mysql - Ordering by top commented -

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how list page of top commented pages on site php , mysql?

the database set sort of this:

page_id | username | comment | date_submitted --------+----------+---------+---------------       1 |  bob     | hello   | current date       1 |  joe     | byebye  | current date       4 |  joe     | stuff   | date       3 |  mark    |    | date

how query orders them top commented pages?

here simple query start (with xxx being areas think need with):

$querycomments = sprintf("select * comments " .     "xxx = %s order xxx desc",     getsqlvaluestring(????????????, "text"));

well, if you're looking way list pages in order of comments, group page id , order count, like:

select page_id, count(*) comments group page_id order 2 desc, 1 asc

technically, don't need 1 asc ensure specific order within descending comment count. so, if lot of pages identical comment count appear, can locate specific page within group easily. in other words, if page 7 had 2 comments , other pages had one, you'd (7,1,2,3,4,5,6,8,9). without 1 asc, pages 1 through 6 , 8 through 9 come in order, (7,6,2,4,3,9,1,8,5) , change between runs of query.

for example, build sample table:

> drop table comments; > create table comments (page_id integer,comment varchar(10)); > insert comments values (1,'1a'); > insert comments values (2,'2a'); > insert comments values (1,'1b'); > insert comments values (3,'3a'); > insert comments values (2,'2b'); > insert comments values (1,'1c'); > insert comments values (3,'3b'); > insert comments values (3,'3c'); > insert comments values (3,'3d');

then show data:

> select * comments   order 1, 2;     +---------+---------+     | page_id | comment |     +---------+---------+     |       1 | 1a      |     |       1 | 1b      |     |       1 | 1c      |     |       2 | 2a      |     |       2 | 2b      |     |       3 | 3a      |     |       3 | 3b      |     |       3 | 3c      |     |       3 | 3d      |     +---------+---------+

then run select group descending comment count:

> select page_id,count(*) quant   comments   group page_id   order 2 desc, 1 asc;     +---------+-------+     | page_id | quant |     +---------+-------+     |       3 |     4 |     |       1 |     3 |     |       2 |     2 |     +---------+-------+

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