Question

使用Community Edition 2.1.11

我在互联网上看到了一些类似的问题（例如，import edges to OrientDB using etl或orient-database.narkive.com/d8c4b82y/orientdb-etl-edge-creation-help），但它们尚未真正得到解决。

我正在实施航班连接搜索系统。我有RDBMS（SQL Server）和两个相关的表 - 位置和航班。每个航班都有两个locationID - locationFrom和locationTo。

当我将其导入图表时，我希望将位置视为顶点，并将航班与边缘相关联。正如我从手册中所理解的那样（从DBMS导入，由于新手限制，我不能发布两个以上的链接......），我应该为此目的编写两个不同的JSON并由ETL运行它们。因此，我可以使用此代码导入位置而不会出现任何问题：

    {
  "config": {
    log : "debug"
  },
  "extractor" : {
    "jdbc": { "driver": "com.microsoft.sqlserver.jdbc.SQLServerDriver",
              "url": "jdbc:sqlserver://localhost:1434;databaseName=mydb;integratedSecurity=true;",
              "userName": "root",
              "userPassword": "root",
              "query": "select * from locations" }
  },

  "transformers" : [
    { "vertex": { "class": "Location"} }
  ],
   "loader" : {
    "orientdb": {
      "dbURL": "plocal:C:\orientdb-community-2.1.11\databases\Test",
      dbUser: "admin",
      dbPassword: "admin",
      dbAutoDropIfExists: false,
      dbAutoCreate: true,
      tx: false,
      wal: false,
      batchCommit: 1000,
      dbType: "graph",
      indexes: [{class:"Location", fields:["id:string"], type:"UNIQUE_HASH_INDEX" }]
    }
  }
}

但是当我尝试导入航班时，我遇到了一个问题，即使使用谷歌的帮助我也无法解决：ETL不想只导入边缘。作为第一个直观的目的，我写了类似的东西：

{
  "config": {
    log : "debug"
  },
  "extractor" : {
    "jdbc": { "driver": "com.microsoft.sqlserver.jdbc.SQLServerDriver",
              "url": "jdbc:sqlserver://localhost:1434;databaseName=mydb;integratedSecurity=true;",
              "userName": "root",
              "userPassword": "root",
              "query": "select * from flights" }
  },

  "transformers" : [
    { "edge": { "class": "flight", "direction" : "out", 
            "joinFieldName": "flightFromLocation",
            "lookup":"locationID", "unresolvedLinkAction":"CREATE"}

            { "class": "flight", "direction" : "in", 
            "joinFieldName": "flightToLocation",
            "lookup":"locationID", "unresolvedLinkAction":"CREATE"}
    }
  ],
   "loader" : {
    "orientdb": {
      "dbURL": "plocal:C:\orientdb-community-2.1.11\databases\Test",
      dbUser: "admin",
      dbPassword: "admin",
      dbAutoDropIfExists: false,
      dbAutoCreate: true,
      tx: false,
      wal: false,
      batchCommit: 1000,
      dbType: "graph",
      indexes: [{class:"flight", fields:["id:string"], type:"UNIQUE_HASH_INDEX" }]
    }
  }
}

在OrientDB的GoogleGroups的一个主题中，我发现了一个来自OrientDB的post from Luca，它表示只能通过ETL加载边缘，但我仍然无法弄清楚，如何实现它:(只有想法，我有两天的阅读文档和谷歌搜索是将它们作为顶点导入，然后编写一些控制台JS函数，将创建具有相同属性的正确边... ...

或许我错过了一些非常基本的东西？我对东方来说是全新的......

Answer 1

执行所需操作的简单方法是使用正常的ETL过程将两个表导入两个顶点类，然后使用js函数创建边。

我创建此数据集以在导入两个表后重新创建您的情况：

这是JS函数：

参数：flights_V_class，edge_class，location_class

var g=orient.getGraphNoTx();


var flightsV_table = g.command("sql","select from " + flights_V_class);

for(i=0; i < flightsV_table.length; i++){

  var id_from = flightsV_table[i].getProperty("locationFrom");

  var id_to = flightsV_table[i].getProperty("locationTo");

  var select_from = "select from "+location_class+" where id = "+id_from;
  var select_to = "select from "+location_class+" where id = "+id_to;

  g.command("sql","create edge " + edge_class + " from (" + select_from + ") to (" + select_to + ")");
}

执行此功能后，这是我的数据：

然后，毕竟，你可以删除临时flight_V类。

希望它有所帮助。再见。

伊万

Answer 2

我试过MySQL

我创建了位置和航班

Location.json

{
  "config": {
    log : "debug"
  },
  "extractor" : {
    "jdbc": { "driver": "com.mysql.jdbc.Driver",
              "url": "jdbc:mysql://localhost:3306/flights",
              "userName": "user",
              "userPassword": "password",
              "query": "select * from Location" 
              }
  },
  "transformers" : [
    { "vertex": { "class": "Location"} }
  ],
   "loader" : {
    "orientdb": {
      "dbURL": "yourPath",
      "dbUser": "admin",
      "dbPassword": "admin",
      "dbAutoDropIfExists": false,
      "dbAutoCreate": true,
      "tx": false,
      "wal": false,
      "batchCommit": 1000,
      "dbType": "graph",
      "indexes": [{class:"Location", fields:["id:string"], type:"UNIQUE_HASH_INDEX" }]
    }
  }
}

Flight.json

{
  "config": {
    log : "debug"
  },
  "extractor" : {
    "jdbc": { "driver": "com.mysql.jdbc.Driver",
              "url": "jdbc:mysql://localhost:3306/flights",
              "userName": "user",
              "userPassword": "password",
              "query": "select * from flight" 
              }
  },
  "transformers" : [
    { "vertex": { "class": "Fligth"} }
  ],
   "loader" : {
    "orientdb": {
      "dbURL": "yourPath",
      "dbUser": "admin",
      "dbPassword": "admin",
      "dbAutoDropIfExists": false,
      "dbAutoCreate": true,
      "tx": false,
      "wal": false,
      "batchCommit": 1000,
      "dbType": "graph",
      "indexes": [{class:"flight", fields:["id:string"], type:"UNIQUE_HASH_INDEX" }]
    }
  }
}

etl进程导入了以下记录

您可以使用此JavaScript函数

var g=orient.getGraphNoTx();
g.command("sql","CREATE CLASS Fligth2 EXTENDS E");
var fligth = g.command("sql","select from Fligth");
for(i=0;i<fligth.length;i++){
    var idFrom=fligth[i].getProperty("idFrom");
    var idTo=fligth[i].getProperty("idTo");
    var name=fligth[i].getProperty("name");
    print(name);
    var from=g.command("sql","select from Location where id = " +  idFrom);
    var to=g.command("sql","select from Location where id = " +  idTo);
    g.command("sql","create edge Fligth2 from " + from[0].getId() + " to " + to[0].getId() + " set name = '" + name + "'");
}
g.command("sql","drop class Fligth unsafe");
g.command("sql","UPDATE Location REMOVE id");

你应该有这个结构

从RDBMS导入到OrientDB：仅加载边

2 个答案: