Struct DistancePredicate 

pub struct DistancePredicate {
    pub left: Arc<dyn PhysicalExpr>,
    pub right: Arc<dyn PhysicalExpr>,
    pub distance: Arc<dyn PhysicalExpr>,
    pub distance_side: JoinSide,
}

Distance-based spatial join predicate.

This predicate represents a spatial join condition based on distance between geometries. It is used to find pairs of geometries from left and right tables where the distance between them is less than a specified threshold.

Example SQL

SELECT * FROM left_table l JOIN right_table r
ON ST_Distance(l.geom, r.geom) < 100.0

Fields

• left - Expression to evaluate the left side geometry
• right - Expression to evaluate the right side geometry
• distance - Expression to evaluate the distance threshold
• distance_side - Which side the distance expression belongs to (for column references)

Fields

left: Arc<dyn PhysicalExpr>

The expression for evaluating the geometry value on the left side. The expression should be evaluated directly on the left side batches.

right: Arc<dyn PhysicalExpr>

The expression for evaluating the geometry value on the right side. The expression should be evaluated directly on the right side batches.

distance: Arc<dyn PhysicalExpr>

The expression for evaluating the distance value. The expression should be evaluated directly on the left or right side batches according to distance_side.

distance_side: JoinSide

The side of the distance expression. It could be JoinSide::None if the distance expression is not a column reference. The most common case is that the distance expression is a literal value.

Implementations

impl DistancePredicate

pub fn new( left: Arc<dyn PhysicalExpr>, right: Arc<dyn PhysicalExpr>, distance: Arc<dyn PhysicalExpr>, distance_side: JoinSide, ) -> Self

Creates a new distance predicate.

Arguments

• left - Expression for the left side geometry
• right - Expression for the right side geometry
• distance - Expression for the distance threshold
• distance_side - Which side (Left, Right, or None) the distance expression belongs to

Trait Implementations

impl Clone for DistancePredicate

fn clone(&self) -> DistancePredicate

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DistancePredicate

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

Formats the value using the given formatter.

impl Display for DistancePredicate

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

Formats the value using the given formatter.

impl SpatialPredicateTrait for DistancePredicate

fn swap_for_swapped_children(&self) -> Self

Returns a semantically equivalent predicate after the join children are swapped.

fn update_for_child_projections( &self, projected_left_exprs: &[ProjectionExpr], projected_right_exprs: &[ProjectionExpr], ) -> Result<Option<Self>>

Rewrites the predicate to reference projected child expressions.