Find Edges

Overview

The find().edges() statement retrieves edges from the current graphset that meet the given conditions.

Syntax

Syntax
find().edges(<filter?>)

• Statement alias: Type EDGE; default is edges
• Methods:

Example Graph

To create the graph, execute each of the following UQL queries sequentially in an empty graphset:

UQL
create().node_schema("User").node_schema("Club").edge_schema("Follows").edge_schema("Joins")
create().node_property(@User, "name").node_property(@Club, "name").edge_property(@Follows, "time", datetime).edge_property(@Joins, "memberNo", uint32).edge_property(@Joins, "time", datetime)
insert().into(@User).nodes([{_id:"U01", name:"Rowlock"},{_id:"U02", name:"Brainy"},{_id:"U03", name:"purplechalk"},{_id:"U04", name:"mochaeach"},{_id:"U05", name:"lionbower"}])
insert().into(@Club).nodes([{_id:"C01", name:"Rowlock Tennis"},{_id:"C02", name:"Super Yacht"}])
insert().into(@Follows).edges([{_from:"U01", _to:"U02", time:"2024-1-5"},{_from:"U02", _to:"U03", time:"2024-2-1"},{_from:"U04", _to:"U02", time:"2024-2-10"},{_from:"U03", _to:"U05", time:"2024-5-3"}])
insert().into(@Joins).edges([{_from:"U02", _to:"C01", memberNo:1, time:"2023-12-14"},{_from:"U05", _to:"C01", memberNo:2, time:"2024-2-25"},{_from:"U04", _to:"C02", memberNo:9, time:"2024-6-15"}])

Finding All Edges

To retrieve all edges:

UQL
find().edges() as e
return e{*}

Result: e

Finding Edges with Schemas

To retrieve edges belonging to the schema Joins:

UQL
find().edges({@Joins}) as e
return e{*}

Result: e

To retrieve edges belonging to the schema Joins or Follows:

UQL
find().edges({@Joins || @Follows}) as e
return e{*}

Result: e

Finding Edges with Properties

In filters, properties can either be associated with a schema or used independently. When used independently, these properties apply to all edges that contain them, regardless of schema. Specifically, system properties _uuid, _from, _to, _from_uuid, and _to_uuid cannot be used with a schema (e.g., @Joins._uuid).

To retrieve @Joins edges where memberNo is 2:

UQL
find().edges({@Joins.memberNo == 2}) as e
return e.time

Result:

To retrieve edges where time is greater than 2024-5-1:

UQL
find().edges({time > "2024-5-1"}) as e
return e{*}

Result: e

To retrieve edges where _from is "U01" or "U04":

UQL
find().edges({_from in ["U01", "U04"]}) as e
return e{*}

Result: e

Using Default Alias

You can use the default alias edges for the find().edges() statement without explicitly declaring it.

To retrieve all edges and return their time (with schema and system properties returned by default):

UQL
find().edges()
return edges{time}

Result: edges

Limiting the Number of Edges

You can use the LIMIT statement immediately after the find().edges() statement to restrict the number of edges passed to subsequent statements.

To retrieve any 3 @Follows edges:

UQL
find().edges({@Follows}) as e limit 3
return e.time

Result:

Using limit()

In this query, the find().edges() statement executes two times, each time using one record from t. With the limit() method, only one edge is retrieved each time:

UQL
uncollect ["2024-1-1", "20224-5-1"] as t
call {
    with t
    find().edges({@Follows.time > t}).limit(1) as e
    return e
}
return e{*}

Result: e

Using OPTIONAL

In this query, the find().edges() statement executes three times, each time using one record from num. With the OPTIONAL prefix, the query returns null if no result is found during execution:

UQL
uncollect [1,2,3] as num
optional find().edges({memberNo == num}) as e
return e.time

Result:

Without the prefix OPTIONAL, only two records are returned:

UQL
uncollect [1,2,3] as num
find().edges({memberNo == num}) as e
return e.time

Result: