/**
 * Structural catalog snapshot + equivalence check, used by
 * `pgpm transform --check` to prove a transform is lossless: deploy the
 * original and the transformed module(s) into two scratch databases and
 * assert the resulting catalogs describe the same schema.
 *
 * The snapshot is intentionally order-insensitive per object class (objects
 * are keyed by identity and compared by definition), but column order within
 * a table IS part of the comparison — the dials pipeline preserves it.
 */
/** Minimal query surface: satisfied by pg Pool/PoolClient and test clients. */
export interface CatalogQueryable {
    query(text: string): Promise<{
        rows: any[];
    }>;
}
/** Catalog snapshot: object identity -> normalized definition. */
export interface CatalogSnapshot {
    schemas: Record<string, string>;
    tables: Record<string, string>;
    columns: Record<string, string>;
    constraints: Record<string, string>;
    indexes: Record<string, string>;
    functions: Record<string, string>;
    triggers: Record<string, string>;
    policies: Record<string, string>;
    rls: Record<string, string>;
    grants: Record<string, string>;
}
/**
 * Snapshot the user-schema surface of a database: schemas, tables, columns,
 * constraints, indexes, functions, triggers, policies, RLS flags, and table
 * grants. System schemas, `public`, and the pgpm ledger are excluded.
 */
export declare const snapshotCatalog: (db: CatalogQueryable) => Promise<CatalogSnapshot>;
/**
 * Column-order-insensitive view of a snapshot. Migrations that drop and add
 * columns can never reproduce a fresh deploy's physical column order
 * (Postgres appends), so migration-equivalence checks (`pgpm diff --verify`)
 * compare columns by name and definition only.
 */
export declare const withoutColumnOrder: (snap: CatalogSnapshot) => CatalogSnapshot;
/**
 * Compare two catalog snapshots. Returns a flat list of human-readable
 * differences; an empty list means the catalogs are structurally equivalent.
 */
export declare const diffCatalogSnapshots: (a: CatalogSnapshot, b: CatalogSnapshot) => string[];