Oihana PHP Arango

EdgesCountTrait uses trait:short

Provides utilities for counting relationships (edges) and unique neighbors (vertices) in an ArangoDB edge collection.

This trait extends ArangoTrait and VerticesTrait and offers two distinct counting strategies:

1. Edge Counting (via countEdges)

What it does: Counts the actual edge documents that match a filter (e.g., _from == 'A' AND _to == 'B'). It uses RETURN LENGTH(FOR ... FILTER ...)

Use case: Answers "How many times does relation X exist?"

Example: If 'user/1' follows 'user/2' twice (two edge documents), countEdges('user/1', 'user/2') will return 2.

2. Vertex Counting (via countVertices, countOutboundVertices, etc.)

What it does: Counts the unique vertex documents reached by a traversal (OUTBOUND, INBOUND, ANY). It uses FOR ... COLLECT WITH COUNT.

Use case: Answers "How many unique neighbors does vertex X have?"

Example:

If 'user/1' follows 'user/2' twice, countOutboundVertices('user/1') will return 1 (as 'user/2' is one unique vertex).

Usage

$edges = new Edges($container, ['collection' => 'user_follows']);

// How many edge documents connect 'users/1' to 'posts/5'?
$edgeCount = $edges->countEdges('users/1', 'posts/5');

// How many unique users does 'users/1' follow?
$vertexCount = $edges->countOutboundVertices('users/1');
Tags
author

Marc Alcaraz (eKameleon)

version
1.0.0

Table of Contents

Methods

countAnyVertices()  : int
Counts all unique vertices connected in any direction from the given vertex.
countEdges()  : int
Counts the number of edge documents matching the specified vertices.
countInboundVertices()  : int
Counts all unique inbound vertices connected to the given 'to' vertex.
countOutboundVertices()  : int
Counts all unique outbound vertices connected from the given 'from' vertex.
countVertices()  : int
Counts all vertices connected with a specific direction.
prepareTraversal()  : array{0: array, 1: string|array|null, 2: string|null, 3: string|null, 4: string}
Prepares traversal parameters and returns key elements required to execute a vertex traversal query.
countEdgesQuery()  : string
Generates the count query and fill the binds array reference.
prepareTraversalWith()  : string
Derives the AQL `WITH` clause declaring the vertex collections reached by an **anonymous** traversal (edge collection, no named graph).

Methods

countAnyVertices()

Counts all unique vertices connected in any direction from the given vertex.

public countAnyVertices([string|null $vertex = null ][, array<string|int, mixed> $init = [] ]) : int

This is a convenience method for countVertices(Traversal::ANY, ...). It counts unique neighbors (vertices), not relations (edges).

Parameters
$vertex : string|null = null

Optional '_key' or '_id' of the vertex to start from.

$init : array<string|int, mixed> = []

Optional query initialization array (e.g., AQL::GRAPH).

Tags
throws
ArangoException
BindException
ConstantException
ContainerExceptionInterface
DependencyException
NotFoundException
NotFoundExceptionInterface
ReflectionException
Return values
int —

The total count of unique connected vertices.

countEdges()

Counts the number of edge documents matching the specified vertices.

public countEdges([string|null $from = null ][, string|null $to = null ][, array<string|int, mixed> $init = [] ]) : int

This counts the relations (edges), not the unique neighbors.

Parameters
$from : string|null = null

Optional '_from' vertex identifier.

$to : string|null = null

Optional '_to' vertex identifier.

$init : array<string|int, mixed> = []

Optional query options (e.g., AQL::BINDS, operator => Logic::OR).

Tags
throws
ArangoException
BindException
ContainerExceptionInterface
DependencyException
NotFoundException
NotFoundExceptionInterface
ReflectionException
Return values
int —

The total count of matching edge documents.

countInboundVertices()

Counts all unique inbound vertices connected to the given 'to' vertex.

public countInboundVertices([string|null $to = null ][, array<string|int, mixed> $init = [] ]) : int

This is a convenience method for countVertices(Traversal::INBOUND, ...). It counts unique neighbors (vertices), not relations (edges).

Parameters
$to : string|null = null

Optional '_key' or '_id' of the vertex to traverse to.

$init : array<string|int, mixed> = []

Optional query initialization array (e.g., AQL::GRAPH).

Tags
throws
ArangoException
BindException
ConstantException
ContainerExceptionInterface
DependencyException
NotFoundException
NotFoundExceptionInterface
ReflectionException
Return values
int —

The total count of unique inbound vertices.

countOutboundVertices()

Counts all unique outbound vertices connected from the given 'from' vertex.

public countOutboundVertices([string|null $from = null ][, array<string|int, mixed> $init = [] ]) : int

This is a convenience method for countVertices(Traversal::OUTBOUND, ...). It counts unique neighbors (vertices), not relations (edges).

Parameters
$from : string|null = null

Optional '_key' or '_id' of the vertex to start from.

$init : array<string|int, mixed> = []

Optional query initialization array (e.g., AQL::GRAPH).

Tags
throws
ArangoException
BindException
ConstantException
ContainerExceptionInterface
DependencyException
NotFoundException
NotFoundExceptionInterface
ReflectionException
Return values
int —

The total count of unique outbound vertices.

countVertices()

Counts all vertices connected with a specific direction.

public countVertices(string $direction[, string|null $vertex = null ][, array{vertexRef?: string, edgeRef?: string|null, pathRef?: string|null, direction?: string, startVertex?: string, graph?: string|null, edgeCollection?: array|string|null, minDepth?: int|null, maxDepth?: int|null, prune?: string|array|null, options?: array|object|string|null, filter?: string|array|null, binds?: array, from?: string|null, to?: string|null, anyRef?: string|null, docRef?: string|null} $init = [] ]) : int

This counts the destination vertex documents.

