Graph Management

This chapter describes the JavaScript interface for creating and modifying named graphs.

Edge Definitions

An edge definition is always a directed relation of a graph. Each graph can have arbitrary many relations defined within the edge definitions array.

Initialize the List

Create a list of edge definitions to construct a graph:

graph_module._edgeDefinitions(relation1, relation2, ..., relationN)

• relation (object, optional): An object representing a definition of one relation in the graph

The list of edge definitions of a graph can be managed by the graph module itself. This function is the entry point for the management and returns the correct list.

Examples

var graph_module = require("@arangodb/general-graph");
var directed_relation = graph_module._relation("lives_in", "user", "city");
var undirected_relation = graph_module._relation("knows", "user", "user");
var edgedefinitions = graph_module._edgeDefinitions(directed_relation, undirected_relation);
edgedefinitions;

[ 
  { 
    "collection" : "lives_in", 
    "from" : [ 
      "user" 
    ], 
    "to" : [ 
      "city" 
    ] 
  }, 
  { 
    "collection" : "knows", 
    "from" : [ 
      "user" 
    ], 
    "to" : [ 
      "user" 
    ] 
  } 
]

Extend the List

Extend the list of edge definitions to construct a graph:

graph_module._extendEdgeDefinitions(edgeDefinitions, relation1, relation2, ..., relationN)

• edgeDefinitions (array): A list of relation definition objects.
• relationX (object): An object representing a definition of one relation in the graph

In order to add more edge definitions to the graph before creating it, this function can be used to add more definitions to the initial list.

Examples

var graph_module = require("@arangodb/general-graph");
var directed_relation = graph_module._relation("lives_in", "user", "city");
var undirected_relation = graph_module._relation("knows", "user", "user");
var edgedefinitions = graph_module._edgeDefinitions(directed_relation);
graph_module._extendEdgeDefinitions(edgedefinitions, undirected_relation);
edgedefinitions;

[ 
  { 
    "collection" : "lives_in", 
    "from" : [ 
      "user" 
    ], 
    "to" : [ 
      "city" 
    ] 
  }, 
  { 
    "collection" : "knows", 
    "from" : [ 
      "user" 
    ], 
    "to" : [ 
      "user" 
    ] 
  } 
]

Relation

Define a directed relation:

graph_module._relation(relationName, fromVertexCollections, toVertexCollections)

• relationName (string): The name of the edge collection where the edges should be stored. It is created if it does not exist yet.
• fromVertexCollections (string|array): One or a list of collection names. Source vertices for the edges have to be stored in these collections. Collections are created if they do not exist.
• toVertexCollections (string|array): One or a list of collection names. Target vertices for the edges have to be stored in these collections. Collections are created if they do not exist.

The relationName defines the name of this relation and references to the underlying edge collection. The fromVertexCollections is an Array of document collections holding the start vertices. The toVertexCollections is an array of document collections holding the target vertices. Relations are only allowed in the direction from any collection in fromVertexCollections to any collection in toVertexCollections.

Examples

A relation from one vertex collection to another:

var graph_module = require("@arangodb/general-graph");
graph_module._relation("has_bought", "Customer", "Product");

{ 
  "collection" : "has_bought", 
  "from" : [ 
    "Customer" 
  ], 
  "to" : [ 
    "Product" 
  ] 
}

A relation from multiple vertex collections to multiple others:

var graph_module = require("@arangodb/general-graph");
graph_module._relation("has_bought", ["Customer", "Company"], ["Groceries", "Electronics"]);

{ 
  "collection" : "has_bought", 
  "from" : [ 
    "Customer", 
    "Company" 
  ], 
  "to" : [ 
    "Groceries", 
    "Electronics" 
  ] 
}

Edge Definition Options

The following edge definition options are supported:

• satellites (array, optional): An array of collection names that is used to create SatelliteCollections for a (Disjoint) SmartGraph using SatelliteCollections (Enterprise Edition only). Each array element must be a string and a valid collection name. The collection type cannot be modified later.

