Please I want to add another table (Comments) to this query to count the number of comments for each article.
$query = "SELECT M.id,M.j_surname,A.j_user_id,A.id,A.jart_title, A.jart_description, A.jart_createddate, COUNT(C.artid) AS count_comments FROM jt_articles A, jt_members M, jt_article_comments C where M.id = A.j_user_id AND C.artid = A.id ORDER BY A.jart_createddate DESC
update:
something like that (you dont post the scheme of the comments table)
SELECT M.id,M.j_surname,A.j_user_id,A.id,A.jart_title, A.jart_description,
A.jart_createddate , COUNT(A.id) AS count_comments
FROM jt_articles A
left join jt_members M on M.id = A.j_user_id
left join jt_article_comments C on C.artid = A.id
group by A.id
ORDER BY A.jart_createddate DESC
Related
I'm having trouble with getting the 3 latest comments from two different tables.
Here is my code, which works perfect with one inner join:
$query = mysql_query("SELECT COUNT(c.topic_id) AS ctid, COUNT(c.deck_id) AS dtid, f.id AS forumid, f.class AS forumclass, f.name AS forumname, f.url AS forumurl,
c.id AS commentid, c.user_id AS commentuser, c.user_name AS commentusername, c.date AS commentdate,
c.topic_id AS topicid, c.deck_id AS deckid
FROM ".$prefix."comment AS c
INNER JOIN ".$prefix."forum AS f
ON c.topic_id = f.id GROUP BY f.id
ORDER BY commentdate DESC LIMIT 3") or die(mysql_error());
This works fine it shows the 3 latest comments from the forum table, however I have comments in the decks table too, but when I add another JOIN to the query it just won't work anymore.
$query = mysql_query("SELECT COUNT(c.topic_id) AS ctid, COUNT(c.deck_id) AS dtid, f.id AS forumid, f.class AS forumclass, f.name AS forumname, f.url AS forumurl,
c.id AS commentid, c.user_id AS commentuser, c.user_name AS commentusername, c.date AS commentdate,
c.topic_id AS topicid, c.deck_id AS deckid, , d.id, d.url AS deckurl, d.name AS deckname
FROM ".$prefix."comment AS c
INNER JOIN ".$prefix."forum AS f
ON c.topic_id = f.id
INNER JOIN ".$prefix."decks AS d
ON c.deck_id = d.id
GROUP BY f.id ORDER BY commentdate DESC LIMIT 3") or die(mysql_error());
There's a comment table and in the comment table there is a topic_id column, which is equal to the forum table's id column and there's also a deck_id column which is equal to the decks table's id column.
Obviously that GROUP BY f.id isn't good with the two inner joins.
After this query I have while ($top = mysql_fetch_assoc($query)){ ... and then if ($top['deckid']==0) then print the topicid informations else print the deckid informations.
EDIT:
Comment table (only what is important to us now):
id, topic_id, deck_id
topic_id = forum table's id
deck_id = deck table's id
Obviously there is no comment to every forum topic.
E.g.: Forum ID 5 has 4 comments, then comment table e.g.: ID 1,2,3,4 has topic_id 4,4,4,4 and deck_id 0,0,0,0.
If there's no comment then there's nothing in the comment table. So forum ID 6 has 0 comments, then there is nothing in the comments table.
If deck ID 12 has 2 comments, then comment table e.g.: 5,6 has deck_id 12,12 and topic_id 0,0.
