getting tasks starting from same date and bringing the minimum duration one task top of the list

I am making an agenda management application for android, i have calculated the duration of each tasks i am inserting, but now i want that tasks which have minimum duration and starting from same date and time shows top of the list, mean i get notification of that task first. This is my database file,please help me out, thanks.

public class SamaDb {
public static final String Row_Id = "rowId";
public static final String Task_Title = "taskTitle";

public static final String Start_Date = "startDate";
public static final String End_Date = "endDate";

public static final String Start_Time = "startTime";
public static final String End_Time = "endTime";

public static final String Description = "description";
public static final String Days_Difference = "days_difference";
public static final String Hours_Difference="hours_difference";
public static final String Minutes_Difference="minutes_difference";

private static final String myDb = "databaseName";
private static final String Table_Task = "tableName";
private static final int Version = 1;

private DbHelper helper;
private final Context ourContext;
private SQLiteDatabase ourDataBase;

private static class DbHelper extends SQLiteOpenHelper {
    public DbHelper(Context context)
    {
        super(context, myDb, null, Version);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("CREATE TABLE " + Table_Task + " (" +
                        Task_Title + " TEXT NOT NULL, " +
                        Start_Date + " TEXT NOT NULL, " +
                        End_Date + " TEXT NOT NULL, " +
                        Start_Time + " TEXT NOT NULL, " +
                        End_Time + " TEXT NOT NULL, " +
                        Description + " TEXT NOT NULL, " +
                        Days_Difference + " TEXT NOT NULL, "+
                        Hours_Difference + " TEXT NOT NULL,"+
                        Minutes_Difference + " TEXT NOT NULL);"
        );

    }
        // TEXT NOT NULL);"
    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        db.execSQL("DROP TABLE IF EXISTS " + Table_Task);
        onCreate(db);
    }
}
public SamaDb(Context c){
    ourContext=c;
}
public SamaDb Open() throws SQLException{
    helper= new DbHelper(ourContext);
    ourDataBase=helper.getWritableDatabase();
    return this;
}
public  void close(){
    helper.close();
}
public long createEntry(String str_task_title,String str_start_date, String str_end_date,
                        String str_start_time,String str_end_time,
                        String str_Task_Description,String str_days_difference,String str_hours_difference,String str_minutes_difference) {
    // TODO Auto-generated method stub
    ContentValues cv = new ContentValues();
    cv.put(Task_Title, str_task_title);
    cv.put(Start_Date, str_start_date);
    cv.put(End_Date, str_end_date);
    cv.put(Start_Time, str_start_time);
    cv.put(End_Time, str_end_time);
    cv.put(Description, str_Task_Description);
    cv.put(Days_Difference,str_days_difference);
    cv.put(Hours_Difference,str_hours_difference);
    cv.put(Minutes_Difference,str_minutes_difference);
   // cv.put(Difference, duration);
    return ourDataBase.insert(Table_Task,null,cv);
}
public String getData() {
    // TODO Auto-generated method stub
    String[] columns = new String[]{Task_Title,Start_Date,End_Date,
            Start_Time,End_Time,Days_Difference,Hours_Difference,Minutes_Difference,Description};
    Cursor c=ourDataBase.query(Table_Task,columns, null,null,null,null,Days_Difference+" DESC");
    String result = "";


    int iTitle=c.getColumnIndex(Task_Title);
    int int_start_date=c.getColumnIndex(Start_Date);
    int e_Date=c.getColumnIndex(End_Date);
    int int_start_time=c.getColumnIndex(Start_Time);
    int int_end_time=c.getColumnIndex(End_Time);
    int int_description=c.getColumnIndex(Description);
    int int_days_difference=c.getColumnIndex(Days_Difference);
    int int_hours_difference=c.getColumnIndex(Hours_Difference);
    int int_minutes_difference=c.getColumnIndex(Minutes_Difference);

    for(c.moveToFirst();!c.isAfterLast();c.moveToNext()){
                result=result + c.getString(int_description) + "\n" + c.getString(int_start_date) +
                        "      " + c.getString(int_start_time) + "\nTo  " + c.getString(e_Date) + "   " + c.getString(int_end_time)
                        +"\n " +c.getString(int_days_difference)+ " Day/s,  "+c.getString(int_hours_difference)+" Hour/s  and "
                        +c.getString(int_minutes_difference)+" Minute/s  \n"+
                         c.getString(iTitle) + "\n \n";

    }
    return result;

}

1. List item