Create a Graph

graph_module._create(graphName, edgeDefinitions, orphanCollections)

• graphName (string): Unique identifier of the graph
• edgeDefinitions (array, optional): List of relation definition objects
• orphanCollections (array, optional): List of additional vertex collection names

The creation of a graph requires the name of the graph and a definition of its edges.

For every type of edge definition a convenience method exists that can be used to create a graph. Optionally a list of vertex collections can be added, which are not used in any edge definition. These collections are referred to as orphan collections within this chapter. All collections used within the creation process are created if they do not exist.

Examples

Create an empty graph, edge definitions can be added at runtime:

var graph_module = require("@arangodb/general-graph");
graph = graph_module._create("myGraph");

{[GeneralGraph] 
}

Create a graph using an edge collection edges and a single vertex collection vertices:

var graph_module = require("@arangodb/general-graph");
var edgeDefinitions = [ { collection: "edges", "from": [ "vertices" ], "to" : [ "vertices" ] } ];
graph = graph_module._create("myGraph", edgeDefinitions);

{[GeneralGraph] 
  "edges" : [ArangoCollection 77375, "edges" (type edge, status loaded)], 
  "vertices" : [ArangoCollection 77372, "vertices" (type document, status loaded)] 
}

Create a graph with edge definitions and orphan collections:

var graph_module = require("@arangodb/general-graph");
graph = graph_module._create("myGraph", [
  graph_module._relation("myRelation", ["male", "female"], ["male", "female"])
], ["sessions"]);

{[GeneralGraph] 
  "myRelation" : [ArangoCollection 77413, "myRelation" (type edge, status loaded)], 
  "female" : [ArangoCollection 77410, "female" (type document, status loaded)], 
  "male" : [ArangoCollection 77407, "male" (type document, status loaded)], 
  "sessions" : [ArangoCollection 77404, "sessions" (type document, status loaded)] 
}

Complete Example to Create a Graph

Example call:

var graph_module = require("@arangodb/general-graph");
var edgeDefinitions = graph_module._edgeDefinitions();
graph_module._extendEdgeDefinitions(edgeDefinitions, graph_module._relation("friend_of", "Customer", "Customer"));
graph_module._extendEdgeDefinitions(edgeDefinitions, graph_module._relation(
  "has_bought", ["Customer", "Company"], ["Groceries", "Electronics"])
);
graph_module._create("myStore", edgeDefinitions);

{[GeneralGraph] 
  "friend_of" : [ArangoCollection 77472, "friend_of" (type edge, status loaded)], 
  "Customer" : [ArangoCollection 77461, "Customer" (type document, status loaded)], 
  "has_bought" : [ArangoCollection 77467, "has_bought" (type edge, status loaded)], 
  "Company" : [ArangoCollection 77464, "Company" (type document, status loaded)], 
  "Electronics" : [ArangoCollection 77458, "Electronics" (type document, status loaded)], 
  "Groceries" : [ArangoCollection 77455, "Groceries" (type document, status loaded)] 
}

Alternative call:

var graph_module = require("@arangodb/general-graph");
var edgeDefinitions = graph_module._edgeDefinitions(
  graph_module._relation("friend_of", ["Customer"], ["Customer"]),
  graph_module._relation("has_bought", ["Customer", "Company"], ["Groceries", "Electronics"])
);
graph_module._create("myStore", edgeDefinitions);

{[GeneralGraph] 
  "friend_of" : [ArangoCollection 77514, "friend_of" (type edge, status loaded)], 
  "Customer" : [ArangoCollection 77503, "Customer" (type document, status loaded)], 
  "has_bought" : [ArangoCollection 77509, "has_bought" (type edge, status loaded)], 
  "Company" : [ArangoCollection 77506, "Company" (type document, status loaded)], 
  "Electronics" : [ArangoCollection 77500, "Electronics" (type document, status loaded)], 
  "Groceries" : [ArangoCollection 77497, "Groceries" (type document, status loaded)] 
}

List available Graphs

Lists all graph names stored in this database:

graph_module._list()