Forum table:
id
Deck table:
id
EDIT2: Solution (not too nice, but it works):
//count how many comments the latest 3 deck topic has
$new_comment_query = mysql_query("SELECT COUNT(c.deck_id) AS dtid, c.id, c.deck_id, c.date, d.id
FROM ".$prefix."comment AS c LEFT JOIN ".$prefix."decks AS d ON d.id = c.deck_id GROUP BY d.id ORDER BY date DESC LIMIT 3");
$new_one = mysql_fetch_array($new_comment_query);
//count how many comments the latest 3 forum topic has
$new_forum_query = mysql_query("SELECT COUNT(c.topic_id) AS ctid, c.id, c.topic_id, c.date, f.id
FROM ".$prefix."comment AS c LEFT JOIN ".$prefix."forum AS f ON f.id = c.topic_id GROUP BY f.id ORDER BY date DESC LIMIT 3");
$newer_one = mysql_fetch_array($new_forum_query);
//get all the comments
$comment_query = mysql_query("SELECT id, topic_id, deck_id, date FROM ".$prefix."comment ORDER BY date DESC LIMIT 3");
while ($comment = mysql_fetch_assoc($comment_query))
{
if($comment['topic_id']==0)
{
$deck_query = mysql_query("SELECT * FROM ".$prefix."decks WHERE id=".$comment['deck_id']);
while ($deck_comments = mysql_fetch_assoc($deck_query))
{
//print all the things!
}
}
elseif($comment['deck_id']==0)
{
$forum_query = mysql_query("SELECT * FROM ".$prefix."forum WHERE id=".$comment['topic_id']);
while ($forum_comments = mysql_fetch_assoc($forum_query))
{
//print all the things!
}
}
}
Try running this query:
SELECT * FROM
(
SELECT COUNT(c.topic_id) AS ctid, COUNT(c.deck_id) AS dtid,
f.id AS forumid, f.class AS forumclass, f.name AS forumname,
f.url AS forumurl,
c.id AS commentid, c.user_id AS commentuser, c.user_name AS commentusername,
c.date AS commentdate, c.topic_id AS topicid, c.deck_id AS deckid,
d.id, d.url AS deckurl, d.name AS deckname
FROM ".$prefix."comment AS c
INNER JOIN ".$prefix."forum AS f
ON c.topic_id = f.id
INNER JOIN ".$prefix."decks AS d
ON c.deck_id = d.id
ORDER BY commentdate DESC
) t1
GROUP BY t1.forumid
LIMIT 3
I first execute your complex JOIN without the GROUP BY which was causing problems. Then I SELECT everything from that temporary table, grouping by the forumid.
In all honesty, I'm surprised your server wasn't barfing on your first query, let alone the second, but hopefully my answer will help you out.
//count how many comments the latest 3 deck topic has
$new_comment_query = mysql_query("SELECT COUNT(c.deck_id) AS dtid, c.id, c.deck_id, c.date, d.id
FROM ".$prefix."comment AS c LEFT JOIN ".$prefix."decks AS d ON d.id = c.deck_id GROUP BY d.id ORDER BY date DESC LIMIT 3");
$new_one = mysql_fetch_array($new_comment_query);
//count how many comments the latest 3 forum topic has
$new_forum_query = mysql_query("SELECT COUNT(c.topic_id) AS ctid, c.id, c.topic_id, c.date, f.id
FROM ".$prefix."comment AS c LEFT JOIN ".$prefix."forum AS f ON f.id = c.topic_id GROUP BY f.id ORDER BY date DESC LIMIT 3");
$newer_one = mysql_fetch_array($new_forum_query);
//get all the comments
$comment_query = mysql_query("SELECT id, topic_id, deck_id, date FROM ".$prefix."comment ORDER BY date DESC LIMIT 3");
while ($comment = mysql_fetch_assoc($comment_query))
{
if($comment['topic_id']==0)
{
$deck_query = mysql_query("SELECT * FROM ".$prefix."decks WHERE id=".$comment['deck_id']);
while ($deck_comments = mysql_fetch_assoc($deck_query))
{
//print all the things!
}
}
elseif($comment['deck_id']==0)
{
$forum_query = mysql_query("SELECT * FROM ".$prefix."forum WHERE id=".$comment['topic_id']);
while ($forum_comments = mysql_fetch_assoc($forum_query))
{
//print all the things!
