How to use MediaStore query to get Artists without duplicates?

Question

I would like to get all the artists names on my phone by using MediaStore ;Already I have the whole list but with duplicates of all entries due to multiple links songs/artists. Is there any way to use the query to get only one of each, without any duplicates?

There is my query :

    String selection = MediaStore.Audio.Media.IS_MUSIC + " != 0";

    String[] projection = {
            MediaStore.Audio.Media.ALBUM,
            MediaStore.Audio.Media.ARTIST,
            MediaStore.Audio.Media.TITLE,
            MediaStore.Audio.Media.DATA,
            MediaStore.Audio.Media.DURATION
    };
    Cursor cursor = context.getContentResolver().query(
            MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,
            projection,
            selection,
            null,
            null);

Thanks in advance !

Answer 1

For people who are still looking for an answer to this, I'd suggest doing the following:

String[] mProjection =
         {
                MediaStore.Audio.Artists._ID,
                MediaStore.Audio.Artists.ARTIST,
                MediaStore.Audio.Artists.NUMBER_OF_TRACKS,
                MediaStore.Audio.Artists.NUMBER_OF_ALBUMS
         };

Cursor artistCursor = mContentResolver.query(
                MediaStore.Audio.Artists.EXTERNAL_CONTENT_URI,
                mProjection,
                null,
                null,
                MediaStore.Audio.Artists.ARTIST + " ASC");  

Now you can query this cursor to get the name of all artists. There won't be any duplicates.
I understand that this is not the solution to "get unique values from MediaStore" in general. But it would solve this very specific problem.

Explanation:
You just have to query the right table, which in this case was the "Artist" table, while the op was querying the "Media" table.

Hope this helps someone.

Answer 2

Using the keyword DISTINCT in the query returns non duplicate values For example, listing only album names when querying many audio numbers

        new String[] { "DISTINCT " + MediaStore.Audio.Playlists.Members.ALBUM_ID + " as _id"}

but I found you can only return one column

I kept it simple and did the following when looping through the cursor. Pass the value, in your case the artist,

    if (value.length() > 0) {
        // check if value already exists
        if (!listItems.contains(value)) {
            // doesn't exist, add it
            listItems.add(value);
        }

    }

This is a simple method. You can check this out in my app Playlist Manager on Google Play. I use this technique for selecting artists, years, etc.