Lists all graph definitions stored in this database:

graph_module._listObjects()

Examples

List the graph names:

var graph_module = require("@arangodb/general-graph");
graph_module._list();

[ 
  "myGraph", 
  "myStore" 
]

List the graph definitions:

var graph_module = require("@arangodb/general-graph");
graph_module._listObjects();

[ 
  { 
    "_id" : "_graphs/myGraph", 
    "_key" : "myGraph", 
    "_rev" : "_holfuFG--_", 
    "edgeDefinitions" : [ 
      { 
        "collection" : "edges", 
        "from" : [ 
          "vertices" 
        ], 
        "to" : [ 
          "vertices" 
        ] 
      } 
    ], 
    "orphanCollections" : [ ], 
    "name" : "myGraph" 
  }, 
  { 
    "_id" : "_graphs/myStore", 
    "_key" : "myStore", 
    "_rev" : "_holfuFK--_", 
    "edgeDefinitions" : [ 
      { 
        "collection" : "friend_of", 
        "from" : [ 
          "Customer" 
        ], 
        "to" : [ 
          "Customer" 
        ] 
      }, 
      { 
        "collection" : "has_bought", 
        "from" : [ 
          "Company", 
          "Customer" 
        ], 
        "to" : [ 
          "Electronics", 
          "Groceries" 
        ] 
      } 
    ], 
    "orphanCollections" : [ ], 
    "name" : "myStore" 
  } 
]

Load a Graph

Get a graph by its name:

graph_module._graph(graphName)

• graphName (string): Unique identifier of the graph

Examples

var graph_module = require("@arangodb/general-graph");
graph = graph_module._graph("social");

{[GeneralGraph] 
  "relation" : [ArangoCollection 77672, "relation" (type edge, status loaded)], 
  "female" : [ArangoCollection 77662, "female" (type document, status loaded)], 
  "male" : [ArangoCollection 77667, "male" (type document, status loaded)] 
}

Remove a Graph

Drop a Graph by its name:

graph_module._drop(graphName, dropCollections)

• graphName (string): Unique identifier of the graph
• dropCollections (bool, optional): Define if collections should be dropped (default: false)

This can drop all collections contained in the graph as long as they are not used within other graphs. To drop the collections only belonging to this graph, the optional parameter drop-collections has to be set to true.

Examples

Drop a graph and keep collections:

var graph_module = require("@arangodb/general-graph");
graph_module._graph("social");
graph_module._drop("social");
db._collection("female");
db._collection("male");
db._collection("relation");

{[GeneralGraph] 
  "relation" : [ArangoCollection 77732, "relation" (type edge, status loaded)], 
  "female" : [ArangoCollection 77722, "female" (type document, status loaded)], 
  "male" : [ArangoCollection 77727, "male" (type document, status loaded)] 
}
[ArangoCollection 77722, "female" (type document, status loaded)]

[ArangoCollection 77727, "male" (type document, status loaded)]

[ArangoCollection 77732, "relation" (type edge, status loaded)]

Drop a graph and its collections:

var graph_module = require("@arangodb/general-graph");
graph_module._graph("social");
graph_module._drop("social", true);
db._collection("female");
db._collection("male");
db._collection("relation");

{[GeneralGraph] 
  "relation" : [ArangoCollection 77780, "relation" (type edge, status loaded)], 
  "female" : [ArangoCollection 77770, "female" (type document, status loaded)], 
  "male" : [ArangoCollection 77775, "male" (type document, status loaded)] 
}
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Modify a Graph definition at runtime

After you have created a graph its definition is not immutable. You can still add, delete or modify edge definitions and vertex collections.

Extend the Edge Definitions

Add another edge definition to the graph:

graph._extendEdgeDefinitions(edgeDefinition, options)

• edgeDefinition (object): The relation definition to extend the graph
• options (object): Additional options related to the edge definition itself. See Edge Definition Options.

Extends the edge definitions of a graph. If an orphan collection is used in this edge definition, it is removed from the orphanage. If the edge collection of the edge definition to add is already used in the graph or used in a different graph with different from and/or to collections an error is thrown.

