gecko-dev/storage/mozIStorageAsyncStatement.idl

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * vim: sw=2 ts=2 sts=2 expandtab
 * 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 "mozIStorageBaseStatement.idl"

/**
 * An asynchronous SQL statement.  This differs from mozIStorageStatement by
 * only being usable for asynchronous execution.  (mozIStorageStatement can
 * be used for both synchronous and asynchronous purposes.)  This specialization
 * for asynchronous operation allows us to avoid needing to acquire
 * synchronization primitives also used by the asynchronous execution thread.
 * In contrast, mozIStorageStatement may need to acquire the primitives and
 * consequently can cause the main thread to lock for extended intervals while
 * the asynchronous thread performs some long-running operation.
 */
[scriptable, builtinclass, uuid(52e49370-3b2e-4a27-a3fc-79e20ad4056b)]
interface mozIStorageAsyncStatement : mozIStorageBaseStatement {
  /*
   * 'params' provides a magic JS helper that lets you assign parameters by
   * name.  Unlike the helper on mozIStorageStatement, you cannot enumerate
   * in order to find out what parameters are legal.
   *
   * This does not work for BLOBs.  You must use an explicit binding API for
   * that.
   *
   * example:
   *  stmt.params.foo = 1;
   *  stmt.params["bar"] = 2;
   *  let argName = "baz";
   *  stmt.params[argName] = 3;
   *
   * readonly attribute nsIMagic params;
   */
};