Struct datafusion_physical_expr::equivalence::EquivalenceProperties

pub struct EquivalenceProperties { /* private fields */ }

Represents a collection of EquivalentClass (equivalences between columns in relations)

This is used to represent:

1. Equality conditions (like A=B), when T = Column

Implementations

impl EquivalenceProperties

pub fn new(schema: SchemaRef) -> Self

pub fn classes(&self) -> &[EquivalentClass<Column>]

return the set of equivalences

pub fn schema(&self) -> SchemaRef

pub fn extend<I: IntoIterator<Item = EquivalentClass<Column>>>( &mut self, iter: I )

Add the EquivalentClass from iter to this list

pub fn add_equal_conditions(&mut self, new_conditions: (&Column, &Column))

Adds new equal conditions into the EquivalenceProperties. New equal conditions usually come from equality predicates in a join/filter.

pub fn normalize_expr( &self, expr: Arc<dyn PhysicalExpr> ) -> Arc<dyn PhysicalExpr>

Normalizes physical expression according to EquivalentClasses inside self.classes. expression is replaced with EquivalentClass::head expression if it is among EquivalentClass::others.

pub fn normalize_exprs( &self, exprs: &[Arc<dyn PhysicalExpr>] ) -> Vec<Arc<dyn PhysicalExpr>>

This function applies the [normalize_expr] function for all expression in exprs and returns a vector of normalized physical expressions.

pub fn normalize_sort_requirement( &self, sort_requirement: PhysicalSortRequirement ) -> PhysicalSortRequirement

This function normalizes sort_requirement according to EquivalenceClasses in the self. If the given sort requirement doesn’t belong to equivalence set inside self, it returns sort_requirement as is.

pub fn normalize_sort_requirements( &self, sort_reqs: &[PhysicalSortRequirement] ) -> Vec<PhysicalSortRequirement>

This function applies the [normalize_sort_requirement] function for all sort requirements in sort_reqs and returns a vector of normalized sort expressions.

pub fn normalize_sort_exprs( &self, sort_exprs: &[PhysicalSortExpr] ) -> Vec<PhysicalSortExpr>

Similar to the [normalize_sort_requirements] this function normalizes sort expressions in sort_exprs and returns a vector of normalized sort expressions.

Trait Implementations

impl Clone for EquivalenceProperties

fn clone(&self) -> EquivalenceProperties

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for EquivalenceProperties

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

Formats the value using the given formatter.