Examples

var graph_module = require("@arangodb/general-graph")
var ed1 = graph_module._relation("myEC1", ["myVC1"], ["myVC2"]);
var ed2 = graph_module._relation("myEC2", ["myVC1"], ["myVC3"]);
var graph = graph_module._create("myGraph", [ed1]);
graph._extendEdgeDefinitions(ed2);
graph = graph_module._graph("myGraph");

{[GeneralGraph] 
  "myEC1" : [ArangoCollection 77840, "myEC1" (type edge, status loaded)], 
  "myVC1" : [ArangoCollection 77837, "myVC1" (type document, status loaded)], 
  "myVC2" : [ArangoCollection 77834, "myVC2" (type document, status loaded)], 
  "myEC2" : [ArangoCollection 77858, "myEC2" (type edge, status loaded)], 
  "myVC3" : [ArangoCollection 77855, "myVC3" (type document, status loaded)] 
}

Modify an Edge Definition

Modify a relation definition:

graph_module._editEdgeDefinitions(edgeDefinition, options)

• edgeDefinition (object): The edge definition to replace the existing edge definition with the same attribute collection.
• options (object): Additional options related to the edge definition itself. See Edge Definition Options.

Edits one relation definition of a graph. The edge definition used as argument replaces the existing edge definition of the graph which has the same collection. Vertex Collections of the replaced edge definition that are not used in the new definition are transformed to an orphan. Orphans that are used in this new edge definition are deleted from the list of orphans. Other graphs with the same edge definition are modified, too.

Examples

var graph_module = require("@arangodb/general-graph")
var original = graph_module._relation("myEC1", ["myVC1"], ["myVC2"]);
var modified = graph_module._relation("myEC1", ["myVC2"], ["myVC3"]);
var graph = graph_module._create("myGraph", [original]);
graph._editEdgeDefinitions(modified);
graph = graph_module._graph("myGraph");

{[GeneralGraph] 
  "myEC1" : [ArangoCollection 77909, "myEC1" (type edge, status loaded)], 
  "myVC2" : [ArangoCollection 77903, "myVC2" (type document, status loaded)], 
  "myVC3" : [ArangoCollection 77922, "myVC3" (type document, status loaded)], 
  "myVC1" : [ArangoCollection 77906, "myVC1" (type document, status loaded)] 
}

Delete an Edge Definition

Delete one relation definition:

graph_module._deleteEdgeDefinition(edgeCollectionName, dropCollection)

• edgeCollectionName (string): Name of edge collection in the relation definition.
• dropCollection (bool, optional): Define if the edge collection should be dropped. Default: false

Deletes a relation definition defined by the edge collection of a graph. If the collections defined in the edge definition (collection, from, to) are not used in another edge definition of the graph, they are moved to the orphanage.

Examples

Remove an edge definition but keep the edge collection:

var graph_module = require("@arangodb/general-graph")
var ed1 = graph_module._relation("myEC1", ["myVC1"], ["myVC2"]);
var ed2 = graph_module._relation("myEC2", ["myVC1"], ["myVC3"]);
var graph = graph_module._create("myGraph", [ed1, ed2]);
graph._deleteEdgeDefinition("myEC1");
graph = graph_module._graph("myGraph");
db._collection("myEC1");

{[GeneralGraph] 
  "myEC2" : [ArangoCollection 77973, "myEC2" (type edge, status loaded)], 
  "myVC1" : [ArangoCollection 77970, "myVC1" (type document, status loaded)], 
  "myVC3" : [ArangoCollection 77964, "myVC3" (type document, status loaded)], 
  "myVC2" : [ArangoCollection 77967, "myVC2" (type document, status loaded)] 
}

[ArangoCollection 77978, "myEC1" (type edge, status loaded)]

