Struct EmptyRelOps 

pub struct EmptyRelOps;

RelOps iterator which never returns any rows.

Used to compile queries with unsatisfiable bounds, like WHERE x < 5 AND x > 5.

Trait Implementations

impl Clone for EmptyRelOps

fn clone(&self) -> EmptyRelOps

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for EmptyRelOps

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

Formats the value using the given formatter.

impl<'a> RelOps<'a> for EmptyRelOps

fn next(&mut self) -> Option<RelValue<'a>>

Advances the iterator and returns the next RelValue.

fn select<P>(self, predicate: P) -> Select<Self, P>

where P: FnMut(&RelValue<'_>) -> bool, Self: Sized,

Creates an Iterator which uses a closure to determine if a [RelValueRef] should be yielded.

fn project<'b, P>( self, cols: &'b [ColExpr], extractor: P, ) -> Project<'b, Self, P>

where P: for<'c> FnMut(&[ColExpr], RelValue<'c>) -> RelValue<'c>, Self: Sized,

Creates an Iterator which uses a closure that projects to a new RelValue extracted from the current.

fn join_inner<Pred, Proj, KeyLhs, KeyRhs, Rhs>( self, with: Rhs, key_lhs: KeyLhs, key_rhs: KeyRhs, predicate: Pred, project: Proj, ) -> JoinInner<'a, Self, Rhs, KeyLhs, KeyRhs, Pred, Proj>

where Self: Sized, Pred: FnMut(&RelValue<'a>, &RelValue<'a>) -> bool, Proj: FnMut(RelValue<'a>, RelValue<'a>) -> RelValue<'a>, KeyLhs: FnMut(&RelValue<'a>) -> AlgebraicValue, KeyRhs: FnMut(&RelValue<'a>) -> AlgebraicValue, Rhs: RelOps<'a>,

Intersection between the left and the right, both (non-sorted) iterators.

fn collect_vec<T>(self, convert: impl FnMut(RelValue<'a>) -> T) -> Vec<T>

where Self: Sized,

Collect all the rows in this relation into a Vec<T> given a function RelValue<'a> -> T.

fn iter(&mut self) -> impl Iterator<Item = RelValue<'a>>

where Self: Sized,