Struct datafusion_physical_expr::equivalence::EquivalenceProperties

pub struct EquivalenceProperties<T = Column> { /* private fields */ }

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

This is used to represent both:

1. Equality conditions (like A=B), when T = Column
2. Ordering (like A ASC = B ASC), when T = PhysicalSortExpr

Implementations

impl<T: Eq + Clone + Hash> EquivalenceProperties<T>

pub fn new(schema: SchemaRef) -> Self

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

return the set of equivalences

pub fn schema(&self) -> SchemaRef

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

Add the EquivalentClass from iter to this list

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

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

impl EquivalenceProperties<Vec<PhysicalSortExpr, Global>>

pub fn satisfies_leading_ordering( &self, leading_ordering: &PhysicalSortExpr ) -> bool

Checks whether leading_ordering is contained in any of the ordering equivalence classes.

Trait Implementations

impl<T: Clone> Clone for EquivalenceProperties<T>

fn clone(&self) -> EquivalenceProperties<T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for EquivalenceProperties<T>

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

Formats the value using the given formatter.