Struct UnionEquivalentOrderingBuilder 

struct UnionEquivalentOrderingBuilder {
    orderings: Vec<LexOrdering>,
}

Builds valid output orderings of a UnionExec

Fields

orderings: Vec<LexOrdering>

Implementations

impl UnionEquivalentOrderingBuilder

fn new() -> Self

fn add_satisfied_orderings( &mut self, source: &EquivalenceProperties, properties: &EquivalenceProperties, ) -> Result<()>

Add all orderings from source that satisfy properties, potentially augmented with the constants in source.

Note: Any column that is known to be constant can be inserted into the ordering without changing its meaning.

For example:

• Orderings in source contains [a ASC, c ASC] and constants contains b,
• properties has the ordering [a ASC, b ASC].

Then this will add [a ASC, b ASC] to the orderings list (as a was in the sort order and b was a constant).

fn try_add_ordering( &mut self, ordering: LexOrdering, constants: &[ConstExpr], properties: &EquivalenceProperties, properties_constants: &[ConstExpr], ) -> Result<AddedOrdering>

Adds ordering, potentially augmented with constants, if it satisfies the given properties.

Returns

An AddedOrdering::Yes instance if the ordering was added (either directly or augmented), or was empty. An AddedOrdering::No instance otherwise.

fn try_find_augmented_ordering( &mut self, ordering: &LexOrdering, constants: &[ConstExpr], properties: &EquivalenceProperties, properties_constants: &[ConstExpr], ) -> bool

Attempts to add constants to ordering to satisfy the properties. Returns true if augmentation took place, false otherwise.

fn augment_ordering( ordering: &LexOrdering, constants: &[ConstExpr], existing_ordering: &LexOrdering, existing_constants: &[ConstExpr], ) -> Option<LexOrdering>

Attempts to augment the ordering with constants to match existing_ordering. Returns Some(ordering) if an augmented ordering was found, None otherwise.

fn build(self) -> Vec<LexOrdering>

Trait Implementations

impl Debug for UnionEquivalentOrderingBuilder

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

Formats the value using the given formatter.