pub type exists<Expr> = Exists<Expr>;
Expand description
The return type of exists(expr)
Aliased Type§
struct exists<Expr> {
pub subselect: Subselect<Expr, Bool>,
}
Fields§
§subselect: Subselect<Expr, Bool>
The inner subselect
Trait Implementations§
source§impl<T> Expression for Exists<T>where
Subselect<T, Bool>: Expression,
impl<T> Expression for Exists<T>where Subselect<T, Bool>: Expression,
source§impl<T, DB> QueryFragment<DB, AnsiSqlExistsSyntax> for Exists<T>where
DB: Backend + SqlDialect<ExistsSyntax = AnsiSqlExistsSyntax>,
T: QueryFragment<DB>,
impl<T, DB> QueryFragment<DB, AnsiSqlExistsSyntax> for Exists<T>where DB: Backend + SqlDialect<ExistsSyntax = AnsiSqlExistsSyntax>, T: QueryFragment<DB>,
source§fn walk_ast<'b>(&'b self, out: AstPass<'_, 'b, DB>) -> QueryResult<()>
fn walk_ast<'b>(&'b self, out: AstPass<'_, 'b, DB>) -> QueryResult<()>
Walk over this
QueryFragment
for all passes. Read moresource§fn to_sql(&self, out: &mut DB::QueryBuilder, backend: &DB) -> QueryResult<()>
fn to_sql(&self, out: &mut DB::QueryBuilder, backend: &DB) -> QueryResult<()>
Converts this
QueryFragment
to its SQL representation. Read moresource§fn collect_binds<'b>(
&'b self,
out: &mut <DB as HasBindCollector<'b>>::BindCollector,
metadata_lookup: &mut DB::MetadataLookup,
backend: &'b DB
) -> QueryResult<()>
fn collect_binds<'b>( &'b self, out: &mut <DB as HasBindCollector<'b>>::BindCollector, metadata_lookup: &mut DB::MetadataLookup, backend: &'b DB ) -> QueryResult<()>
Serializes all bind parameters in this query. Read more
source§fn is_safe_to_cache_prepared(&self, backend: &DB) -> QueryResult<bool>
fn is_safe_to_cache_prepared(&self, backend: &DB) -> QueryResult<bool>
Is this query safe to store in the prepared statement cache? Read more
source§impl<T: QueryId> QueryId for Exists<T>
impl<T: QueryId> QueryId for Exists<T>
source§impl<T, GB> ValidGrouping<GB> for Exists<T>where
Subselect<T, Bool>: ValidGrouping<GB>,
impl<T, GB> ValidGrouping<GB> for Exists<T>where Subselect<T, Bool>: ValidGrouping<GB>,
§type IsAggregate = <Subselect<T, Bool> as ValidGrouping<GB>>::IsAggregate
type IsAggregate = <Subselect<T, Bool> as ValidGrouping<GB>>::IsAggregate
Is this expression aggregate? Read more