Question

我想知道是否有人可以帮助我理解Create Unique在Neo4J中的实际效果。我正在尝试将多个地址注册到托运人节点，我希望城市，州和国家/地区在地址中相同，以便它们都指向同一个节点。但问题是Create Unique导致数据库中存在多个相同节点的实例。

这是我必须向托运人注册地址的功能，我使用相同的托运人节点多次调用该地址，但指向同一城市的地址不同。

public Node<Address> RegisterShipperAddress(Node<Shipper> shipper,AddressType addressType ,Address address, City city, State state, Country country)
    {
        var shipperRef = shipper.Reference;
        var addressRef = neo4jClient.Cypher.Start(new { shipperNode = shipperRef }).CreateUnique("(shipperNode)-[r:HAS_ADDRESS { TypeName:{TypeName} }]->(addressRef{address})").WithParam("TypeName", addressType.TypeName).WithParam("address", address).Return<Node<Address>>("addressRef").Results.FirstOrDefault();
        var cityRef = neo4jClient.Cypher.Start(new { addressNode = addressRef }).CreateUnique("(addressNode)-[:BELONGS_TO_CITY]->(cityRef{cityData})").WithParam("cityData", city).Return<Node<City>>("cityRef").Results.FirstOrDefault();
        var stateRef = neo4jClient.Cypher.Start(new { cityNode = cityRef }).CreateUnique("(cityNode)-[:BELONGS_TO_STATE]->(stateRef{stateData})").WithParam("stateData", state).Return<Node<State>>("stateRef").Results.FirstOrDefault();
        var countryRef = neo4jClient.Cypher.Start(new { stateNode = stateRef }).CreateUnique("(stateNode)-[:BELONGS_TO_COUNTRY]->(countryRef{stateData})").WithParam("stateData", state).Return<Node<Country>>("countryRef").Results.FirstOrDefault();
        return addressRef;
    }

现在假设我用不同的地址调用上面的方法如下：

// First Call ....

RegisterShipperAddress(shipperNode,
                new AddressType { TypeName = "REGISTRED" },
                new Address
                {
                    Address1 = "151/1 ABC Main",
                    Address2 = "My PO 1234",
                    Email = "abc@abc.com",
                    Mobile = "123456",
                    Phone = "123456"
                },
                new City { InternalId = 1, Label = "MyCity" },
                new State { InternalId = 1, Label = "MyState" },
                new Country { InternalId = 1, Label = "MyCountry" }
                );

//第二次电话

RegisterShipperAddress(shipperNode,
                new AddressType { TypeName = "BILLING" },
                new Address
                {
                    Address1 = "1 X Main Road",
                    Address2 = "PO 555",
                    Email = "abc@abc.com",
                    Mobile = "123456",
                    Phone = "123456"
                },
                new City { InternalId = 1, Label = "MyCity" },
                new State { InternalId = 1, Label = "MyState" },
                new Country { InternalId = 1, Label = "MyCountry" }
                );

我最终得到了同一个节点的多个实例。只是想知道是否可以使用Cypher的Create Unique子句来实现这一点。

这是我看到的那种图表..

               --> (Address1)-->(MyCity)-->(MyState)-->(MyCountry)

（root） - ＆gt;（发件人）||

               --> (Address2)-->(MyCity)-->(MyState)-->(MyCountry)

同样，在一个事务中一次创建多个节点的最佳方法，我认为在上面的代码中，每个节点都是在一个单独的事务中创建的。

Answer 1

不鼓励Cypher 1.9中的

CREATE UNIQUE。如果可以的话，请使用Neo4j 2.0.0.M05 ++并在城市，州和国家/地区创建一个独特的约束，请参阅http://docs.neo4j.org/chunked/snapshot/query-constraints.html#constraints-create-uniqueness-constraint然后MERGE城市节点，创建地址。这是一个graphgist示例：

http://gist.neo4j.org/?6549962

Neo4jClient在多个重复节点中创建唯一结果

1 个答案: