Reputation: 4382
I have a problem in writing a query for MySQL. I have following fields in the DB
id created_on status
1 2011-02-15 12:47:09 1
2 2011-02-24 12:47:09 1
3 2011-02-29 12:47:09 1
4 2011-03-11 12:47:09 1
5 2011-03-15 12:47:09 1
6 2011-03-22 12:47:09 1
7 2011-04-10 12:47:09 1
8 2011-04-11 12:47:09 1
I need to select the last record of each month
.
That is for the month FEB record # 3
month MARCH record # 6
and for month APRIL record # 8
Please help me.....
Thanks in advance.....
Upvotes: 17
Views: 8490
Reputation: 654
Building off Dheer's answer:
SELECT r.*
FROM table AS r
JOIN (
SELECT MAX(t.created_on) AS created_on
FROM table AS t
GROUP BY YEAR(t.created_on), MONTH(t.created_on)
) AS x USING (created_on)
Be sure you have indexes on created_on, otherwise this query will kill your database if that table gets more than a couple hundred rows.
Upvotes: 8
Reputation: 4066
Assuming that there is only one record for the day;
SELECT * from table where created_on IN (Select MAX(created_on) FROM table
GROUP BY YEAR(created_on), MONTH(created_on) )
Upvotes: 2
Reputation: 13721
SELECT * FROM table
WHERE created_on in
(select DISTINCT max(created_on) from table
GROUP BY YEAR(created_on), MONTH(created_on))
Upvotes: 10
Reputation: 34214
You first need to group by year and month (otherwise you'd be filtering out months in other years). Use MAX() to get the greatest date for each group.
SELECT *, MAX(created_on) FROM table
GROUP BY YEAR(created_on), MONTH(created_on)
Upvotes: 2