Struct Exists 

pub struct Exists<D, Req> { /* private fields */ }

EXISTS (<subquery>). Not an Expr, because unlike every other expression this one is dialect-pinned: the subquery it holds was capability-checked against its own dialect, and any CTE it binds is already rendered in that dialect. It is therefore a condition and only a condition — .filter(..) it, or predicate(..) it into a collection, onto a query of the same dialect. A Predicate carries D for this reason: discharging a condition gives up the tables it named, never the dialect it was built for.

Trait Implementations

impl<D, Req> Clone for Exists<D, Req>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<D, Scope: Superset<Req, Idxs>, Req, Idxs> Condition<D, Scope, Idxs> for Exists<D, Req>