Question

I am writing an android application storing workout dates and calories burned. Below is an example of the data in my table:
this is returned by:

SELECT month, day, calories FROM workouts ORDER BY year ASC, month ASC, day ASC LIMIT 12;

---

(month | day | calories)
3|2|714
3|3|945
3|4|630
3|10|446
3|16|396
3|20|255
3|22|108
3|23|112     
3|23|169
3|23|2160

the code i’ve written for the above is:

  public Cursor getLastTwelveDays(){
  Cursor c;
  String[] s = {KEY_MONTH, KEY_DAY, KEY_CALORIES};
  String order = KEY_YEAR + " ASC, " + KEY_MONTH + " ASC, " + KEY_DAY + " ASC LIMIT 12" ;
  c = db.query(WORKOUT_TABLE, s, null, null, null, null, order);
  return c;
}

I would like to combine the rows with the same day and month into a single row like so:

3|2|714
3|3|945
3|4|630
3|10|446
3|16|396
3|20|255
3|22|108
3|23|2441    (112 + 169 + 2160)    

Also, it would be nice if it were easy to use with android’s query function.

Thanks in advance.

Answer 1

What you are looking for is the group by clause. Use the SUM() method to get the total calories for each date. I believe the group by clause should go before the ORDER BY clause.

SELECT month, day, SUM(calories) FROM workouts GROUP BY month, day