Struct Select 

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 union_default: bool,
    pub plan: Plan,
    pub star_counter: usize,
}

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

Fields

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.

union_default: bool

Union default graph (opt-in, non-standard): when set and the query has no FROM of its own, the active default graph becomes the RDF merge of the file’s default graph and every named graph — the mode Virtuoso, GraphDB and Jena TDB (tdb:unionDefaultGraph) offer. Plain SPARQL says a pattern outside GRAPH matches only the real default graph, so this is NEVER set by the parser — only by eval_query_with when the caller asked for it. An explicit FROM wins (the query named its own dataset).

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.

Trait Implementations

impl Clone for Select

fn clone(&self) -> Select

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Select

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

Formats the value using the given formatter.

impl Default for Select

fn default() -> Select

Returns the “default value” for a type.