}
}
}
i create a web app like facebook by php and mysqli
in my app i have a table for posts , one table for likes , and one table for comments
i want to get the number of comments and likes of each post in one row with his post_id!!!
i try some querys likes this :
select `tblpost`.`post_id`, COALESCE(TCOMM.`comment_num`,0) as `c_num`, COALESCE(TLIKE.`like_num`,0) as `l_num`
from
(select `tblpost`.`post_id`, count(*) as `like_num` from `tblpost` join `tbllikes` on `tbllikes`.`post_id` = `tblpost`.`post_id` group by `tblpost`.`post_id`
) TLIKE
inner join
(select `tblpost`.`post_id`, count(*) as `comment_num` from `tblpost` join `tblcomments` on `tblcomments`.`post_id` = `tblpost`.`post_id` group by `tblpost`.`post_id`) TCOMM
on
TCOMM.`post_id` = TLIKE.`post_id`
but i don't know what's my problem
You can do count distincts with two left joins.
Something like this would work if there are fields like_id and comment_id in the tables tbllikes and tblcomments
SELECT
tblpost.post_id AS post_id,
COUNT(DISTINCT tbllikes.like_id) AS likes,
COUNT(DiSTINCT tblcomments.comment_id) AS comments
FROM tblpost
LEFT JOIN tbllikes ON tbllikes.post_id = tblpost.post_id
LEFT JOIN tblcomments on tblcomments.post_id = tblpost.post_id
GROUP BY tblpost.post_id
First, I think you can greatly simplify your query:
select l.post_id,
COALESCE(c.comment_num, 0) as c_num, COALESCE(l.like_num, 0) as l_num
from (select l.post_id, count(*) as like_num
from tbllikes l
group by l.post_id
) l inner join
(select c.post_id, count(*) as comment_num
from tblcomments c
group by c.post_id
) c
on l.post_id = c.post_id;
This will only get you posts that have both likes and comments. To get what you want, use a left join:
select p.post_id,
COALESCE(c.comment_num, 0) as c_num, COALESCE(l.like_num, 0) as l_num
from tblpost p left join
(select l.post_id, count(*) as like_num
from tbllikes l
group by l.post_id
) l
on l.post_id = p.post_id left join
(select c.post_id, count(*) as comment_num
from tblcomments c
group by c.post_id
) c
on c.post_id = p.post_id;
Okay, so I have a query below I am trying to get to work.
Basically everything works up until the inner join of the 'votes' table. What I am trying to do is order the results of this query in accordance with the number of votes each content row has in another table called votes. I know I'm not too far off from what I need to do!
Thanks in advance!!
mysql_query("
SELECT content.id, content.type, content.title, content.url, users.username
FROM content
INNER JOIN users ON content.uploaderuid = users.id
INNER JOIN votes ON votes.id = content.id
WHERE (content.type = 'pic')
ORDER BY COUNT(votes.id) DESC");
Try doing:
SELECT content.id, content.type, content.title, content.url, users.username
FROM content
INNER JOIN users ON content.uploaderuid = users.id
INNER JOIN (
SELECT id,COUNT(*) as voteCount
FROM votes
GROUP BY id
) v ON v.id = content.id
WHERE (content.type = 'pic')
ORDER BY v.voteCount DESC
When you do an INNER JOIN with votes table directly, if you have multiple occurrences of the same id, you will get a lot more rows than before you did the JOIN.
If you are only interested in the number of votes for each id, by doing a JOIN with a subquery that calculates the count of votes for each id, will leave your previous query results as they were, and lets you use the voteCount to order by it.
