import type { DatasetData, RawSeries, RowValue } from "../../../metabase-types/api";
/**
 * Sums two metric column values.
 *
 * @param left - A value to sum.
 * @param right - A value to sum.
 * @returns The sum of the two values unless both values are not numbers.
 */
export declare const sumMetric: (left: RowValue, right: RowValue) => number | null;
/**
 * Groups dataset rows by specified columns and sums metric columns.
 *
 * @param data - The rows and columns from a dataset to group.
 * @param byColumns - The column name or an array of column names to group by.
 * @returns A new dataset with grouped rows and summed metric values.
 */
export declare const groupDatasetMetrics: (data: DatasetData, byColumns: string | string[]) => DatasetData;
export declare const groupRawSeriesMetrics: (rawSeries: RawSeries, byColumns?: string | string[]) => RawSeries;
