import { Runnable } from '../../databases/database_context';
import { SelectStatement } from '../../statements/select_statement';
export declare class SelectScalar<T> implements Runnable<T> {
    statement: SelectStatement;
    constructor(statement: SelectStatement);
    readonly clientInstruction = "scalar";
}
export declare function maximizeColumn<T>(statement: SelectStatement, max: Function): SelectScalar<T>;
export declare function minimizeColumn<T>(statement: SelectStatement, min: Function): SelectScalar<T>;
export declare function sumColumn<T>(statement: SelectStatement, sum: Function): SelectScalar<T>;
export declare function averageColumn<T>(statement: SelectStatement, average: Function): SelectScalar<T>;
export declare function countRows(statement: SelectStatement): SelectScalar<number>;