Struct Query 

pub struct Query<'s, 'db, S: Schema, Shape: SelectedShape<S>> { /* private fields */ }

One persistent, reusable singular-shape query lineage.

Each authoring method returns a new lineage and leaves its ancestor usable.

Implementations

impl<'s, 'db, S: Schema, Shape: SelectedShape<S>> Query<'s, 'db, S, Shape>

pub fn close(&self)

Explicitly close this immutable query handle.

Closing is idempotent and affects only this handle. Clones, ancestors, descendants, siblings, and the authoring session have independent query lifecycles.

pub fn is_closed(&self) -> bool

Return whether this query handle was explicitly closed.

pub fn match_<M: ThingModel<Schema = S>, Mode: SelectionMode>( &self, binding: Binding<S, M, Mode>, ) -> Result<Self>

Attach one generated binding for predicates without selecting it.

pub fn where_(&self, predicate: Predicate<S>) -> Result<Self>

Attach one predicate; repeated calls form a conjunction in call order.

pub fn where_all( &self, predicates: impl IntoIterator<Item = Predicate<S>>, ) -> Result<Self>

Attach predicates as one implicit conjunction in source order.

pub fn allow_cross_join<L: Selectable<S>, R: Selectable<S>>( &self, left: L, right: R, ) -> Result<Self>

Explicitly permit one topology-level cross join between two attached generated bindings. The returned lineage is immutable and reusable.

impl<'s, 'db, S, Shape> Query<'s, 'db, S, Shape>

where S: Schema, Shape: SingularSelectedShape<S>,

pub async fn one(&self) -> Result<Shape::Output>

Return exactly one distinct selected identity, failing no_result on an empty stream and not_unique on more than one.

pub async fn rows(&self, options: RowsOptions<S>) -> Result<Vec<Shape::Output>>

Return a resource-bounded ordered sequence of distinct selected identities; the limit must be nonzero.

pub async fn first(&self, order: Order<S>) -> Result<Option<Shape::Output>>

Return the first distinct selected identity under a stable order.

impl<'s, 'db, S: Schema, Shape: SelectedShape<S>> Query<'s, 'db, S, Shape>

pub async fn page_by<R: Selectable<S>>( &self, root: R, options: PageOptions<S>, ) -> Result<Page<Shape::Output>>

Return one resource-bounded page grouped by distinct root identity.

pub async fn count_by<R: Selectable<S>>(&self, root: R) -> Result<u64>

Count distinct identities of one selected root binding.

pub async fn exists_by<R: Selectable<S>>(&self, root: R) -> Result<bool>

Test whether any distinct identity of one selected root binding exists.

impl<'s, 'db, S: Schema, B: Selectable<S>> Query<'s, 'db, S, B>

pub async fn count(&self) -> Result<u64>

Count distinct selected identities.

pub async fn exists(&self) -> Result<bool>

Test whether any distinct selected identity exists.

pub async fn aggregate<T: AggregateTuple<S>>( &self, terms: T, ) -> Result<T::Output>

Reduce the distinct selected stream to one typed tuple of aggregate values.

pub fn group_by<G: Selectable<S>>( &self, group: G, ) -> Result<GroupedQuery<'s, 'db, S, B, G>>

Group the distinct selected stream by another attached binding’s distinct identities before aggregating.

pub fn group_by_field<Owner, V>( &self, group: BoundField<S, Owner, V>, ) -> Result<FieldGroupedQuery<'s, 'db, S, B, Owner, V>>

where Owner: Model<Schema = S>, V: GroupedQueryValue,

Group the distinct selected stream by each witnessed value of one generated owned field before aggregating.

pub fn group_by_fields<G>( &self, groups: G, ) -> Result<FieldTupleGroupedQuery<'s, 'db, S, B, G>>

where G: FieldGroupTuple<S>,

Group the distinct selected stream by the Cartesian tuple of multiple generated owned fields’ witnessed values before aggregating.

Trait Implementations

impl<'s, 'db, S: Schema, Shape: SelectedShape<S>> Clone for Query<'s, 'db, S, Shape>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.