Neo4J和密码查询

Question

我是Neo4j和Cypher的新手，query.My创建查询就像每个商店有2台冷冻机，每台有2台PLC，而每台PLC又有2个传感器。

创建如下所示

Create(:SHOP{name:"Shop1"})-[:hasChiller]->(:CHILLER{name:"Chiller1"})
Create(:SHOP{name:"Shop1"})-[:hasChiller]->(:CHILLER{name:"Chiller2"})

Create(:SHOP{name:"Shop2"})-[:hasChiller]->(:CHILLER{name:"Chiller3"})
Create(:SHOP{name:"Shop2"})-[:hasChiller]->(:CHILLER{name:"Chiller4"})

Create(:CHILLER{name:"Chiller1"})-[:hasPLC]->(:PLC{name:"Plc1"})
Create(:CHILLER{name:"Chiller1"})-[:hasPLC]->(:PLC{name:"Plc2"})

Create(:CHILLER{name:"Chiller2"})-[:hasPLC]->(:PLC{name:"Plc3"})
Create(:CHILLER{name:"Chiller2"})-[:hasPLC]->(:PLC{name:"Plc4"})

Create(:CHILLER{name:"Chiller3"})-[:hasPLC]->(:PLC{name:"Plc5"})
Create(:CHILLER{name:"Chiller3"})-[:hasPLC]->(:PLC{name:"Plc6"})

Create(:CHILLER{name:"Chiller4"})-[:hasPLC]->(:PLC{name:"Plc7"})
Create(:CHILLER{name:"Chiller4"})-[:hasPLC]->(:PLC{name:"Plc8"})

Create(:PLC{name:"Plc1"})-[:hasSensor]->(:SENSOR{name:"Sensor1"})
Create(:PLC{name:"Plc1"})-[:hasSensor]->(:SENSOR{name:"Sensor2"})
Create(:PLC{name:"Plc2"})-[:hasSensor]->(:SENSOR{name:"Sensor3"})
Create(:PLC{name:"Plc2"})-[:hasSensor]->(:SENSOR{name:"Sensor4"})
Create(:PLC{name:"Plc3"})-[:hasSensor]->(:SENSOR{name:"Sensor5"})
Create(:PLC{name:"Plc3"})-[:hasSensor]->(:SENSOR{name:"Sensor6"})
Create(:PLC{name:"Plc4"})-[:hasSensor]->(:SENSOR{name:"Sensor7"})
Create(:PLC{name:"Plc4"})-[:hasSensor]->(:SENSOR{name:"Sensor8"})
Create(:PLC{name:"Plc5"})-[:hasSensor]->(:SENSOR{name:"Sensor9"})
Create(:PLC{name:"Plc5"})-[:hasSensor]->(:SENSOR{name:"Sensor10"})
Create(:PLC{name:"Plc6"})-[:hasSensor]->(:SENSOR{name:"Sensor11"})
Create(:PLC{name:"Plc6"})-[:hasSensor]->(:SENSOR{name:"Sensor12"})
Create(:PLC{name:"Plc7"})-[:hasSensor]->(:SENSOR{name:"Sensor13"})
Create(:PLC{name:"Plc7"})-[:hasSensor]->(:SENSOR{name:"Sensor14"})
Create(:PLC{name:"Plc8"})-[:hasSensor]->(:SENSOR{name:"Sensor15"})
Create(:PLC{name:"Plc8"})-[:hasSensor]->(:SENSOR{name:"Sensor16"})

然而，在SHOP1下获得传感器的匹配

MATCH(s:SHOP{name:"Shop1"})-[:hasChiller]->(cc:CHILLER)-[:hasPLC]->(pp:PLC)-[:hasSensor]->(ss:SENSOR) return ss.name

返回nothing.Says，无更改且无数据。

我正在Neo4J沙箱环境中尝试这一点，我是基于我在SQL SERVER GRAPH 2019中使用match子句的理解来实现这一点的。

有谁能指出我哪里错了吗？

Answer 1

您错误地创建了“相同”节点的多个实例。您应该创建每个节点一次，然后在以后需要创建涉及该节点的关系时使用它的绑定变量名。

删除您的所有数据，并遵循此模式(您必须填写"...“部件)：

CREATE
  (sh1:SHOP{name:"Shop1"}), (sh2:SHOP{name:"Shop1"}),
  (c1:CHILLER{name:"Chiller1"}), (c2:CHILLER{name:"Chiller2"}),(c3:CHILLER{name:"Chiller3"}), (c4:CHILLER{name:"Chiller4"}),
  (p1:PLC{name:"Plc1"}), ..., (p8:PLC{name:"Plc8"}),
  (se1:SENSOR{name:"Sensor1"}), ..., (se16:SENSOR{name:"Sensor16"}),

  (sh1)-[:hasChiller]->(c1), (sh1)-[:hasChiller]->(c2),
  ... // create remaining relationships using bound variable names for nodes