Best android SQLite pattern

I've tried to find the best pattern for sqlite in my android applications, but I just find general: "How to fetch data" etc... eg.: http://ift.tt/1oalrZT

But how should I organize the files? Where should I place the queries?

I use a contract file:

public final class DatabaseContract {

public static final  int    DATABASE_VERSION   = 1;
public static final  String DATABASE_NAME      = "feed.db";
private static final String TEXT_TYPE          = " TEXT";
private static final String INT_TYPE           = " INT";
private static final String LONG_TYPE          = " LONG";
private static final String COMMA_SEP          = ", ";

// To prevent someone from accidentally instantiating the contract class,
// give it an empty constructor.
private DatabaseContract() {}

public static abstract class table_feedings implements BaseColumns {
    public static final String TABLE_NAME       = "feedings";
    public static final String FEED_START       = "feed_start";
    public static final String FEED_END         = "feed_end";
    public static final String CODE           = "code"; 
    public static final String NOTE             = "note";


    public static final String CREATE_TABLE = "CREATE TABLE " +
            TABLE_NAME + " (" +
            _ID + " INTEGER PRIMARY KEY, " +
            FEED_START + LONG_TYPE + COMMA_SEP +
            FEED_END + LONG_TYPE + COMMA_SEP +
            CODE + INT_TYPE + COMMA_SEP +
            NOTE + TEXT_TYPE + " )";

    public static final String DELETE_TABLE = "DROP TABLE IF EXISTS " + TABLE_NAME;
}

}

and a dbHelper:

public class FeedDbHelper extends SQLiteOpenHelper {
    public FeedDbHelper(Context context) {
            super(context, DatabaseContract.DATABASE_NAME, null, DatabaseContract.DATABASE_VERSION);
        }
        public void onCreate(SQLiteDatabase db) {
            db.execSQL(DatabaseContract.table_feedings.CREATE_TABLE);
        }
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            // This database is only a cache for online data, so its upgrade policy is
            // to simply to discard the data and start over
            db.execSQL(DatabaseContract.table_feedings.DELETE_TABLE);
            onCreate(db);
        }
        public void onDowngrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            onUpgrade(db, oldVersion, newVersion);
        }

But where should the queries be placed? In a "query class"? or in one of the helping classes already defined?

`ContentValues values = new ContentValues();
  values.put(DatabaseContract.table_feedings.FEED_START, feed_start);
  values.put(DatabaseContract.table_feedings.FEED_END, feed_end);
  values.put(DatabaseContract.table_feedings.CODE, code);
  values.put(DatabaseContract.table_feedings.NOTE, "");

            long newRowId;
            newRowId = db.insert(
                    DatabaseContract.table_feedings.TABLE_NAME,
                    null,
                    values);
            if(newRowId > 0)
                Log.i("Hei", "Row added to db");
            else
                Log.e("Hei", "Error when writing to DB");`