Parameters
$direction : string

The direction of the relation: Traversal::OUTBOUND, Traversal::INBOUND, or Traversal::ANY.

$vertex : string|null = null

Optional '_key' or '_id' of the vertex to start the relation from.

$init : array{vertexRef?: string, edgeRef?: string|null, pathRef?: string|null, direction?: string, startVertex?: string, graph?: string|null, edgeCollection?: array|string|null, minDepth?: int|null, maxDepth?: int|null, prune?: string|array|null, options?: array|object|string|null, filter?: string|array|null, binds?: array, from?: string|null, to?: string|null, anyRef?: string|null, docRef?: string|null} = []

Optional query initialization and configuration array.

Tags
throws
ArangoException
BindException
ConstantException
ContainerExceptionInterface
DependencyException
NotFoundException
NotFoundExceptionInterface
ReflectionException
Return values
int —

The total count of matching vertices.

prepareTraversal()

Prepares traversal parameters and returns key elements required to execute a vertex traversal query.

public prepareTraversal(string $direction[, string|null $vertex = null ][, array{vertexRef?: string, edgeRef?: string|null, pathRef?: string|null, direction?: string, startVertex?: string, graph?: string|null, edgeCollection?: array|string|null, minDepth?: int|null, maxDepth?: int|null, prune?: string|array|null, options?: array|object|string|null, filter?: string|array|null, binds?: array, from?: string|null, to?: string|null, anyRef?: string|null, docRef?: string|null} &$init = [] ]) : array{0: array, 1: string|array|null, 2: string|null, 3: string|null, 4: string}

This method validates the direction, computes the full vertex ID, prepares bind variables, and sets default edge or graph collections if not provided. It is a utility for methods that fetch or count vertices via Traversal in an ArangoDB edge collection.

Parameters
$direction : string

The direction of traversal: Traversal::OUTBOUND, Traversal::INBOUND, or Traversal::ANY.

$vertex : string|null = null

Optional '_key' or '_id' of the vertex to start the traversal from. If null, the default $this->from or $this->to is used depending on the direction.

$init : array{vertexRef?: string, edgeRef?: string|null, pathRef?: string|null, direction?: string, startVertex?: string, graph?: string|null, edgeCollection?: array|string|null, minDepth?: int|null, maxDepth?: int|null, prune?: string|array|null, options?: array|object|string|null, filter?: string|array|null, binds?: array, from?: string|null, to?: string|null, anyRef?: string|null, docRef?: string|null} = []

Optional reference to array of query initialization and configuration.

Tags
throws
ConstantException

If the $direction is not a valid Traversal value.

InvalidArgumentException

If the resolved vertex ID is null or empty.

example 
[$binds, $filter, $from, $to, $vertexId] = $this->prepareTraversal(
    Traversal::OUTBOUND,
    '123',
    ['graph' => 'my_graph']
);
Return values
array{0: array, 1: string|array|null, 2: string|null, 3: string|null, 4: string} —

Returns an array containing: 0 => prepared bind variables, 1 => filter expression(s), 2 => "from" collection/vertex, 3 => "to" collection/vertex. 4 => resolved vertex ID,

countEdgesQuery()

Generates the count query and fill the binds array reference.

protected countEdgesQuery([string|null $from = null ][, string|null $to = null ][, array<string|int, mixed> &$binds = [] ][, array<string|int, mixed> $init = [] ]) : string
Parameters
$from : string|null = null

The from vertex identifier

$to : string|null = null

The to vertex identifier

$binds : array<string|int, mixed> = []

The bindVars array reference.

$init : array<string|int, mixed> = []

The option of the method.

  • 'collection' : The name of the collection, by default use the $this->collection property.
  • 'name' : The name of the bindVariable collection, by default use the @@collection.
  • 'operator' : Indicates if the filter of the vertices use a Logic::AND or Logic::OR operator (default Logic::AND)
  • 'variableName' : The name of the document in the query (default 'doc') AQL::DOC_REF
Tags
throws
BindException
ReflectionException
example 
[ $query , $binds ] = $this->countEdgeQuery( $from , $to ) ;
Return values
string —

The AQL query expression.

prepareTraversalWith()

Derives the AQL `WITH` clause declaring the vertex collections reached by an **anonymous** traversal (edge collection, no named graph).

private prepareTraversalWith(string $direction[, Documents|null $from = null ][, Documents|null $to = null ][, array<string|int, mixed> $init = [] ]) : string

In a cluster, collections accessed dynamically by collection-set traversals must be declared up front so they are all locked at query start, which avoids deadlocks. Named-graph traversals already know their collections, so this returns an empty string for them. The clause is harmless (a no-op) on a single server.

Declared collections, by direction:

An explicit AQL::WITH entry in $init (a collection name or an array of names) overrides the direction-based derivation.

Parameters
$direction : string

Traversal direction (Traversal).

$from : Documents|null = null

The _from vertex model (may be null).

$to : Documents|null = null

The _to vertex model (may be null).

$init : array<string|int, mixed> = []

The traversal init array (read-only here).

Tags
see
https://docs.arangodb.com/stable/aql/high-level-operations/with/
Return values
string —

The WITH coll1, coll2, ... clause, or an empty string when there is nothing to declare (named graph, missing models, or explicit empty).

On this page

Search results