import { TTableSchema } from '../../thrift/TCLIService_types';
/**
 * Backend-neutral result-format taxonomy. Mirrors the three on-wire shapes
 * `ThriftOperationBackend` actually dispatches on (`COLUMN_BASED_SET`,
 * `ARROW_BASED_SET`, `URL_BASED_SET`); a kernel implementer surfaces the same
 * three so result-handling stays format-agnostic.
 */
export declare enum ResultFormat {
    ColumnBased = "COLUMN_BASED",
    ArrowBased = "ARROW_BASED",
    UrlBased = "URL_BASED"
}
/**
 * Neutral result-set metadata returned by `IOperationBackend.getResultMetadata()`.
 *
 * `schema` keeps the Thrift `TTableSchema` shape for now because the public
 * `DBSQLOperation.getSchema()` and `getMetadata()` already expose it on
 * `IOperation`; carrying it across the boundary preserves back-compat. The
 * kernel backend will adapt its column descriptors into the same shape until
 * the public IOperation surface is migrated in a later PR.
 */
export interface ResultMetadata {
    /** Column schema; null if the operation has no result set. */
    schema?: TTableSchema;
    /** Wire format the result handler should dispatch on. */
    resultFormat: ResultFormat;
    /** Whether the result payload is LZ4-compressed. */
    lz4Compressed?: boolean;
    /** Optional Arrow IPC schema bytes (for ARROW_BASED / URL_BASED formats). */
    arrowSchema?: Buffer;
    /** True iff the operation is a staging (PUT/GET/REMOVE) operation. */
    isStagingOperation: boolean;
}