You could try this:
SELECT c.id, c.type, c.title, c.url, u.username, COUNT(v.id) votes
FROM content c
INNER JOIN users u ON c.uploaderuid = u.id
INNER JOIN votes v ON v.id = c.id
WHERE c.type = 'pic'
GROUP BY c.id, c.type, c.title, c.url, u.username
ORDER BY votes DESC
Here is the SQL Fiddle that demonstrates the below query:
SELECT c.id, c.type, c.title, c.url, u.username, COUNT(v.id)
FROM content AS c
INNER JOIN users AS u ON c.uploaderuid = u.id
INNER JOIN votes AS v ON v.id = c.id
WHERE c.type = 'pic'
GROUP BY c.id, c.type, c.title, c.url, u.username
ORDER BY COUNT(v.id) DESC
I have this database design:
**users_tbl**
id
username
name
**posts_tbl**
id
url
users_id *FK REFERENCE to users table*
**posts_contents_tbl**
id
posts_id *FK REFERENCE to posts table
title
description
date
views
click
isDeleted
I'm using this query
SELECT a.name,a.username,c.*
FROM users_tbl a
LEFT JOIN posts_tbl b ON a.id = b.users_id
LEFT JOIN posts_contents_tbl c ON b.id = c.posts_id
ORDER BY c.id ASC
Why I try to run this query it gives me NULL results, sample output is like this
But when I try to remove the ORDER BY c.id ASC it gives me this output:
That's not my expected result.
My expected result would be it will display the posts_contents_tbl in Ascending order at the same time it won't show some null values. Some users in my database doesn't have posts data in the posts_tbl so they should not show too.
How would I do that one? Your help would be greatly appreciated and rewarded!
Thanks!
PS: I already have thousands record in my database.
In that case, you have to use INNER JOIN instead of LEFT JOIN because you only want users with posts to show. The reason why there are Null values is because the records are based on table users_tbl and you've mentioned that some of them have no post. Right?
Try this:
SELECT a.name,
a.username,
c.*
FROM users_tbl a
INNER JOIN posts_tbl b
ON a.id = b.users_id
INNER JOIN posts_contents_tbl c
ON b.id = c.posts_id
ORDER BY c.`date` DESC
I think this is what you are looking for:
SELECT a.name,a.username,c.*
FROM users_tbl a
INNER JOIN posts_tbl b
ON a.id = b.users_id
LEFT JOIN posts_contents_tbl c
ON b.id = c.posts_id
ORDER BY IFNULL(c.id, 0) ASC;
If you really needs that posts_tbl data should not display if not available.And all data of posts_contents_tbl then you need a RIGHT JOIN and INNER JOIN .
The Query like :-
SELECT a.name,a.username,c.*
FROM users_tbl a
INNER JOIN posts_tbl b ON a.id = b.users_id
RIGHT JOIN posts_contents_tbl c ON b.id = c.posts_id
ORDER BY c.id ASC;
Hello can anybody see why this query fails?
SELECT A.idAd, A.ads_in_Cat, A.title, A.currency, A.price,
A.in_dpt, A.description, A.featured FROM ads A
LEFT JOIN featured F ON F.ad = A.idAd
INNER JOIN dept D ON D.id_dept = A.in_dpt
INNER JOIN sub_cat_ad S ON S.id_sub_cat = A.ads_in_Cat
INNER JOIN cat_ad C ON C.idCat_ad = S.from_cat_ad
ORDER BY A.featured DESC LIMIT :limit, :offset
But this one works:
SELECT *FROM ads
LEFT JOIN featured ON featured.ad = ads.idAd
INNER JOIN dept ON dept.id_dept = ads.in_dpt
INNER JOIN sub_cat_ad ON id_sub_cat = ads.ads_in_Cat
INNER JOIN cat_ad ON idCat_ad = sub_cat_ad.from_cat_ad
ORDER BY featured DESC LIMIT :limit, :offset
In the first one, I don't want all columns from the table "ads", the query returns only columns till ...FROM ads A.
If you specify to only select fields from A that's what you get: Only fields from A.
If you want fields from other tables too you have to specify them as well.
SELECT
A.idAd, A.ads_in_Cat, A.title, A.currency, A.price, A.in_dpt, A.description, A.featured,
F.*,
D.*,
S.*,
C.*
FROM ads A
LEFT JOIN featured F ON F.ad = A.idAd
INNER JOIN dept D ON D.id_dept = A.in_dpt
INNER JOIN sub_cat_ad S ON S.id_sub_cat = A.ads_in_Cat
INNER JOIN cat_ad C ON C.idCat_ad = S.from_cat_ad
ORDER BY A.featured DESC LIMIT :limit, :offset