MySQL查询按月返回行数

Question

I'm trying to get counts of the number of rows in a table for the last 12 months , on a month by month basis to give 12 counts .

So far, I have this really ugly way of doing it:

SELECT (
    SELECT COUNT(i.id) FROM intrusions i, devices d WHERE i.device_id = d.id AND d.primary_owner_id = '1' AND FROM_UNIXTIME(start_time/1000) like '2014-04%',
    SELECT COUNT(i.id) FROM intrusions i, devices d WHERE i.device_id = d.id AND d.primary_owner_id = '1' AND FROM_UNIXTIME(start_time/1000) like '2014-03%',
    SELECT COUNT(i.id) FROM intrusions i, devices d WHERE i.device_id = d.id AND d.primary_owner_id = '1' AND FROM_UNIXTIME(start_time/1000) like '2014-02%',
    etc
)  

The tables are set up so 1 user can have many devices and 1 device can have many intrusions , hence the extra conditions.

The primary_owner_id and the date will be added in dynamically in PHP using prepared statements . Is there a better way to write this out which wouldn't involve so much repitition and binding 24 parameters? Any help would be appreciated

Answer 1

You should use grouping to get this. So something like this.

SELECT
    CONCAT(YEAR(FROM_UNIXTIME(start_time/1000)), '-', MONTH(FROM_UNIXTIME(start_time/1000))) AS `year_month`,
    COUNT(id) AS `count`
FROM intrusions AS i
INNER JOIN devices AS d
  ON i.device_id = d.id
WHERE d.primary_owner = ?
GROUP BY `year_month`
ORDER BY `year_month` DESC
LIMIT 12

Answer 2

You can use DATE_FORMAT to select the Year and Month, and you can use DATE_SUB to create a WHERE condition selecting items in the last month. Haven't tested this syntax but it should be close to correct.

This is along the same lines as the last answer but improves by firstly using the more succinct DATE_FORMAT and using DATE_SUB to automatically select the last 12 months

SELECT
  DATE_FORMAT(start_date, "%Y-%m") AS `month`,
  COUNT(`id`) AS `count`
FROM intrusions
INNER JOIN devices ON (intrusions.device_id = devices.id)
WHERE
  d.primary_owner_id = 1 AND
  DATE_SUB(CUR_DATE(), INTERVAL 12 MONTH) < start_date
GROUP BY month
ORDER BY month DESC