Remove an edge definition and drop the edge collection:

var graph_module = require("@arangodb/general-graph")
var ed1 = graph_module._relation("myEC1", ["myVC1"], ["myVC2"]);
var ed2 = graph_module._relation("myEC2", ["myVC1"], ["myVC3"]);
var graph = graph_module._create("myGraph", [ed1, ed2]);
graph._deleteEdgeDefinition("myEC1", true);
graph = graph_module._graph("myGraph");
db._collection("myEC1");

{[GeneralGraph] 
  "myEC2" : [ArangoCollection 78035, "myEC2" (type edge, status loaded)], 
  "myVC1" : [ArangoCollection 78032, "myVC1" (type document, status loaded)], 
  "myVC3" : [ArangoCollection 78026, "myVC3" (type document, status loaded)], 
  "myVC2" : [ArangoCollection 78029, "myVC2" (type document, status loaded)] 
}

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Extend Vertex Collections

Each graph can have an arbitrary amount of vertex collections, which are not part of any edge definition of the graph. These collections are called orphan collections. If the graph is extended with an edge definition using one of the orphans, it is removed from the set of orphan collection automatically.

Add a Vertex Collection

Add a vertex collection to the graph:

graph._addVertexCollection(vertexCollectionName, createCollection, options)

• vertexCollectionName (string): Name of vertex collection.
• createCollection (bool, optional): If true, the collection is created if it does not exist. Default: true
• options (object, optional): Additional options related to the edge definition itself. See Edge Definition Options.

Adds a vertex collection to the set of orphan collections of the graph. If the collection does not exist, it is created. If it is already used by any edge definition of the graph, an error is thrown.

Examples

var graph_module = require("@arangodb/general-graph");
var ed1 = graph_module._relation("myEC1", ["myVC1"], ["myVC2"]);
var graph = graph_module._create("myGraph", [ed1]);
graph._addVertexCollection("myVC3", true);
graph = graph_module._graph("myGraph");

{[GeneralGraph] 
  "myEC1" : [ArangoCollection 78096, "myEC1" (type edge, status loaded)], 
  "myVC1" : [ArangoCollection 78093, "myVC1" (type document, status loaded)], 
  "myVC2" : [ArangoCollection 78090, "myVC2" (type document, status loaded)], 
  "myVC3" : [ArangoCollection 78109, "myVC3" (type document, status loaded)] 
}

Get the Orphaned Collections

Get all orphan collections:

graph._orphanCollections()

Returns all vertex collections of the graph that are not used in any edge definition.

Examples

var graph_module = require("@arangodb/general-graph")
var ed1 = graph_module._relation("myEC1", ["myVC1"], ["myVC2"]);
var graph = graph_module._create("myGraph", [ed1]);
graph._addVertexCollection("myVC3", true);
graph._orphanCollections();

[ 
  "myVC3" 
]

Remove a Vertex Collection

Remove a vertex collection from the graph:

graph._removeVertexCollection(vertexCollectionName, dropCollection)

• vertexCollectionName (string): Name of vertex collection.
• dropCollection (bool, optional): If true, the collection is dropped if it is not used in any other graph. Default: false

Removes a vertex collection from the graph. Only collections not used in any relation definition can be removed. Optionally the collection can be deleted, if it is not used in any other graph.

Examples

var graph_module = require("@arangodb/general-graph")
var ed1 = graph_module._relation("myEC1", ["myVC1"], ["myVC2"]);
var graph = graph_module._create("myGraph", [ed1]);
graph._addVertexCollection("myVC3", true);
graph._addVertexCollection("myVC4", true);
graph._orphanCollections();
graph._removeVertexCollection("myVC3");
graph._orphanCollections();

[ 
  "myVC3", 
  "myVC4" 
]
[ 
  "myVC4" 
]

Manipulating Vertices

Save a Vertex

Create a new vertex in vertexCollectionName:

graph.vertexCollectionName.save(data, options)

• data (object): JSON data of vertex.
• options (object, optional): See the collection object

Examples

var examples = require("@arangodb/graph-examples/example-graph");
var graph = examples.loadGraph("social");
graph.male.save({name: "Floyd", _key: "floyd"}, { returnNew: true });

