选择所有MySQL数据，按月份，年份计数记录不正常

Question

I have a database table with a list of IP addresses each with a datetime column, which in basic is something like this example:

ip_address    | date_first_viewed
192.122.42.2    2015-12-23 14:03:10
183.123.13.4    2015-12-23 02:11:10
193.311.31.6    2015-11-10 12:29:00

I am trying to select, count and group the data according to Month, Year so it would show as:

(2015, 12)  2
(2015, 11)  1

Here is my current query I am using although this isn't returning any dates whatsoever?

$sql8 = "SELECT COUNT(ip_address) as count, EXTRACT(YEAR_MONTH FROM date_first_viewed) as date
         FROM `all_website_stats`
         GROUP BY EXTRACT(YEAR_MONTH FROM date_first_viewed)";

Answer 1

Your SQL looks good. Just escape the reserved words count and date with backticks to avoid issues. To get the date in the format you want, you might try this query, which just concatenates the additional characters you want for formatting:

SELECT CONCAT('(', YEAR(date_first_viewed), ', ', MONTH(date_first_viewed), ')') FROM table;

So for your example:

SELECT COUNT(ip_address) as `count`, CONCAT('(', YEAR(date_first_viewed), ', ', MONTH(date_first_viewed), ')') as `date`
     FROM `all_website_stats` GROUP BY CONCAT('(', YEAR(date_first_viewed), ', ', MONTH(date_first_viewed), ')')";

should do it!