Struct mentat_query_projector::ConstantProjector

pub struct ConstantProjector { /* fields omitted */ }

A projector that produces a QueryResult containing fixed data. Takes a boxed function that should return an empty result set of the desired type.

Methods

impl ConstantProjector

pub fn new(     spec: Rc<FindSpec>,     results_factory: Box<Fn() -> QueryResults> ) -> ConstantProjector

pub fn project_without_rows<'stmt>(&self) -> Result<QueryOutput>

Trait Implementations

impl Projector for ConstantProjector

fn project<'stmt, 's>(     &self,     _schema: &Schema,     _sqlite: &'s Connection,     _rows: Rows<'stmt> ) -> Result<QueryOutput>

fn columns<'s>(&'s self) -> Box<Iterator<Item = &Element> + 's>