PHP stack multiple values into one value - php

Question

This is the bookings table I'm using for my query
+----------------------+
| event_id | person_id |
+----------------------+
| 5 | 7 |
| 4 | 7 |
| 3 | 7 |
| 4 | 5 |
| 3 | 5 |
| 5 | 3 |
+----------------------+
This table shows that person_id 7 has 3 bookings, 5 has 2 bookings and 3 has 6 bookings.
Currently, I'm using this query to get the total number of bookings per person.
$query='
SELECT
bookings.person_id,
COUNT(bookings.person_id) AS total,
bookings.event_id,
users.display_name
FROM bookings
INNER JOIN users ON bookings.person_id=users.id
WHERE users.id=bookings.person_id
GROUP BY bookings.person_id';
$result = mysql_query($query);
if($result) {
while($row = mysql_fetch_array($result))
{
/* total bookings per user */
$value = $row['total'];
$sum += $value;
/* events booked per user */
$events....
/* Displaying results */
echo "<tr width='500'>";
echo "<td>".$row['person_id']."</td>";
echo "<td>".$row['display_name']."</td>";
echo "<td>".$row['total']."</td>";
echo "<td>".$events."</td>";
echo "</tr>";
}
This works okay and gives me:
+-----------------------------------+
| ID | NAME | Total Bookings |
+-----------------------------------+
| 7 | Bob | 3 |
| 5 | Jane | 2 |
| 3 | Joe | 1 |
+-----------------------------------+
I'm seeking help to get this to display the events booked by each person (like the 4th columns below):
+------------------------------------------------+
| ID | NAME | Total Bookings | Event IDs |
+------------------------------------------------+
| 7 | Bob | 3 | 5,4,3 |
| 5 | Jane | 2 | 4,3 |
| 3 | Joe | 1 | 5 |
+------------------------------------------------+
Could you please help me getting there.
Thanks.

Answer 1

GROUP_CONCAT https://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
$query='
SELECT
bookings.person_id,
COUNT(bookings.person_id) AS total,
GROUP_CONCAT(bookings.event_id) as event_ids,
users.display_name
FROM bookings
INNER JOIN users ON bookings.person_id=users.id
WHERE users.id=bookings.person_id
GROUP BY bookings.person_id';

Answer 2

A bit different query but same result:
SELECT
bookings.person_id,
COUNT(
bookings.person_id
) AS total,
users.display_name,
GROUP_CONCAT(
bookings.event_id
ORDER BY
bookings.event_id
) AS events_list
FROM
bookings,
users
WHERE
bookings.person_id=users.id
GROUP BY
bookings.person_id
ORDER BY
bookings.person_id
I don't know if for a large data, the execution time is less, more or equal.