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Select

Struct Select 

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pub struct Select {
    pub project: Vec<String>,
    pub distinct: bool,
    pub offset: usize,
    pub limit: Option<usize>,
    pub group: Option<GroupSpec>,
    pub extends: Vec<(String, FExpr)>,
    pub order: Vec<(FExpr, bool)>,
    pub having: Vec<FExpr>,
    pub from: Vec<String>,
    pub from_named: Option<Vec<String>>,
    pub plan: Plan,
    pub star_counter: usize,
}
Expand description

A lowered SELECT query: solution modifiers plus the evaluation plan tree.

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§project: Vec<String>

Projected variable names (empty = SELECT *).

§distinct: bool

DISTINCT (or REDUCED) requested.

§offset: usize

OFFSET (solutions to skip).

§limit: Option<usize>

LIMIT (max solutions), if any.

§group: Option<GroupSpec>

GROUP BY + aggregates, applied after the plan and before projection.

§extends: Vec<(String, FExpr)>

BIND/aggregate-alias assignments (result_var, expr), applied after aggregation (e.g. (COUNT(?f) AS ?n) aliases an internal var to ?n).

§order: Vec<(FExpr, bool)>

ORDER BY keys (expr, descending), applied before projection/slice.

§having: Vec<FExpr>

HAVING conditions, applied after aggregation.

§from: Vec<String>

FROM <iri> graphs: when non-empty, the query’s default graph is the union (RDF merge) of these named graphs.

§from_named: Option<Vec<String>>

FROM NAMED <iri> graphs: when Some, GRAPH may only see these.

§plan: Plan

The graph-pattern evaluation plan.

§star_counter: usize

Monotonic counter for minting query-unique fresh variable names while lowering (e.g. the ?__qtN holders that desugar RDF-star quoted-triple patterns). Kept on Select so it stays unique across every BGP in one query — two joined BGPs must not both mint __qt1 and get unified.

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impl Clone for Select

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fn clone(&self) -> Select

Returns a duplicate of the value. Read more
1.0.0 (const: unstable) · Source§

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

Performs copy-assignment from source. Read more
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impl Debug for Select

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

Formats the value using the given formatter. Read more
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impl Default for Select

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fn default() -> Select

Returns the “default value” for a type. Read more

Auto Trait Implementations§

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<ST, DT> CastableFrom<ST, Initialized, Initialized> for DT
where ST: ?Sized, DT: ?Sized,

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impl<ST, DT> CastableFrom<ST, Uninit, Uninit> for DT
where ST: ?Sized, DT: ?Sized,

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impl<T> CloneToUninit for T
where T: Clone,

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unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> Read<Exclusive, BecauseExclusive> for T
where T: ?Sized,

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impl<T> Same for T

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type Output = T

Should always be Self
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impl<T> ToOwned for T
where T: Clone,

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type Owned = T

The resulting type after obtaining ownership.
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fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
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fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = !

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, !>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
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impl<V, T> VZip<V> for T
where V: MultiLane<T>,

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fn vzip(self) -> V