{ 
  "_id" : "male/floyd", 
  "_key" : "floyd", 
  "_rev" : "_holfuaq--C", 
  "new" : { 
    "_key" : "floyd", 
    "_id" : "male/floyd", 
    "_rev" : "_holfuaq--C", 
    "name" : "Floyd" 
  } 
}

Replace a Vertex

Replaces the data of a vertex in collection vertexCollectionName:

graph.vertexCollectionName.replace(vertexId, data, options)

• vertexId (string): _id attribute of the vertex
• data (object): JSON data of vertex.
• options (object, optional): See the collection object

Examples

var examples = require("@arangodb/graph-examples/example-graph");
var graph = examples.loadGraph("social");
var doc = graph.male.save({neym: "Jon", _key: "john"});
graph.male.replace("male/john", {name: "John"}, { returnOld: true, returnNew: true });

{ 
  "_id" : "male/john", 
  "_key" : "john", 
  "_rev" : "_holfuci--_", 
  "_oldRev" : "_holfuci---", 
  "old" : { 
    "_key" : "john", 
    "_id" : "male/john", 
    "_rev" : "_holfuci---", 
    "neym" : "Jon" 
  }, 
  "new" : { 
    "_key" : "john", 
    "_id" : "male/john", 
    "_rev" : "_holfuci--_", 
    "name" : "John" 
  } 
}

Update a Vertex

Updates the data of a vertex in collection vertexCollectionName.

graph.vertexCollectionName.update(vertexId, data, options)

• vertexId (string): _id attribute of the vertex
• data (object): JSON data of vertex.
• options (object, optional): See the collection object

Examples

var examples = require("@arangodb/graph-examples/example-graph");
var graph = examples.loadGraph("social");
var doc = graph.female.save({name: "Lynda", _key: "linda"});
graph.female.update("female/linda", {name: "Linda", _key: "linda"}, { returnOld: true, returnNew: true });

{ 
  "_id" : "female/linda", 
  "_key" : "linda", 
  "_rev" : "_holfuem--_", 
  "_oldRev" : "_holfuem---", 
  "old" : { 
    "_key" : "linda", 
    "_id" : "female/linda", 
    "_rev" : "_holfuem---", 
    "name" : "Lynda" 
  }, 
  "new" : { 
    "_key" : "linda", 
    "_id" : "female/linda", 
    "_rev" : "_holfuem--_", 
    "name" : "Linda" 
  } 
}

Remove a Vertex

Removes a vertex in collection vertexCollectionName.

graph.vertexCollectionName.remove(vertexId, options)

• vertexId (string): _id attribute of the vertex
• options (object, optional): See the collection object

Additionally removes all ingoing and outgoing edges of the vertex recursively (see edge remove).

Examples

var examples = require("@arangodb/graph-examples/example-graph");
var graph = examples.loadGraph("social");
var doc = graph.male.save({name: "Kermit", _key: "kermit"});
db._exists("male/kermit");
var success = graph.male.remove("male/kermit");
db._exists("male/kermit");

true
false

Manipulating Edges

Save a new Edge

Creates an edge from vertex data._from to vertex data._to in collection edgeCollectionName.

graph.edgeCollectionName.save(data, options)

• data (object): JSON data of the edge. Needs to include a _from attribute with the document identifier of the source vertex and a _to attribute with the document identifier of the target vertex.
• options (object, optional): See the collection object

Examples

var examples = require("@arangodb/graph-examples/example-graph");
var graph = examples.loadGraph("social");
graph.relation.save({
  _from: "male/bob",
  _to: "female/alice",
  _key: "bobAndAlice", type: "married" }, { returnNew: true });

{ 
  "_id" : "relation/bobAndAlice", 
  "_key" : "bobAndAlice", 
  "_rev" : "_holfuiO--A", 
  "new" : { 
    "_key" : "bobAndAlice", 
    "_id" : "relation/bobAndAlice", 
    "_from" : "male/bob", 
    "_to" : "female/alice", 
    "_rev" : "_holfuiO--A", 
    "type" : "married" 
  } 
}

