import type { Pool } from 'pg';
/**
 * Merges an array of label names with the label names of the default labels into a new array.
 * @param labelNames array of label names to merge with the default labels
 * @param defaultLabels default labels to merge with
 * @returns array of merged label names
 */
export declare function mergeLabelNamesWithStandardLabels(labelNames: string[], defaultLabels?: {}): string[];
/**
 * Merges Labels with default labels
 * @param labels labels to merge with the default labels
 * @param defaultLabels default labels to merge with
 * @returns merged labels
 */
export declare function mergeLabelsWithStandardLabels(labels: Record<string, string | number | undefined>, defaultLabels?: {}): Record<string, string | number>;
/**
 * Tries to determine the max pool size from the pool via direct property access as the configuration is not exported
 * @param pool the pool from which to get the property
 * @returns the configured max pool size or undefined
 */
export declare function getMaxPoolSize(pool: Pool): number | undefined;
/**
 * Tries to determine the host configuration from the pool via direct property access as the configuration is not exported
 * @param pool the pool from which to get the property
 * @returns the configured host or undefined
 */
export declare function getHost(pool: Pool): string | undefined;
/**
 * Tries to determine the port configuration from the pool via direct property access as the configuration is not exported
 * @param pool the pool from which to get the property
 * @returns the configured port or 5432 if not set
 * @see https://node-postgres.com/api/pool#pool-connection-parameters
 */
export declare function getPort(pool: Pool): number;
/**
 * Tries to determine the database configuration from the pool via direct property access as the configuration is not exported
 * @param pool the pool from which to get the property
 * @returns the configured database or undefined
 */
export declare function getDatabase(pool: Pool): string | undefined;