graphrecords_query/operations/conversion/
discard_index.rs

1use crate::{
2    Bare, BareValueDomain, Explain, IndexDomain, Indexed, Operand, QueryResult,
3    element::{Pipeline, Preserving},
4    execution::EvaluationCache,
5    operations::{Apply, ElementKernel, ElementPipeline, Operation, OperationContext, Prepare},
6    optimizer::{OperationInputs, OptimizerHints, PlanIdentity, PlanInputs},
7    registry::operation_manifest,
8    traits::DiscardIndex,
9};
10use graphrecords_core::GraphRecord;
11
12#[derive(Clone, Explain, Operation, OperationInputs, OptimizerHints, PlanIdentity, PlanInputs)]
13#[operation(scope = Element)]
14#[explain(label = "DiscardIndex")]
15#[plan(optimizer_hints(commutes_with_filter, allows_limit_pushdown, empty = if_any))]
16pub struct DiscardIndexOperation;
17
18impl Prepare for DiscardIndexOperation {
19    type Prepared<'a> = ();
20
21    fn prepare<'a>(
22        &'a self,
23        _graphrecord: &'a GraphRecord,
24        _cache: &'a EvaluationCache<'a>,
25    ) -> QueryResult<Self::Prepared<'a>> {
26        Ok(())
27    }
28}
29
30impl<I: IndexDomain, V: BareValueDomain> ElementKernel<Indexed<I, V>> for DiscardIndexOperation {
31    type Emission = Preserving;
32    type OutShape = Bare<V>;
33
34    fn pipeline<'a>(
35        _graphrecord: &'a GraphRecord,
36        _prepared: Self::Prepared<'a>,
37    ) -> QueryResult<ElementPipeline<'a, Indexed<I, V>, Self>> {
38        Ok(Pipeline::unkeyed(|value| value))
39    }
40}
41
42impl<O: Apply<DiscardIndexOperation>> DiscardIndex for O {
43    type ReturnOperand = O::Output;
44
45    fn discard_index(&self) -> Self::ReturnOperand {
46        Self::ReturnOperand::new(OperationContext::new(self.clone(), DiscardIndexOperation))
47    }
48}
49
50operation_manifest! {
51    DiscardIndexOperation {
52        method: DiscardIndex::discard_index;
53        scope: element;
54
55        kernel {
56            parameters: <I: IndexDomain, V: BareValueDomain>;
57            input: Indexed<I, V>;
58            output: Bare<V>;
59            emission: Preserving;
60        }
61    }
62}
graphrecords_query/operations/conversion/discard_index.rs

graphrecords_query/operations/conversion/
discard_index.rs
