AB
Overview
The clause ab().src().dest().depth() retrieves paths between a single source node and a single destination node.
Syntax
Clause Alias: PATH type
Method | Param Type | Param Spec | Required | Description | Alias |
|---|---|---|---|---|---|
src() | Filter | / | Yes | The conditions of the single source node; error occurs if multiple nodes are specified | NODE |
dest() | Filter | / | Yes | The conditions of the single destination node; error occurs if multiple nodes are specified | NODE |
depth() | Range | / | Yes | Depth of the paths (N≥1):depth(N): N edgesdepth(:N): 1~N edgesdepth(M:N): M~N edges (M≥0) | N/A |
shortest() | / or @<schema>.<property> | LTE-ed numeric edge property | No | Return the (weighted) shortest path. When an edge property (with non-negative values) is specified, edges without that property will not be considered The shortest() method only supports depth(N), indicating the (weighted) shortest paths within N steps | N/A |
node_filter() | Filter | / | No | The conditions that all intermediate nodes in the paths must satisfy | N/A |
edge_filter() | Filter | / | No | The conditions that all edges in the paths must satisfy | N/A |
path_ascend() | @<schema>.<property> | LTE-ed numeric edge property | No | Return paths where the specified property values ascend from source to destination (edges without the property will not be considered) | N/A |
path_descend() | @<schema>.<property> | LTE-ed numeric edge property | No | Return paths where the specified property values descend from source to destination (edges without the property will not be considered) | N/A |
direction() | String | left, right | No | Direction of all edges in the paths | N/A |
no_circle() | / | / | No | Paths with circles will not be returned Exception: When src() and dest() specify the same node and that node does not appear in any intermediate position, the path will still be returned | N/A |
limit() | Integer | ≥-1 | No | Number of results to return for each subquery, -1 signifies returning all | N/A |
Examples
Example Graph
Run these UQLs row by row in an empty graphset to create this graph:
UQLcreate().edge_property(@default, "weight", int32) insert().into(@default).nodes([{_id:"A", _uuid:1}, {_id:"B", _uuid:2}, {_id:"C", _uuid:3}, {_id:"D", _uuid:4}, {_id:"E", _uuid:5}, {_id:"F", _uuid:6}])Click to expand
Filter Depth
Example: Find 3-step paths from A to E, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(3) as p return p{*}
ResultA --1--> C <--4-- D <--5-- E
Example: Find 1~3-step paths from A to E, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(:3) as p return p{*}
ResultA --3--> E A --1--> C <--4-- D <--5-- E A <--6-- B <--2-- E
Example: Find 2~3-step paths from A to E, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(2:3) as p return p{*}
ResultA --1--> C <--4-- D <--5-- E A <--6-- B <-2-- E
Non-weighted Shortest Path
Example: Find shortest paths from A to E within 3 steps, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(3) .shortest() as p return p{*}
ResultA --3--> E
Weighted Shortest Path
Example: Find shortest paths from A to E within 3 steps, use @default.weight as weight, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(3) .shortest(@default.weight) as p return p{*}
ResultA <--6-- B <--2-- E
Analysis: Porperty @default.weight should be loaded to engine (LTE).
Filter Intermediate Nodes
Example: Find 1~3-step paths from A to E and not passing D, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(:3) .node_filter({_id != "D"}) as p return p{*}
ResultA --3--> E A <--6-- B <--2-- E
Filter Edges
Example: Find 1~3-step paths from A to E where the weight of edge is greater than 1, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(:3) .edge_filter({weight > 1}) as p return p{*}
ResultA --3--> E
Edge Property Ascend/Descend
Example: Find 1~3-step paths from A to E with property @default.weight ascending along the path, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(:3) .path_ascend(@default.weight) as p return p{*}
ResultA --3--> E A --1--> C <--4-- D <--5-- E
Analysis: Porperty @default.weight should be loaded to engine (LTE).
Example: Find 1~3-step paths from A to E with property @default.weight descending along the path, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(:3) .path_descend(@default.weight) as p return p{*}
ResultA --3--> E A <--6-- B <--2-- E
Analysis: Porperty @default.weight should be loaded to engine (LTE).
Filter Edge Direction
Example: Find 1~3-step paths from A to E with all edges right-pointing, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(:3) .direction(right) as p return p{*}
ResultA --3--> E
Example: Find 1~3-step paths from A to E with all edges left-pointing, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(:3) .direction(left) as p return p{*}
ResultA <--6-- B <--2-- E
Filter Circles
Example: Find 4-step paths from A to E that do not contain circle, carry all properties
UQLab().src({_id == "A"}).dest({_id == "C"}).depth(4).no_circle() as p return p{*}
ResultA <--6-- B <--2-- E --3--> D --4--> C
Analysis: Paths with circle will be returned if not using no_circle():
ResultA --3--> E --2--> B --6--> A --1--> C A <--6-- B <--2-- E --3--> D --4--> C A <--6-- B <--2-- E <--3-- A --1--> C
limit()
Example: Find a 1~3-step path from A to E, carry all properties
UQLab().src({_id == "A"}).dest({_id == "E"}).depth(:3).limit(1) as p return p{*}
ResultA <--6-- B <--2-- E