MySQL Inner Join Get Last Item of Joined Table

Question

There are two tables:

Table name: ticket

+-------+---------+---------+-------------------+
|  id   |  title       |  closed    | param     |
+-------+--------------+------------+-----------+
| 1     | test1        | 0          | 1         |
| 2     | test2        | 1          | 1         |
| 3     | test3        | 0          | 1         |

Table name: ticket_event

+-------+---------+---------+-----------------+
|  id   |  ticket_id   |  event   | date      |
+-------+--------------+----------+-----------+
| 1     | 1            | OPENED   |           |
| 2     | 1            | CLOSED   |           |
| 3     | 2            | OPENED   |           |
+-------+--------------+----------+-----------+

I need to get the last record of ticket_event for each ticket. Result should be:

test1 CLOSED
test2 OPENED
test3 NULL

I tried this code but I get all records for ticket_event:

SELECT t1.title as t1Title, t2.event as t2Event FROM ticket t1 LEFT JOIN ticket_event t2 ON t1.id = t2.ticket_id

Answer 1

You can join ticket to a query that returns the last event::

SELECT t.title, e.event
FROM ticket t LEFT JOIN (
  SELECT e.* from ticket_event e
  WHERE NOT EXISTS (
    SELECT 1 FROM ticket_event 
    WHERE ticket_id = e.ticket_id AND id > e.id
  )
) e 
ON t.id = e.ticket_id

See the demo.
Results:

| title | event  |
| ----- | ------ |
| test1 | CLOSED |
| test2 | OPENED |
| test3 |        |