Question

I have a database that will store events. Each event has different activities. The database is made as so (I know this is not the best database design, but I am working with what was given to me) :

eventID | date       | eventname | activity
___________________________________________
0001    | 01/01/2012 | name1     | activty1
0002    | 01/01/2012 | name1     | activty2
0003    | 01/05/2012 | event2    | activty1
0004    | 01/05/2012 | event2    | activty2
0005    | 01/07/2012 | name1     | activty1

The same event can have multiple activities. The only way I can get the all records from an event (activities) is by the eventname column.

What I am trying to do is get the last 20 events with all it’s activities. Therefore I cannot simply select 20 rows (using LIMIT as this would not get me 20 events everytime as some events have 2 activities and others 10).

I cannot use SELECT DISTINCT eventname because some events have same name, on different dates. What I would need is to have a distinct eventname only if the date is different.

I’m lost for ideas.

Thanks.

Answer 1

SELECT
  *
FROM
  event
INNER JOIN
(
  SELECT   eventName, Date
  FROM     events
  GROUP BY eventName, Date
  ORDER BY Date DESC
  LIMIT    20
)
  AS last_20_events
    ON  last_20_events.eventName = events.eventName
    AND last_20_events.Date      = events.Date