Mysql query - Count items grouping by year and including "sub-counts" - mysql

Question

I have a table "events" like this
id | user_id | date | is_important
---------------------------------------------------
1 | 3 | 01/02/2012 | 0
1 | 3 | 01/02/2012 | 1
1 | 3 | 01/02/2011 | 1
1 | 3 | 01/02/2011 | 1
1 | 3 | 01/02/2011 | 0
Basically, what I need to get is this:
(for the user_id=3)
year | count | count_importants
--------------------------------------------
2012 | 2 | 1
2011 | 3 | 2
I've tried this:
SELECT YEAR(e1.date) as year,COUNT(e1.id) as count_total, aux.count_importants
FROM events e1
LEFT JOIN
(
SELECT YEAR(e2.date) as year2,COUNT(e2.id) as count_importants
FROM `events` e2
WHERE e2.user_id=18
AND e2.is_important = 1
GROUP BY year2
) AS aux ON aux.year2 = e1.year
WHERE e1.user_id=18
GROUP BY year
But mysql gives me an error
#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'aux ON aux.year2 = e1.year WHERE e1.user_id=18 GROUP BY year LIMIT 0, 30' at line 10
And i've run out of ideas to make this query u_Uº. Is it possible to do this using only one query??
Thanks in advance

Answer 1

Edit: I think I over-complicated things. Can't you just do this in a simple query?
SELECT
YEAR(`year`) AS `year`,
COUNT(`id`) AS `count`,
SUM(`is_important`) AS `count_importants`
FROM `events`
WHERE user_id = 18
GROUP BY YEAR(`year`)
Here's the big solution that adds summaries :)
Consider using MySQL GROUP BY ROLLUP. This will basically do a similar job to a normal GROUP BY, but will add rows for the summaries too.
In the example below, you see two records for Finland in 2000, for £1500 and £100, and then a row with the NULL product with the combined value of £1600. It also adds NULL rollup rows for each dimension grouped by.
From the manual:
SELECT year, country, product, SUM(profit)
FROM sales
GROUP BY year, country, product WITH ROLLUP
+------+---------+------------+-------------+
| year | country | product | SUM(profit) |
+------+---------+------------+-------------+
| 2000 | Finland | Computer | 1500 |
| 2000 | Finland | Phone | 100 |
| 2000 | Finland | NULL | 1600 |
| 2000 | India | Calculator | 150 |
| 2000 | India | Computer | 1200 |
| 2000 | India | NULL | 1350 |
| 2000 | USA | Calculator | 75 |
| 2000 | USA | Computer | 1500 |
| 2000 | USA | NULL | 1575 |
| 2000 | NULL | NULL | 4525 |
| 2001 | Finland | Phone | 10 |
| 2001 | Finland | NULL | 10 |
| 2001 | USA | Calculator | 50 |
| 2001 | USA | Computer | 2700 |
| 2001 | USA | TV | 250 |
| 2001 | USA | NULL | 3000 |
| 2001 | NULL | NULL | 3010 |
| NULL | NULL | NULL | 7535 |
+------+---------+------------+-------------+
Here's an example the specifically matches your situation:
SELECT year(`date`) AS `year`, COUNT(`id`) AS `count`, SUM(`is_important`) AS `count_importants`
FROM new_table
GROUP BY year(`date`) WITH ROLLUP;

Answer 2

The alias year - year(e1.date) AS year is not visible in JOIN ON clause. Try to use this condition -
...
LEFT JOIN
(
...
) ON aux.year2 = year(e1.date) -- e1.year --> year(e1.date)
...