I am stuck on one query in mysql - php

Question

I am stuck on one query in mysql.
I want to fetch most recent comment from the table
the comment should be most recent comment on the blog
the blogs should be latest 3 blogs.
display comment & blog only if their status is Enabled
records should be like this
Table Structure for the table the table blog
blog_id int - primary (auto increment)
blog_title -varchar
blog_desc -varchar
blog_image -varchar
blog_tags -varchar
tot_comments -int
blog_creater -varchar
blog_create_date -datetime
blog_status -enum ('Enable','Disable')
table structure for the table blog_comment
comment_id -int (auto increment)
fk_blog_id -int
comment -varchar
comment_by -varchar
email -varchar
comment_date -datetime
comment_status -enum ('Enable','Disable')
And below is query written by me, but the result I am getting is wrong.
SELECT b.blog_title,b.blog_image, bc.*
FROM blog_comments bc, blog b
WHERE bc.comment_status='Enable'
AND b.blog_status='Enable'
AND b.blog_id=bc.fk_blog_id
GROUP BY bc.fk_blog_id
ORDER BY bc.comment_date DESC
LIMIT 0,3
Output

Answer 1

for this the easy solution will be execute 2 query for your result . first query get blog post result
$db_blog="select blog_id,blog_title from blog where blog_ststus='Enable'";
$que=mysql_query($db_blog);
while($row=mysql_fetch_object($que))
{
echo $row->blog_title;
$db_comment="select comment from blog_comments where fk_blog_id=".$row->blog_id." and comment_status='Enable' order by comment_date desc";
$quec=mysql_query($db_comment);
while($comment=mysql_fetch_object($quec))
{
echo $comment->comment;
}
}

Answer 2

Try this:
SELECT * FROM blog_comments bc, blog b
WHERE `bc.comment_status`='Enable'
AND `b.blog_status`='Enable'
AND `b.blog_id`=bc.fk_blog_id
ORDER BY `bc.comment_date` DESC LIMIT 1;
Try a simpler one:
SELECT * FROM `blog_comment` WHERE 'blog_status'='Enable' AND 'blog_id'='$blogidherefromtitle' ORDER BY 'comment_date' DESC LIMIT1

Answer 3

SELECT b.blog_title,b.blog_image, bc.*
FROM blog b
left join (
Select * from
blog_comments bc
WHERE bc.comment_status='Enable'
GROUP BY bc.fk_blog_id
having max(bc.comment_date) = bc.comment_date
) bcc on b.blog_id=bcc.fk_blog_id
where
b.blog_status='Enable'
ORDER BY b.blog_create_date desc
LIMIT 0,3
Try this one

Answer 4

try
SELECT b.blog_title,b.blog_image, bc.*
FROM blog_comments AS bc, blog AS b
WHERE bc.comment_status='Enable'
AND b.blog_status='Enable'
AND b.blog_id=bc.fk_blog_id
GROUP BY bc.fk_blog_id
ORDER BY bc.comment_date DESC
LIMIT 0,3;
(I'm not 100% sure)

Answer 5

SELECT b.blog_title,b.blog_image, bc.*
FROM blog_comments bc JOIN blog b ON bc.fk_blog_id = b.blog_id
WHERE bc.comment_status='Enable'
AND b.blog_status='Enable'
GROUP BY bc.fk_blog_id
ORDER BY bc.comment_date DESC
LIMIT 0,3

Answer 6

select b.blog_title, b.blog_image, bc.*
from blog b join
(select bc.*
from bc join (select fk_blog_id, max(comment_date) latest_date
from blog_comment
where comment_status = 'Enable'
group by fk_blog_id) latest
on bc.fk_blog_id = latest.fk_blog_id and bc.comment_date = latest_date) c
on b.blog_id = c.fk_blog_id
where b.blog_status = 'Enable'
order by c.comment_date desc
limit 0, 3
The c subquery finds the row with the latest comment for each blog, using the technique in the linked question. This is then joined with the blog table to get the appropriate blog data.

Answer 7

Try this query
SELECT
bc.*
FROM
blog AS b
INNER JOIN (SELECT id , MAX(id) AS MaxID FROM blog) AS bl ON bl.id = b.id
LEFT JOIN blog_comment AS bc ON bc.fk_blog_id = b.id
ORDER BY bc.comment_id DESC
LIMIT 3
EDITS:
SELECT
bc.*
FROM
blog AS b
INNER JOIN (SELECT id , MAX(id) AS MaxID FROM blog GROUP BY id) AS bl ON bl.id = b.id
INNER JOIN (SELECT MAX(id) , fk_blog_id FROM blog_comment GROUP BY id) AS bc ON bc.fk_blog_id = b.id
ORDER BY bc.comment_id DESC
LIMIT 3
This is for 3 latest blogs and latest single comments for each blog
Here using inner join will fetch the latest blog. than join comments and order them with date or id and limit them according to your requirements.