Struct datafusion::physical_expr::equivalence::EquivalenceGroup

pub struct EquivalenceGroup { /* private fields */ }

An EquivalenceGroup is a collection of EquivalenceClasses where each class represents a distinct equivalence class in a relation.

Implementations

impl EquivalenceGroup

pub fn is_empty(&self) -> bool

Checks whether this equivalence group is empty.

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

Normalizes the given physical expression according to this group. The expression is replaced with the first expression in the equivalence class it matches with (if any).

pub fn normalize_sort_expr( &self, sort_expr: PhysicalSortExpr ) -> PhysicalSortExpr

Normalizes the given sort expression according to this group. The underlying physical expression is replaced with the first expression in the equivalence class it matches with (if any). If the underlying expression does not belong to any equivalence class in this group, returns the sort expression as is.

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

Normalizes the given sort requirement according to this group. The underlying physical expression is replaced with the first expression in the equivalence class it matches with (if any). If the underlying expression does not belong to any equivalence class in this group, returns the given sort requirement as is.

pub fn normalize_exprs( &self, exprs: impl IntoIterator<Item = Arc<dyn PhysicalExpr>> ) -> Vec<Arc<dyn PhysicalExpr>>

This function applies the normalize_expr function for all expressions in exprs and returns the corresponding normalized physical expressions.

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

This function applies the normalize_sort_expr function for all sort expressions in sort_exprs and returns the corresponding normalized sort expressions.

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

This function applies the normalize_sort_requirement function for all requirements in sort_reqs and returns the corresponding normalized sort requirements.

pub fn project(&self, mapping: &ProjectionMapping) -> EquivalenceGroup

Projects this equivalence group according to the given projection mapping.

pub fn join( &self, right_equivalences: &EquivalenceGroup, join_type: &JoinType, left_size: usize, on: &[(Column, Column)] ) -> EquivalenceGroup

Combine equivalence groups of the given join children.

Trait Implementations

impl Clone for EquivalenceGroup

fn clone(&self) -> EquivalenceGroup

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for EquivalenceGroup

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

Formats the value using the given formatter.