Question

This is the task at hand: I have a db table named ‘reports’, one of the columns in this table is ‘submitted_by’. This column contains the username of the person who submitted the report.

Now, what I need to do is display a list of usernames ordered by the number of reports they’ve posted. So something like this should come out:

User | Reports

---

Mark | 25

---

John | 18

---

Mary | 7

etc.

I have written this PHP/MySQL code to do this, it’s pretty straightforward but I was wondering if these could be merged into 1 query. Also, would that gain much in terms of efficiency?

$users=array();

$result=mysql_query("select id,submitted_by from reports group by submitted_by");
while($row=mysql_fetch_array($result)){
    $result1=mysql_query("select id,submitted_by from reports where submitted_by='$row[submitted_by]' ");
    $users[$row[submitted_by]]=mysql_num_rows($result1);
}

arsort($users);

And then just echo each element from $users.

Answer 1

Try the following code:

$users = array();

$result=mysql_query("SELECT id, submitted_by, COUNT(*) as cnt FROM reports GROUP BY submitted_by ORDER BY COUNT(*) DESC");

while($row=mysql_fetch_array($result)){
    $users[$row['submitted_by']] = $row['cnt'];
}