SQL Path Functions

The following algorithms are also available as SQL functions that return a list of vertex RIDs (identities). They can be used in any SQL SELECT statement.

dijkstra() SQL Function

Property Value

Function

dijkstra()

Category

Path Finding

Complexity

CPU

Syntax

dijkstra(<sourceVertex>, <destinationVertex>, <weightEdgeFieldName> [, <direction>])
dijkstra(<sourceVertex>, <destinationVertex>, <weightEdgeFieldName>,
         { direction: <string>, edgeTypeNames: [...], maxDepth: <long>, emptyIfMaxDepth: <bool> })

Parameters

Parameter Type Required Default Description

sourceVertex

Vertex / RID

Yes

—

Source vertex

destinationVertex

Vertex / RID

Yes

—

Destination vertex

weightEdgeFieldName

String

Yes

—

Edge property name for weights

direction

String

No

"BOTH"

Traversal direction: "IN", "OUT", or "BOTH". Can also be passed as direction key in the trailing options map.

The 4th argument can also be an options map with keys direction, edgeTypeNames, maxDepth, emptyIfMaxDepth. Unknown keys are rejected with a descriptive error.

Return Value

List<RID> — Ordered list of vertex identities on the shortest path (including source and destination).

Description

SQL function equivalent of algo.dijkstra. Internally delegates to the A* implementation with no heuristic. Returns a LinkedList of vertex RIDs.

Examples

-- Positional form (backward compatible)
SELECT dijkstra(#12:0, #12:5, 'weight', 'OUT') AS path

-- Options map form
SELECT dijkstra(#12:0, #12:5, 'weight', { direction: 'OUT', maxDepth: 20 }) AS path

See also: dijkstra() in SQL Functions reference and reference/graph-algorithms/path-finding.adoc#algo-dijkstra for the Cypher procedure variant.

bellmanFord() SQL Function

Property Value

Function

bellmanFord()

Category

Path Finding

Complexity

CPU

Syntax

bellmanFord(<sourceVertex>, <destinationVertex>, <weightEdgeFieldName> [, <direction>])
bellmanFord(<sourceVertex>, <destinationVertex>, <weightEdgeFieldName>, { direction: <string> })

Parameters

Parameter Type Required Default Description

sourceVertex

Vertex / RID

Yes

—

Source vertex

destinationVertex

Vertex / RID

Yes

—

Destination vertex

weightEdgeFieldName

String

Yes

—

Edge property name for weights (may be negative)

direction

String

No

"BOTH"

Traversal direction: "IN", "OUT", or "BOTH". Can also be passed as direction key in the trailing options map.

Return Value

List<RID> — Ordered list of vertex identities on the shortest path.

Description

SQL function equivalent of algo.bellmanford. Supports negative edge weights and detects negative-weight cycles (returns an empty path if a negative cycle is reachable).

Example

SELECT bellmanFord(#12:0, #12:5, 'cost') AS path
SELECT bellmanFord(#12:0, #12:5, 'cost', { direction: 'OUT' }) AS path

See also: reference/graph-algorithms/path-finding.adoc#algo-bellman-ford for the Cypher procedure variant.

shortestPath() SQL Function

Property Value

Function

shortestPath()

Category

Path Finding

Complexity

CPU

Syntax

shortestPath(<sourceVertex>, <destinationVertex>)
shortestPath(<sourceVertex>, <destinationVertex>, <direction>, <edgeType>, { maxDepth, edge })
shortestPath(<sourceVertex>, <destinationVertex>,
             { direction: <string>, edgeType | edgeTypeNames: <string|list>, maxDepth: <int>, edge: <bool> })

Parameters

Parameter Type Required Default Description

sourceVertex

Vertex / RID

Yes

—

Source vertex

destinationVertex

Vertex / RID

Yes

—

Destination vertex

direction

String

No

"BOTH"

Traversal direction: "IN", "OUT", or "BOTH". Positional or map key.

edgeType

String / List

No

all types

Edge type(s) to restrict traversal. Positional or map key (edgeType or edgeTypeNames).

maxDepth

Int

No

unlimited

Stop after this many hops. Options-map only (or via the trailing map in the positional form).

edge

Bool

No

false

Include edge RIDs in the result. Options-map only.

The 3rd argument can be a direction string (backward compatible) OR an options map consolidating all knobs. Unknown keys are rejected with a descriptive error.

Return Value

List<RID> — Ordered list of vertex identities on the shortest path (unweighted; minimizes hop count).

Description

Finds the unweighted shortest path (minimum hop count) between two vertices using bidirectional BFS (meets in the middle), which can be significantly faster than single-direction BFS for large graphs.

Examples

-- Positional form (backward compatible)
SELECT shortestPath(#12:0, #12:9, 'BOTH', 'KNOWS') AS path

-- Options map form
SELECT shortestPath(#12:0, #12:9, { direction: 'BOTH', edgeTypeNames: ['KNOWS'], maxDepth: 6 }) AS path

References

See also: shortestPath() in SQL Functions reference.