Struct ChildFilterDescription 

pub struct ChildFilterDescription {
    pub(crate) parent_filters: Vec<PushedDownPredicate>,
    pub(crate) self_filters: Vec<Arc<dyn PhysicalExpr>>,
}

Describes filter pushdown for a single child node.

This structure contains two types of filters:

• Parent filters: Filters received from the parent node, marked as supported or unsupported
• Self filters: Filters generated by the current node to be pushed down to this child

Fields

parent_filters: Vec<PushedDownPredicate>

Description of which parent filters can be pushed down into this node. Since we need to transmit filter pushdown results back to this node’s parent we need to track each parent filter for each child, even those that are unsupported / won’t be pushed down.

self_filters: Vec<Arc<dyn PhysicalExpr>>

Description of which filters this node is pushing down to its children. Since this is not transmitted back to the parents we can have variable sized inner arrays instead of having to track supported/unsupported.

Implementations

impl ChildFilterDescription

pub fn from_child( parent_filters: &[Arc<dyn PhysicalExpr>], child: &Arc<dyn ExecutionPlan>, ) -> Result<Self>

Build a child filter description by analyzing which parent filters can be pushed to a specific child.

This method performs column analysis to determine which filters can be pushed down:

• If all columns referenced by a filter exist in the child’s schema, it can be pushed down
• Otherwise, it cannot be pushed down to that child

See FilterDescription::from_children for more details

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

Add a self filter (from the current node) to be pushed down to this child.

pub fn with_self_filters(self, filters: Vec<Arc<dyn PhysicalExpr>>) -> Self

Add multiple self filters.

Trait Implementations

impl Clone for ChildFilterDescription

fn clone(&self) -> ChildFilterDescription

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ChildFilterDescription

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

Formats the value using the given formatter.