Question

I want to make a summary script, for example, how many new users are there today, yesterday, this week, last week, this month, last month, so on.

I’m using CodeIgniter, so I wonder which one is better? Using multiple calls on models like this :

$this->model->get_today_users();
$this->model->get_yesterday_users();
$this->model->get_this_week_users();
// so on

Each one of the functions above only return the number of users with specific date range (e.g. SELECT COUNT(*) WHERE join_date=NOW() for today_users , etc – of course using CI active record ).

Or is it better having one single query with all necessary subqueries like this :

function stats(){
$this->db->select('*');
$this->db->select('(SELECT COUNT(*) FROM users WHERE join_date=NOW()) as today');
$this->db->select('(SELECT COUNT(*) FROM users WHERE join_date=NOW()-INTERVAL 1 DAY) as yesterday');
$this->db->select('(SELECT COUNT(*) FROM users WHERE WEEK(join_date)=WEEK(NOW()) ) as this_week');
$this->db->select('(SELECT COUNT(*) FROM users WHERE WEEK(join_date)=WEEK(NOW())-1 ) as last_week');
$this->db->select('(SELECT COUNT(*) FROM users WHERE MONTH(join_date)=MONTH(NOW()) ) as this_month');
$this->db->select('(SELECT COUNT(*) FROM users WHERE MONTH(join_date)=MONTH(NOW())-1 ) as last_month');
$this->db->from('users');
$ret = $this->db->get();
}

and then calling for example $data[‘stat’] = $this->model->stats(); so in views, I can call $stat->today, $stat->this_week, etc.

Thanks in advance for the answers.

UPDATE : What if I want to make a function that receives a date? Let’s say I have to loop a month like this:

//for the sake of simplicity
foreach(day in a month as $r){
    $this->model->get_user_on_this_day($r);
}

This means for a 30-day month, it will loop 30 times! Is there any better way than that?

Answer 1

IMO, neither of the approach is optimized.
Using least query is the best, so, you should do a GROUP BY query like below :

select date_format(join_date, '%Y-%m-%d') as the_date, count(*) as total
from users
where join_date between $start AND $end   <-- the date range
group by the_date;

Once you have the result, which you can set an array using date as key,
then you can further group by day, week, month…(whatever you want)

---

Seems like OP don’t understand how this work :-

The above query is doing a one-time query, and will return the rows like

2011-12-09, 20 users join
2011-12-08, 10 users join
2011-12-07, 51 users join
...

All you have to do is to iterate the results (not active record)

$query = $this->db->query($sql, array($start, $end));
$rtn   = array();
$total = 0;
foreach ($query->result() as $row)
{
  $rtn[$row->the_date] = $row->total;
  $total += $row->total;
}

By the end of the loop, $total = total user registered from $start until $end.

Is more effective and optimize then doing 30 (or 31) queries during the loop of month-day.