Struct transform::redundant_join::RedundantJoin [−][src]
pub struct RedundantJoin {
recursion_guard: RecursionGuard,
}
Expand description
Remove redundant collections of distinct elements from joins.
Fields
recursion_guard: RecursionGuard
Implementations
Remove redundant collections of distinct elements from joins.
This method tracks “provenance” information for each collections, those being column-wise relationships to identified collections (either imported collections, or let-bound collections). These relationships state that when projected on to these columns, the records of the one collection are contained in the records of the identified collection.
This provenance information is then used for the MirRelationExpr::Join
variant to remove “redundant” joins, those that can be determined to
neither restrict nor augment one of the input relations. Consult the
find_redundancy
method and its documentation for more detail.
Trait Implementations
Extracts a reference to the recursion guard embedded within the type.
fn checked_recur<F, T, E>(&self, f: F) -> Result<T, E> where
F: FnOnce(&Self) -> Result<T, E>,
E: From<RecursionLimitError>,
fn checked_recur<F, T, E>(&self, f: F) -> Result<T, E> where
F: FnOnce(&Self) -> Result<T, E>,
E: From<RecursionLimitError>,
Checks whether it is safe to recur and calls f
if so. Read more
fn checked_recur_mut<F, T, E>(&mut self, f: F) -> Result<T, E> where
F: FnOnce(&mut Self) -> Result<T, E>,
E: From<RecursionLimitError>,
fn checked_recur_mut<F, T, E>(&mut self, f: F) -> Result<T, E> where
F: FnOnce(&mut Self) -> Result<T, E>,
E: From<RecursionLimitError>,
Like CheckedRecursion::checked_recur
, but operates on a mutable
reference to Self
. Read more
Returns the “default value” for a type. Read more
fn transform(
&self,
relation: &mut MirRelationExpr,
_: TransformArgs<'_>
) -> Result<(), TransformError>
fn transform(
&self,
relation: &mut MirRelationExpr,
_: TransformArgs<'_>
) -> Result<(), TransformError>
Transform a relation into a functionally equivalent relation.
Auto Trait Implementations
impl !RefUnwindSafe for RedundantJoin
impl Send for RedundantJoin
impl !Sync for RedundantJoin
impl Unpin for RedundantJoin
impl UnwindSafe for RedundantJoin
Blanket Implementations
Mutably borrows from an owned value. Read more
Attaches the provided Subscriber
to this type, returning a
WithDispatch
wrapper. Read more
Attaches the current default Subscriber
to this type, returning a
WithDispatch
wrapper. Read more