/**
 * An implementation of a Perspective Virtual Server for DuckDB.
 *
 * This import is optional, and so must be imported manually from either
 * `@perspective-dev/client/dist/esm/virtual_servers/duckdb.js` or
 * `@perspective-dev/client/src/ts/virtual_servers/duckdb.ts`, it is not
 * exported from the package root `@perspective-dev/client`
 *
 * @module
 */
import type * as perspective from "@perspective-dev/client";
import type { ColumnType } from "@perspective-dev/client/dist/esm/ts-rs/ColumnType.d.ts";
import type { ViewConfig } from "@perspective-dev/client/dist/esm/ts-rs/ViewConfig.d.ts";
import type { ViewWindow } from "@perspective-dev/client/dist/esm/ts-rs/ViewWindow.d.ts";
import type * as duckdb from "@duckdb/duckdb-wasm";
/**
 * An implementation of Perspective's Virtual Server for `@duckdb/duckdb-wasm`.
 */
export declare class DuckDBHandler implements perspective.VirtualServerHandler {
    private db;
    private sqlBuilder;
    constructor(db: duckdb.AsyncDuckDBConnection, mod?: typeof perspective);
    getFeatures(): {
        group_by: boolean;
        split_by: boolean;
        sort: boolean;
        expressions: boolean;
        group_rollup_mode: string[];
        filter_ops: {
            integer: string[];
            float: string[];
            string: string[];
            boolean: string[];
            date: string[];
            datetime: string[];
        };
        aggregates: {
            integer: string[];
            float: string[];
            string: string[];
            boolean: string[];
            date: string[];
            datetime: string[];
        };
    };
    getHostedTables(): Promise<string[]>;
    tableSchema(tableId: string, config?: ViewConfig): Promise<Record<string, perspective.ColumnType>>;
    viewColumnSize(viewId: string, config: ViewConfig): Promise<number>;
    tableSize(tableId: string): Promise<number>;
    tableMakeView(tableId: string, viewId: string, config: ViewConfig): Promise<void>;
    tableValidateExpression(tableId: string, expression: string): Promise<perspective.ColumnType>;
    viewDelete(viewId: string): Promise<void>;
    viewGetMinMax(viewId: string, columnName: string, config: ViewConfig): Promise<{
        min: {} | null;
        max: {} | null;
    }>;
    viewGetData(viewId: string, config: ViewConfig, schema: Record<string, ColumnType>, viewport: ViewWindow, dataSlice: perspective.VirtualDataSlice): Promise<void>;
}