Parse.com get value with query

Question

I've been looking for an example on how to use Parse.com queries. It's been really vague. I think it should start with:

ParseQuery query=ParseQuery.getQuery(<Class(aka table name)>);

But then, i've got no idea. You can do something like

query.whereEqualsTo(<collumn>,value)

In that case i get the 'value' back if it exists. What I am trying to do is. I got a table with the collumns ID and Name. I know what the ID is, it is 0. So now I want to know what Name belongs to the ID = 0.. But what query should I use, I have no idea ...

Answer 1

Parse's Android Guide has a basic query example here which will return the first object which matches your constraints:

ParseQuery<ParseObject> query = ParseQuery.getQuery("YourClassName");
query.whereEqualTo("ID", "someID");
query.getFirstInBackground(new GetCallback<ParseObject>() {
  public void done(ParseObject object, ParseException e) {
    if (object == null) {
      Log.d("score", "The getFirst request failed.");
    } else {
      Log.d("score", "Retrieved the object.");
    }
  }
});

Answer 2

我不建议使用getFirstInBackground来获取查询，使用findInBackGround然后过滤您正在寻找的值要好得多。

Answer 3

To find the list of user whose username starts with abc,You can use the condition

query.whereStartsWith("username", "abc");

So the entire query looks as

ParseQuery<ParseObject> query = ParseQuery.getQuery("YourClassName");
query.whereStartsWith("username", "abc");
query.findInBackground(new FindCallback<ParseObject>() {
  public void done(List<ParseObject> object, ParseException e) {
    if (object == null) {
      Log.d("score", "The getFirst request failed.");
    } else {
      Log.d("score", "Retrieved the object.");
    }
  }
});