Parse.com质疑指针值 [英] Parse.com Query on Pointer value

问题描述

我使用 Parse.com 我的Andr​​oid应用程序的数据库。

总之，我询问有指向类B.如果我查询A类，包括B类的字段A级反正有我可以通过一个字段B类具有查询过滤器和/或排序<？ / p>

我更熟悉SQL风格DB作为可以从我的描述变得明显。在解析我有邀请去参加一个游戏gameInvitees与一些元数据的人，例如，当他们被邀请和他们的RSVP状态的表。然后用游戏gameInstances一个单独的表。在gameInvitees包含一个指向游戏，他们被邀请和被邀请用户解析

我的问题是我想查询gameInvitees表，以便我能找到应邀根据游戏时间的游戏，这是在gameInstance表当前用户。

我目前的code看起来是这样的：

 日历CAL = Calendar.getInstance（）;
    cal.setTime（新的Date（））;
    cal.add（Calendar.HOUR，-1）;
    最后日期oneHourBack = cal.getTime（）;
    //获得游戏当前用户被邀请
    ParseQuery＆LT; GamePhaseInvitees＆GT; inviteeQuery = ParseQuery.getQuery（gameInvitees）;
    inviteeQuery.whereEqualTo（inviteeAccount，ParseUser.getCurrentUser（））; //当前用户邀请
    inviteeQuery.include（GameInstance）;
    // inviteeQuery.whereGreaterThanOrEqualTo（GameInstance.GameTime，oneHourBack）; //游戏是一个小时回来（但是，这不起作用）
    inviteeQuery.findInBackground（新FindCallback＆LT; GamePhaseInvitees＆GT;（）{
        公共无效完成（列表＆LT; GamePhaseInvitees＆GT; gamesInvitedToList，ParseException的E）{
            如果（E == NULL）{            }其他{
            }        }
    }）;
 

这code简化一点来解释这个问题。基本上，我需要弄清楚的东西我可以与注释掉行做在由指针连接的字段查询。那可能吗？是否有任何解决方法清洁的解决方案是什么？

解决方案

下面是一个可能的解决方案：

从表的类型创建的parseObject：的parseObject时间=新的parseObject（日期）;
然后，从结果中获得的parseObject： =时间result.getParseObject（的pointer_field）;

现在你可以从时间拉任何领域，它有就像你会做正常，例如： time.getString（some_field ）。

您可能还需要包括： query.include（的pointer_field）

I'm using Parse.com for my android apps database.

In short I'm querying class A that has a field pointing to class B. If I query class A and include class B is there anyway I can have the query filter and/or sort by a field in class B?

I'm more familiar with sql style db as may become obvious from my description. In parse I have a table for the people invited to a game "gameInvitees" with some metadata such as when they were invited and their rsvp status. Then a separate table with the games "gameInstances". The "gameInvitees" include a pointer to the game they are invited to and the parse user that is invited.

My issue is I'm trying to query the "gameInvitees" table so that I can find current users invited to a game based on the game time, which is in the "gameInstance" table.

My current code looks something like this:

    Calendar cal = Calendar.getInstance();
    cal.setTime(new Date());
    cal.add(Calendar.HOUR, -1);
    final Date oneHourBack = cal.getTime();


    // get games that the current user is invited to
    ParseQuery<GamePhaseInvitees> inviteeQuery = ParseQuery.getQuery("gameInvitees");
    inviteeQuery.whereEqualTo("inviteeAccount", ParseUser.getCurrentUser());  // current user is invited
    inviteeQuery.include("GameInstance");
    //    inviteeQuery.whereGreaterThanOrEqualTo("GameInstance.GameTime", oneHourBack);  // game is one hour back (but, this doesn't work)


    inviteeQuery.findInBackground(new FindCallback<GamePhaseInvitees>() {
        public void done(List<GamePhaseInvitees> gamesInvitedToList, ParseException e) {
            if (e == null) {

            } else {
            }

        }
    });

That code is simplified a bit to explain the problem. Basically I need to figure out something I can do with that commented out line to query on a field that is connected by a pointer. Is that possible? Are there any clean workaround solutions for that?

解决方案

Here is a possible solution:

Create a ParseObject from the type of your table: ParseObject time = new ParseObject("Date"); Then get the ParseObject from the result: time = result.getParseObject(pointer_field);

Now you can pull from time any field that it has just as you would do it normally, for example: time.getString("some_field").

You may also need to include: query.include("pointer_field").

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