Question

我尝试使用py2neo航班模型化将包含22列的CSV文件（包含22个列）加载到neo4j图中。

密码查询在一个查询中使用，并包含节点（机场，城市，航班和飞机）之间的节点和关系创建。但是在运行代码时，即使使用PERICODIC COMMIT也需要永远。

我不确定我编写的密码查询是否已经过优化，可能是缓慢的来源。对于10 000行，我花了大约10分钟来构建图表... 有人可以帮我吗？这是代码：

def importFromCSVtoNeo(graph):
query = '''
    USING PERIODIC COMMIT 1000
    LOAD CSV WITH HEADERS FROM "file:///flights.csv" AS row FIELDTERMINATOR '\t' 
    WITH row 

    MERGE (c_departure:City {cityName: row.cityName_departure}) 
    MERGE (a_departure:Airport {airportName: row.airportName_departure}) 
    MERGE (f_segment1:Flight {airline: row.airline1}) 
    ON CREATE SET f_segment1.class = row.class1, 
                  f_segment1.outboundclassgroup = row.outboundclassgroup1 

    MERGE (a_departure)-[:IN]->(c_departure) 
    MERGE (c_departure)-[:HAS]->(a_departure) 
    MERGE (f_segment1)-[:FROM {departAt: row.outbounddeparttime}]->(a_departure) 

    MERGE (c_transfer:City {cityName: row.transferCityName}) 
    MERGE (a_transfer:Airport {airportName: row.airportName_transfer}) 
    MERGE (f_segment1)-[:TO_TRANSFER {transferArriveAt: row.transferArriveAt}]->(a_transfer) 
    MERGE (a_transfer)-[:IN]->(c_transfer) 
    MERGE (c_transfer)-[:HAS]->(a_transfer) 

    MERGE (c_arrival:City {cityName: row.cityName_arrival}) 
    MERGE (a_arrival:Airport {airportName: row.airportName_arrival}) 
    MERGE (f_segment2:Flight {airline: row.airline2}) 
    ON CREATE SET f_segment2.class = row.class2, 
                  f_segment2.outboundclassgroup = row.outboundclassgroup2 
    MERGE (f_segment2)-[:TO {arrivalAt: row.outboundarrivaltime}]->(a_arrival) 
    MERGE (f_segment2)-[:FROM_TRANSFER {transferDepartAt: row.transferDepartAt}]->(a_transfer) 
    MERGE (a_arrival)-[:IN]->(c_arrival) 
    MERGE (c_arrival)-[:HAS]->(a_arrival) 


    MERGE (p:Plane {saleprice: row.saleprice}) 
    ON CREATE SET p.depart = row.cityName_departure, 
                  p.destination = row.cityName_arrival, 
                  p.salechannel = row.salechannel, 
                  p.planeDuration = row.planeDuration 
    MERGE (p)-[:HAS_FLIGHTS]->(f_segment1) 
    MERGE (f_segment1)-[:WAIT_FOR {waitingTime: row.waitingTime}]->(f_segment2) 
    '''

graph.run(query)


if __name__ == '__main__':
    graph = Graph()
    importFromCSVtoNeo(graph)

我也尝试在批处理模式下进行，但性能并没有变得更好...... 我将不胜感激任何意见或建议。谢谢!!

Answer 1

我会在启动脚本之前在节点属性上使用索引，以便让neo4j在使用MERGE时使用它们进行快速查找（因为它必须逐行MATCH节点）。例如，对于我将使用的第一个节点属性：

CREATE INDEX ON :City(cityname)

等等。您可以在py2neo中直接将它们创建为单个运行语句。

Neo4j：使用py2neo

1 个答案: