Struct RecursiveQueryExec

pub struct RecursiveQueryExec { /* private fields */ }

Recursive query execution plan.

This plan has two components: a base part (the static term) and a dynamic part (the recursive term). The execution will start from the base, and as long as the previous iteration produced at least a single new row (taking care of the distinction) the recursive part will be continuously executed.

Before each execution of the dynamic part, the rows from the previous iteration will be available in a “working table” (not a real table, can be only accessed using a continuance operation).

Note that there won’t be any limit or checks applied to detect an infinite recursion, so it is up to the planner to ensure that it won’t happen.

Implementations

impl RecursiveQueryExec

pub fn try_new( name: String, static_term: Arc<dyn ExecutionPlan>, recursive_term: Arc<dyn ExecutionPlan>, is_distinct: bool, ) -> Result<Self>

Create a new RecursiveQueryExec

pub fn name(&self) -> &str

Ref to name

pub fn static_term(&self) -> &Arc<dyn ExecutionPlan>

Ref to static term

pub fn recursive_term(&self) -> &Arc<dyn ExecutionPlan>

Ref to recursive term

pub fn is_distinct(&self) -> bool

is distinct

Trait Implementations

impl Clone for RecursiveQueryExec

fn clone(&self) -> RecursiveQueryExec

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for RecursiveQueryExec

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

Formats the value using the given formatter.

impl DisplayAs for RecursiveQueryExec

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 RecursiveQueryExec

fn name(&self) -> &'static 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 properties(&self) -> &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 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 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 with_new_children( self: Arc<Self>, children: Vec<Arc<dyn ExecutionPlan>>, ) -> Result<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>, ) -> Result<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 statistics(&self) -> Result<Statistics>

👎Deprecated since 48.0.0: Use partition_statistics method instead

Returns statistics for this ExecutionPlan node. If statistics are not available, should return Statistics::new_unknown (the default), not an error.

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 schema(&self) -> SchemaRef

Get the schema for this execution plan

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

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_ordering(&self) -> Vec<Option<LexRequirement>>

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

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

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

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

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>>>

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

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

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, child_pushdown_result: ChildPushdownResult, _config: &ConfigOptions, ) -> Result<FilterPushdownPropagation<Arc<dyn ExecutionPlan>>>

Handle the result of a child pushdown. This is called as we recurse back up the plan tree after recursing down and calling ExecutionPlan::gather_filters_for_pushdown. Once we know what the result of pushing down filters into children is we ask the current node what it wants to do with that result. For a DataSourceExec that may be absorbing the filters to apply them during the scan phase (also known as late materialization). A FilterExec may absorb any filters its children could not absorb, or if there are no filters left it may remove itself from the plan altogether. It combines both ChildPushdownResult::parent_filters and ChildPushdownResult::self_filters into a single predicate and replaces it’s own predicate. Then it passes PredicateSupport::Supported for each parent predicate to the parent. A HashJoinExec may ignore the pushdown result since it needs to apply the filters as part of the join anyhow. It passes ChildPushdownResult::parent_filters back up to it’s parents wrapped in FilterPushdownPropagation::transparent and ChildPushdownResult::self_filters is discarded.