" as line
WITH line
MATCH (teacher:Teacher {ValueOne: toInt(line.ValueOne)})
MATCH (bully:Bully { Value2:toInt(line.ValueTwo)})
MATCH (bully)-[:LOVES]->(student:Student)
CREATE (student)<-[:HELPS]-(teacher)
;
这导致了以下错误:

另一个节点为空

我还试图限制学生匹配只返回一个学生,但这也不起作用。然而,我认为我做得不对,我加上了学生限制1

有没有人对如何减少渴望的数量提出建议?如果没有最后的创作,我就不会有渴望,我也会有渴望

按照Stefan的建议,我不再得到一个渴望,而是得到了“Other node is null”错误

  • 空结果
  • 更新图
  • 选配
  • SchemaIndex(0)
  • 方案索引(1)
  • 切片
  • 柱形过滤器
  • 过滤器(0)
  • 提取
  • LoadCSV
  • 过滤器(1)
  • SimplePatternMatcher
  • 论据

至少在2.2.2中,以下内容似乎没有渴望的

USING PERIODIC COMMIT 10000
LOAD CSV WITH HEADERS FROM "file:/AFile" as line
WITH line
MATCH (teacher:Teacher {ValueOne: toInt(line.ValueOne)})
MATCH (bully:Bully { Value2:toInt(line.ValueTwo)})
OPTIONAL MATCH (bully)-[:LOVES]->(student)
WHERE student IS NOT NULL and "Student" in labels(student)
MERGE (student)<-[:HELPS]-(teacher)
使用周期提交10000
将“文件:/a文件”中的标题作为行加载CSV
用线
匹配(教师:教师{ValueOne:toInt(line.ValueOne)})
匹配(bully:bully{Value2:toInt(line.ValueTwo)})
可选匹配(欺负)-[:爱]->(学生)
其中student不为NULL且标签中为“student”(学生)

合并(学生)当我使用可选匹配时,即使没有在
可选匹配中指定标签,我仍然遇到“其他节点为空”
?是的,不幸的是,情况就是这样。你能提供当前数据库(也称为graph.db文件夹)和csv的前100行吗?
USING PERIODIC COMMIT 10000
LOAD CSV WITH HEADERS FROM "file:/AFile" as line
WITH line
MATCH (teacher:Teacher {ValueOne: toInt(line.ValueOne)})
MATCH (bully:Bully { Value2:toInt(line.ValueTwo)})
OPTIONAL MATCH (bully)-[:LOVES]->(student)
WHERE student IS NOT NULL and "Student" in labels(student)
MERGE (student)<-[:HELPS]-(teacher)