/**
 * @pwngh/economy-lab
 *
 * Copyright (c) Preston Neal
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE.md file in the root directory of this source tree.
 *
 * @license MIT
 */
/** The pool surface the lab uses: parameterized query, the error listener, and teardown. */
export interface PgPoolLike {
    query(text: string, values?: readonly unknown[]): Promise<{
        rows: Record<string, unknown>[];
        rowCount: number | null;
    }>;
    on(event: 'error', listener: (error: unknown) => void): unknown;
    end(): Promise<void>;
}
/** The single-connection surface, for one-shot administrative work. */
export interface PgClientLike {
    connect(): Promise<void>;
    query(text: string, values?: readonly unknown[]): Promise<{
        rows: Record<string, unknown>[];
        rowCount: number | null;
    }>;
    end(): Promise<void>;
}
export interface PgPoolConfig {
    connectionString: string;
    max?: number;
    connectionTimeoutMillis?: number;
    /** Startup parameter string (e.g. `-c search_path=...`), applied to every connection. */
    options?: string;
}
interface PgModule {
    Pool: new (config: PgPoolConfig) => PgPoolLike;
    Client: new (config: {
        connectionString: string;
    }) => PgClientLike;
}
export declare function loadPg(): Promise<PgModule>;
/**
 * Opens a pool with the error listener every consumer must attach — a dropped idle connection
 * emits 'error' on the pool, and an unlistened 'error' event would crash the process.
 */
export declare function openPgPool(config: PgPoolConfig): Promise<PgPoolLike>;
export {};