Struct GraphScanExec 

pub struct GraphScanExec { /* private fields */ }

Graph scan execution plan.

Scans vertices or edges from storage with property materialization. This wraps the underlying Lance table scan with MVCC resolution and property loading.

Example

// Create a scan for Person vertices with name and age properties
let scan = GraphScanExec::new(
    graph_ctx,
    "Person",
    "n",
    vec!["name".to_string(), "age".to_string()],
    None, // No filter
);

let stream = scan.execute(0, task_ctx)?;
// Stream yields batches with columns: _vid, n.name, n.age

Implementations

impl GraphScanExec

pub fn with_vid_list_filter(self, vids: Vec<u64>) -> Self

Attach a multi-VID IN-list filter to this scan, pushing _vid IN (v1, v2, ...) to Lance at execute time. Use this for pre-resolved vid sets (e.g. from UNWIND $list AS e WHERE id(x)=e.field). See issue #55 PR #4.

pub fn with_extra_lance_filter(self, filter: String) -> Self

Attach a pre-rendered Lance filter string for indexed-property pushdown. AND-combined with any VID filter at scan time. See issue #57.

pub fn with_extra_runtime_filter(self, filter: Arc<dyn PhysicalExpr>) -> Self

Attach the Arrow-side counterpart of extra_lance_filter. Applied to the merged (Lance + L0) batch so the scan output is index-bound even for not-yet-flushed L0 rows. See issue #57.

pub fn has_extra_lance_filter(&self) -> bool

Whether this scan has an extra Lance filter pushed in. Used by the EXPLAIN/IndexUsage path to confirm the planner actually pushed.

impl GraphScanExec

pub fn new_vertex_scan( graph_ctx: Arc<GraphExecutionContext>, label: impl Into<String>, variable: impl Into<String>, projected_properties: Vec<String>, filter: Option<Arc<dyn PhysicalExpr>>, ) -> Self

Create a new graph scan for vertices.

Scans all vertices of the given label from storage and L0 buffers, then materializes the requested properties.

pub fn new_schemaless_vertex_scan( graph_ctx: Arc<GraphExecutionContext>, label_name: impl Into<String>, variable: impl Into<String>, projected_properties: Vec<String>, filter: Option<Arc<dyn PhysicalExpr>>, ) -> Self

Create a new schemaless vertex scan.

Scans the main vertices table for vertices with the given label name. Properties are extracted from props_json (all treated as Utf8/JSON). This is used for labels that aren’t in the schema.

pub fn new_multi_label_vertex_scan( graph_ctx: Arc<GraphExecutionContext>, labels: Vec<String>, variable: impl Into<String>, projected_properties: Vec<String>, filter: Option<Arc<dyn PhysicalExpr>>, ) -> Self

Create a new multi-label vertex scan using the main vertices table.

Scans for vertices that have ALL specified labels (intersection semantics). Properties are extracted from props_json (schemaless).

pub fn new_schemaless_all_scan( graph_ctx: Arc<GraphExecutionContext>, variable: impl Into<String>, projected_properties: Vec<String>, filter: Option<Arc<dyn PhysicalExpr>>, ) -> Self

Create a new schemaless scan for all vertices.

Scans the main vertices table for all vertices regardless of label. Properties are extracted from props_json with types resolved from the schema. This is used for MATCH (n) without label filter.

pub fn new_edge_scan( graph_ctx: Arc<GraphExecutionContext>, edge_type: impl Into<String>, variable: impl Into<String>, projected_properties: Vec<String>, filter: Option<Arc<dyn PhysicalExpr>>, ) -> Self

Create a new graph scan for edges.

Scans all edges of the given type from storage and L0 buffers, then materializes the requested properties.

Trait Implementations

impl Debug for GraphScanExec

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl DisplayAs for GraphScanExec

fn fmt_as(&self, _t: DisplayFormatType, f: &mut Formatter<'_>) -> Result

Format according to DisplayFormatType, used when verbose representation looks different from the default one

impl ExecutionPlan for GraphScanExec

fn name(&self) -> &str

Short name for the ExecutionPlan, such as ‘DataSourceExec’.

fn as_any(&self) -> &dyn Any

Returns the execution plan as Any so that it can be downcast to a specific implementation.

fn schema(&self) -> SchemaRef

Get the schema for this execution plan

fn properties(&self) -> &Arc<PlanProperties>

Return properties of the output of the ExecutionPlan, such as output ordering(s), partitioning information etc.

fn children(&self) -> Vec<&Arc<dyn ExecutionPlan>>

Get a list of children ExecutionPlans that act as inputs to this plan. The returned list will be empty for leaf nodes such as scans, will contain a single value for unary nodes, or two values for binary nodes (such as joins).

fn with_new_children( self: Arc<Self>, children: Vec<Arc<dyn ExecutionPlan>>, ) -> DFResult<Arc<dyn ExecutionPlan>>

Returns a new ExecutionPlan where all existing children were replaced by the children, in order

fn execute( &self, partition: usize, _context: Arc<TaskContext>, ) -> DFResult<SendableRecordBatchStream>

Begin execution of partition, returning a Stream of RecordBatches.

fn metrics(&self) -> Option<MetricsSet>

Return a snapshot of the set of Metrics for this ExecutionPlan. If no Metrics are available, return None.

fn static_name() -> &'static str

where Self: Sized,

Short name for the ExecutionPlan, such as ‘DataSourceExec’. Like name but can be called without an instance.

fn check_invariants(&self, check: InvariantLevel) -> Result<(), DataFusionError>

Returns an error if this individual node does not conform to its invariants. These invariants are typically only checked in debug mode.

fn required_input_distribution(&self) -> Vec<Distribution>

Specifies the data distribution requirements for all the children for this ExecutionPlan, By default it’s [Distribution::UnspecifiedDistribution] for each child,

fn required_input_ordering(&self) -> Vec<Option<OrderingRequirements>>

Specifies the ordering required for all of the children of this ExecutionPlan.

fn maintains_input_order(&self) -> Vec<bool>

Returns false if this ExecutionPlan’s implementation may reorder rows within or between partitions.

fn benefits_from_input_partitioning(&self) -> Vec<bool>

Specifies whether the ExecutionPlan benefits from increased parallelization at its input for each child.

fn reset_state( self: Arc<Self>, ) -> Result<Arc<dyn ExecutionPlan>, DataFusionError>

Reset any internal state within this ExecutionPlan.

fn repartitioned( &self, _target_partitions: usize, _config: &ConfigOptions, ) -> Result<Option<Arc<dyn ExecutionPlan>>, DataFusionError>

If supported, attempt to increase the partitioning of this ExecutionPlan to produce target_partitions partitions.

fn partition_statistics( &self, partition: Option<usize>, ) -> Result<Statistics, DataFusionError>

Returns statistics for a specific partition of this ExecutionPlan node. If statistics are not available, should return Statistics::new_unknown (the default), not an error. If partition is None, it returns statistics for the entire plan.

fn supports_limit_pushdown(&self) -> bool

Returns true if a limit can be safely pushed down through this ExecutionPlan node.

fn with_fetch(&self, _limit: Option<usize>) -> Option<Arc<dyn ExecutionPlan>>

Returns a fetching variant of this ExecutionPlan node, if it supports fetch limits. Returns None otherwise.

fn fetch(&self) -> Option<usize>

Gets the fetch count for the operator, None means there is no fetch.

fn cardinality_effect(&self) -> CardinalityEffect

Gets the effect on cardinality, if known

fn try_swapping_with_projection( &self, _projection: &ProjectionExec, ) -> Result<Option<Arc<dyn ExecutionPlan>>, DataFusionError>

Attempts to push down the given projection into the input of this ExecutionPlan.

fn gather_filters_for_pushdown( &self, _phase: FilterPushdownPhase, parent_filters: Vec<Arc<dyn PhysicalExpr>>, _config: &ConfigOptions, ) -> Result<FilterDescription, DataFusionError>

Collect filters that this node can push down to its children. Filters that are being pushed down from parents are passed in, and the node may generate additional filters to push down. For example, given the plan FilterExec -> HashJoinExec -> DataSourceExec, what will happen is that we recurse down the plan calling ExecutionPlan::gather_filters_for_pushdown:

fn handle_child_pushdown_result( &self, _phase: FilterPushdownPhase, child_pushdown_result: ChildPushdownResult, _config: &ConfigOptions, ) -> Result<FilterPushdownPropagation<Arc<dyn ExecutionPlan>>, DataFusionError>

Handle the result of a child pushdown.

fn with_new_state( &self, _state: Arc<dyn Any + Sync + Send>, ) -> Option<Arc<dyn ExecutionPlan>>

Injects arbitrary run-time state into this execution plan, returning a new plan instance that incorporates that state if it is relevant to the concrete node implementation.

fn try_pushdown_sort( &self, _order: &[PhysicalSortExpr], ) -> Result<SortOrderPushdownResult<Arc<dyn ExecutionPlan>>, DataFusionError>

Try to push down sort ordering requirements to this node.

fn with_preserve_order( &self, _preserve_order: bool, ) -> Option<Arc<dyn ExecutionPlan>>

Returns a variant of this ExecutionPlan that is aware of order-sensitivity.