Neo4j csv 數據攝取節點正在復制

Question

我正在嘗試將 csv 文件攝取到 neo4j 中。 我能夠正確添加屬性，但是當我創建關系時，節點會被復制。 我正在使用的 cypher 查詢

LOAD CSV WITH HEADERS FROM "file:///column_meta.csv" AS csv
CREATE (a:db { db_name: csv.table_schema})
CREATE (b:table {table_name: csv.table_name})
CREATE (c:column {col_name: csv.col_name, col_desc:csv.col_comment})

MERGE (a)<-[:belongs_to]-(b)
MERGE (b)<-[:has]-(c)

這里正在創建節點和關系，但它們中的每一個都是分開的，而我正在考慮創建相互依賴的關系，例如 db_name->table_name->col_name。 誰能指出我做錯了什么？

Answer 1

嘗試這個：

MERGE可以在全局（有約束）或現有節點的上下文中唯一地創建數據

LOAD CSV WITH HEADERS FROM "file:///column_meta.csv" AS csv
MERGE (a:db { db_name: csv.table_schema})
MERGE (a)<-[:belongs_to]-(b:table {table_name: csv.table_name})
MERGE (b)<-[:has]-(c:column {col_name: csv.col_name})
ON CREATE SET c.col_desc=csv.col_comment

確保在:db(db_name)上創建約束並在:table(table_name)和:column(col_Name)上創建索引

Answer 2

試試這個例子：

--Load Order
LOAD CSV WITH HEADERS FROM 'file:///TestFolder//Order.csv' AS line
WITH line
Merge(O:OrderInformation{name:line.orderID,orderID:line.orderID})
Return Count(*);

--Load Customer
LOAD CSV WITH HEADERS FROM 'file:///TestFolder//Customer.csv' AS line
WITH line
Merge(C:Customer{name:line.customerName,customerID:line.customerID,customerName:line.customerName})
Return Count(*);

--Load Order and Customer Relationship
LOAD CSV WITH HEADERS FROM 'file:///TestFolder//Order.csv' AS row
WITH row
MATCH (O:OrderInformation {name:row.orderID}), (C:Customer {customerID:row.customerID})
//now create a relationship between them
CREATE (C)-[:ORDERS]->(O);

希望能幫助到你！

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