OrientDB - Create Edge using kind of self join

问题

I have imported hierarchical data into OrientDB from RDMBS using OETL. In RDBMS we used to store parentId in the same row. e.g. the table structure is something like this:

ID - Name - Parent_ID

Corp - Corporate Office - Corp

D1 - District Office 1 - Corp

D2 - District Office 2 - Corp

SO1 - Small Office 1 - D1

SO2 - Small Office 2 - D2

SO3 - Small Office 3 - D1

Now each row is a node in Orientdb.

I want to create an edge (ParentOf) from say Corp to D1 and D1 to SO1 and so on.

How can I write a query to achieve this? Something along the line of following?

create edge parentOf from (select from node)a to (select from node where a.id = parent_id)

Sorry I am still thinking in relational db way.

Orient DB version is orientdb-community-2.0.9

回答1:

Thanks to pembeci, following is the function which finally did the trick:

var db = orient.getGraph();
var nodes = db.getVerticesOfClass("nodex");
var itr = nodes.iterator();

while(itr.hasNext()) {
   var vertex = itr.next();
   var id = vertex.getProperty("id");
   var children = db.getVertices("parent_id", id);
   var childItr = children.iterator();

   while(childItr.hasNext()) {
      var child = childItr.next();
      vertex.addEdge("parentOf", child);
   }
}

回答2:

You can't pass information from the first select query (from part) to the second query (to part). So you should possibly create a server side function. Something like this may work (I'll test it later, when I'll have access to Orient Studio):

var db = orient.getGraph;
var nodes = db.getVerticesOfClass("node");
for (var i=0; i<nodes.length; i++) {
   var vertex = nodes[i]
   var id = vertex.getProperty("id");
   var children = db.getVertices("parent_id", id);
   for (var j=0; j<children.length; j++) {
      var child = children[j];
      vertex.addEdge("parentOf", child)
   }
}

回答3:

The js function was running forever. Finally wrote java code to do this:

        OrientGraph graph = new OrientGraph("remote:localhost/testNode", "root", "root");

        for (Vertex v : graph.getVerticesOfClass("Node")) 
        {
            String id = v.getProperty("ID");    

            System.out.println("Checking children of: " + id);
            String sql = "select from node where PARENT_ID = '"+id+"'";

            for (Vertex child : (Iterable<Vertex>) graph.command(
                    new OCommandSQL(sql))
                    .execute()) 
            {
                v.addEdge("parent_of", child);
                System.out.println("\tAdded 'Parent Of' Edge from: " + id + " to " + child.getProperty("ID"));

            }               
            graph.commit();
        }

来源：https://stackoverflow.com/questions/30507054/orientdb-create-edge-using-kind-of-self-join

标签

OrientDB