If the collections of from and to are not defined in an edge definition of the graph, the edge is not stored.

var examples = require("@arangodb/graph-examples/example-graph");
var graph = examples.loadGraph("social");
graph.relation.save(
  "relation/aliceAndBob",
   "female/alice",
  {type: "married", _key: "bobAndAlice"}); 

[ArangoError 1906: invalid edge between relation/aliceAndBob and female/alice. Doesn't conform to any edge definition]

Replace an Edge

Replaces the data of an edge in collection edgeCollectionName. Note that _from and _to are mandatory.

graph.edgeCollectionName.replace(edgeId, data, options)

• edgeId (string): _id attribute of the edge
• data (object, optional): JSON data of the edge
• options (object, optional): See the collection object

Examples

var examples = require("@arangodb/graph-examples/example-graph");
var graph = examples.loadGraph("social");
var doc = graph.relation.save("female/alice", "female/diana", {typo: "nose", _key: "aliceAndDiana"});
graph.relation.replace("relation/aliceAndDiana",
  { type: "knows", _from: "female/alice", _to: "female/diana" },
  { returnOld: true, returnNew: true });

{ 
  "_id" : "relation/aliceAndDiana", 
  "_key" : "aliceAndDiana", 
  "_rev" : "_holfumC--B", 
  "_oldRev" : "_holfumC--A", 
  "old" : { 
    "_key" : "aliceAndDiana", 
    "_id" : "relation/aliceAndDiana", 
    "_from" : "female/alice", 
    "_to" : "female/diana", 
    "_rev" : "_holfumC--A", 
    "typo" : "nose" 
  }, 
  "new" : { 
    "_key" : "aliceAndDiana", 
    "_id" : "relation/aliceAndDiana", 
    "_from" : "female/alice", 
    "_to" : "female/diana", 
    "_rev" : "_holfumC--B", 
    "type" : "knows" 
  } 
}

Update an Edge

Updates the data of an edge in collection edgeCollectionName.

graph.edgeCollectionName.update(edgeId, data, options)

• edgeId (string): _id attribute of the edge
• data (object, optional): JSON data of the edge
• options (object, optional): See the collection object

Examples

var examples = require("@arangodb/graph-examples/example-graph");
var graph = examples.loadGraph("social");
var doc = graph.relation.save("female/alice", "female/diana", {type: "knows", _key: "aliceAndDiana"});
graph.relation.update("relation/aliceAndDiana",
  { type: "quarreled", _key: "aliceAndDiana" },
  { returnOld: true, returnNew: true });

{ 
  "_id" : "relation/aliceAndDiana", 
  "_key" : "aliceAndDiana", 
  "_rev" : "_holfuny--B", 
  "_oldRev" : "_holfuny--A", 
  "old" : { 
    "_key" : "aliceAndDiana", 
    "_id" : "relation/aliceAndDiana", 
    "_from" : "female/alice", 
    "_to" : "female/diana", 
    "_rev" : "_holfuny--A", 
    "type" : "knows" 
  }, 
  "new" : { 
    "_key" : "aliceAndDiana", 
    "_id" : "relation/aliceAndDiana", 
    "_from" : "female/alice", 
    "_to" : "female/diana", 
    "_rev" : "_holfuny--B", 
    "type" : "quarreled" 
  } 
}

Remove an Edge

Removes an edge in collection edgeCollectionName.

graph.edgeCollectionName.remove(edgeId, options)

• edgeId (string): _id attribute of the edge
• options (object, optional): See the collection object

If this edge is used as a vertex by another edge, the other edge is removed (recursively).

Examples

var examples = require("@arangodb/graph-examples/example-graph");
var graph = examples.loadGraph("social");
var doc = graph.relation.save("female/alice", "female/diana", {_key: "aliceAndDiana"});
db._exists("relation/aliceAndDiana")
var success = graph.relation.remove("relation/aliceAndDiana")
db._exists("relation/aliceAndDiana")

true
false