/**
 * Shared constants for semantic layer implementation.
 */
import type { TimeGrain } from './types.js';
/**
 * Maps time grain to ClickHouse date truncation functions.
 */
export declare const GRAIN_FUNCTIONS: Record<TimeGrain, string>;
/**
 * The set of time grains supported by the planner. Derived from
 * {@link GRAIN_FUNCTIONS} so the two never drift apart.
 */
export declare const SUPPORTED_TIME_GRAINS: TimeGrain[];
/**
 * The filter operators accepted by semantic dataset and metric inputs.
 */
export declare const SEMANTIC_FILTER_OPERATORS: readonly ["eq", "neq", "gt", "gte", "lt", "lte", "in", "notIn", "between", "like"];
/**
 * Narrowing guard for a runtime-provided grain value.
 */
export declare function isSupportedTimeGrain(grain: unknown): grain is TimeGrain;
//# sourceMappingURL=constants.d.ts.map