storage/mozIStorageAggregateFunction.idl
author Boris Zbarsky <bzbarsky@mit.edu>
Mon, 12 Feb 2018 15:44:40 -0500
changeset 403504 91d647c847e56cb0db2be19647507cec207b1d08
parent 244595 ad01543457e739b4eee7a245e16734a3ecfd10ad
child 475219 020c8c871c0d3b3920fe95935cfef06501976c0f
permissions -rw-r--r--
Bug 1436902 part 3. Replace usage of NS_IMPL_ISUPPORTS_INHERITED0 with NS_INLINE_DECL_REFCOUNTING_INHERITED when possible. r=mccr8 The change to RootAccessible.cpp fixes an obvious bug introduced in bug 741707. The visibility changes in gfx/thebes are because NS_DECL_ISUPPORTS has a trailing "public:" that those classes were relying on to have public constructors. MozReview-Commit-ID: IeB8KIJCGhU

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"

interface mozIStorageConnection;
interface mozIStorageValueArray;
interface nsIArray;
interface nsIVariant;

/**
 * mozIStorageAggregateFunction represents aggregate SQL function.
 * Common examples of aggregate functions are SUM() and COUNT().
 *
 * An aggregate function calculates one result for a given set of data, where
 * a set of data is a group of tuples. There can be one group
 * per request or many of them, if GROUP BY clause is used or not.
 */
[scriptable, uuid(763217b7-3123-11da-918d-000347412e16)]
interface mozIStorageAggregateFunction : nsISupports {
  /**
   * onStep is called when next value should be passed to
   * a custom function.
   * 
   * @param aFunctionArguments    The arguments passed in to the function
   */
  void onStep(in mozIStorageValueArray aFunctionArguments);

  /**
   * Called when all tuples in a group have been processed and the engine
   * needs the aggregate function's value.
   *
   * @returns aggregate result as Variant.
   */
  nsIVariant onFinal();
};