@jahed/sparql-engine/dist/engine/stages/aggregate-stage-builder.d.ts

SPARQL query engine for servers and web browsers.

import type { Expression, Grouping, Query } from "sparqljs";
import type { CustomFunctions } from "../../operators/expressions/sparql-expression.ts";
import type { Bindings } from "../../rdf/bindings.ts";
import ExecutionContext from "../context/execution-context.ts";
import type { PipelineStage } from "../pipeline/pipeline-engine.ts";
import StageBuilder from "./stage-builder.ts";
/**
 * An AggregateStageBuilder handles the evaluation of Aggregations operations,
 * GROUP BY and HAVING clauses in SPARQL queries.
 * @see https://www.w3.org/TR/sparql11-query/#aggregates
 */
export default class AggregateStageBuilder extends StageBuilder {
    /**
     * Build a {@link PipelineStage} for the evaluation of SPARQL aggregations
     * @param source  - Input {@link PipelineStage}
     * @param query   - Parsed SPARQL query (logical execution plan)
     * @param options - Execution options
     * @return A {@link PipelineStage} which evaluate SPARQL aggregations
     */
    execute(source: PipelineStage<Bindings>, query: Query, context: ExecutionContext, customFunctions?: CustomFunctions): Promise<PipelineStage<Bindings>>;
    /**
     * Build a {@link PipelineStage} for the evaluation of a GROUP BY clause
     * @param source  - Input {@link PipelineStage}
     * @param  groupby - GROUP BY clause
     * @param  options - Execution options
     * @return A {@link PipelineStage} which evaluate a GROUP BY clause
     */
    _executeGroupBy(source: PipelineStage<Bindings>, groupby: Grouping[], context: ExecutionContext, customFunctions?: CustomFunctions): PipelineStage<Bindings>;
    /**
     * Build a {@link PipelineStage} for the evaluation of a HAVING clause
     * @param  source  - Input {@link PipelineStage}
     * @param  having  - HAVING clause
     * @param  options - Execution options
     * @return A {@link PipelineStage} which evaluate a HAVING clause
     */
    _executeHaving(source: PipelineStage<Bindings>, having: Expression[], context: ExecutionContext, customFunctions?: CustomFunctions): PipelineStage<Bindings>;
}