@electric-sql/d2mini/dist/operators/topKWithFractionalIndex.d.ts

D2Mini is a minimal implementation of Differential Dataflow for performing in-memory incremental view maintenance.

import { KeyValue, PipedOperator } from '../types.js';
import { DifferenceStreamReader, DifferenceStreamWriter, UnaryOperator } from '../graph.js';
interface TopKWithFractionalIndexOptions {
    limit?: number;
    offset?: number;
}
/**
 * Operator for fractional indexed topK operations
 * This operator maintains fractional indices for sorted elements
 * and only updates indices when elements move position
 */
export declare class TopKWithFractionalIndexOperator<K, V1> extends UnaryOperator<[
    K,
    V1
], [
    K,
    [V1, string]
]> {
    #private;
    constructor(id: number, inputA: DifferenceStreamReader<[K, V1]>, output: DifferenceStreamWriter<[K, [V1, string]]>, comparator: (a: V1, b: V1) => number, options: TopKWithFractionalIndexOptions);
    run(): void;
}
/**
 * Limits the number of results based on a comparator, with optional offset.
 * This works on a keyed stream, where the key is the first element of the tuple.
 * The ordering is within a key group, i.e. elements are sorted within a key group
 * and the limit + offset is applied to that sorted group.
 * To order the entire stream, key by the same value for all elements such as null.
 *
 * Uses fractional indexing to minimize the number of changes when elements move positions.
 * Each element is assigned a fractional index that is lexicographically sortable.
 * When elements move, only the indices of the moved elements are updated, not all elements.
 *
 * @param comparator - A function that compares two elements
 * @param options - An optional object containing limit and offset properties
 * @returns A piped operator that orders the elements and limits the number of results
 */
export declare function topKWithFractionalIndex<K extends T extends KeyValue<infer K, infer _V> ? K : never, V1 extends T extends KeyValue<K, infer V> ? V : never, T>(comparator: (a: V1, b: V1) => number, options?: TopKWithFractionalIndexOptions): PipedOperator<T, KeyValue<K, [V1, string]>>;
export {};