i want to use JOIN categories c ON c.id = i.category if post_type is 1 and i want to have c.title AS category_name, in SELECT otherwise JOIN categories c ON c.id = i.category and c.title AS category_name, must be not worked in query , i'm using case for join but my sql command is not correct. please help me. in all description my quastion means is how to change this below command to if post_type is 1 join must be not work
SELECT SQL_CALC_FOUND_ROWS
i. * ,
c.title AS category_name,
s.title AS status_title,
i.thumb_image,
CONCAT( u.name, ' ', u.family ) AS author
FROM contents i
LEFT JOIN categories c
ON i.category = CASE post_type WHEN 1 then c.id END
JOIN users u ON u.id = i.posted_by
JOIN status_topics s ON s.id = i.t_status
WHERE i.id = 2
I would always do the LEFT JOIN and put a condition on the column itself:
SELECT SQL_CALC_FOUND_ROWS
i. * ,
IF(i.post_type = 1, c.title, NULL) AS category_name,
s.title AS status_title,
i.thumb_image,
CONCAT( u.name, ' ', u.family ) AS author
FROM contents i
LEFT JOIN categories c ON i.category = c.id
JOIN users u ON u.id = i.posted_by
JOIN status_topics s ON s.id = i.t_status
WHERE i.id = 2
Related
Here is my SQL query which joins 4 tables and it works correctly.
SELECT pl.lms_id, u.id, REPLACE(trim(u.`url`), 'www.', '') AS url, trim(u.`name`) as name, p.date_removed, p.status, p.ignore_status FROM `adl_seo_status` p INNER JOIN `adl_user_profiles` u on p.profile_id = u.id INNER JOIN adl_tw_profile_acc_type ac on p.profile_id = ac.profile_id LEFT JOIN `adl_lms_prof_list` pl on u.id = pl.profile_id WHERE u.`vpg_id`='2' AND u.`status` = 'Y' and ac.acc_type_id = '2' ORDER BY u.`url` ASC, p.id DESC
I am facing an issue that, the table adl_seo_status has multiple entries for a single profile_id. So, that accounts are repeating in my listing. I want that account as a single row which means the distinct value of accounts based on profile_id.
You need to use group by, for example:
SELECT
pl.lms_id,
u.id,
REPLACE(trim(u.`url`), 'www.', '') AS url,
trim(u.`name`) AS name,
p.date_removed,
p.status,
p.ignore_status
FROM `adl_seo_status` p INNER JOIN `adl_user_profiles` u ON p.profile_id = u.id
INNER JOIN adl_tw_profile_acc_type ac ON p.profile_id = ac.profile_id
LEFT JOIN `adl_lms_prof_list` pl ON u.id = pl.profile_id
WHERE u.`vpg_id` = '2' AND u.`status` = 'Y' AND ac.acc_type_id = '2'
ORDER BY u.`url` ASC, p.id DESC GROUP BY p.profile_id;
Hello i have a query that selects products from a database, but for some reason it returns duplicates. The problem is in my joins i guess since in the product table there is no duplicate product. Here is my query:
$stmt=$dbh->prepare("SELECT
p.name,
p.slug,
p.id_product,
p.price,
pig.image,
c1.slug as ssubcat,
c2.slug as subcat,
c3.slug as cat
FROM
tbl_products p
INNER JOIN tbl_products_to_categories ptoc
ON ptoc.id_product = p.id_product
INNER JOIN tbl_catalog_categories c1
ON ptoc.id_category = c1.id_category
LEFT JOIN tbl_catalog_categories c2
ON c1.id_parent = c2.id_category
LEFT JOIN tbl_catalog_categories c3
ON c2.id_parent = c3.id_category
INNER JOIN tbl_products_images_gallery pig
ON pig.id_product = p.id_product
WHERE (c1.slug = :slug OR c2.slug = :slug OR c3.slug = :slug )
AND p.active = 1
AND p.quantity = 1
ORDER BY p.name ASC
LIMIT $start, $row_limit");
SELECT posts, its last 3 comments and count of all comments
My code:
SELECT p.*, u.id, u.username username, u.usersurname usersurname, u.usermainphoto userphoto, GROUP_CONCAT(c.text SEPARATOR 'a!k#h#md%o^v&') commenttext,GROUP_CONCAT(c.likes SEPARATOR '-') commentlikes,GROUP_CONCAT(c.dislikes SEPARATOR '-') commentdislikes, GROUP_CONCAT(c.commentdate) commentdate, GROUP_CONCAT(u2.username) commentauthorname, GROUP_CONCAT(c.anonim) commentanonym, GROUP_CONCAT(c.id) commentid, GROUP_CONCAT(u2.id) commentauthorid, GROUP_CONCAT(u2.usersurname) commentauthorsurname, GROUP_CONCAT(u2.usermainphoto) commentauthorphoto, GROUP_CONCAT(c.commentphotoid) commentphotoid
FROM posts p
LEFT JOIN comments c ON c.post = p.postid AND c.commentdel=0
LEFT JOIN users u ON u.id = p.postauthorid
LEFT JOIN users u2 ON u2.id = c.author
WHERE p.postwallid = :id AND p.postdel=0
GROUP BY postid
ORDER BY postid DESC
it gives me all comments, but I need only 3
You need a timestamp or counter of something to determine which comments are the three you want. Add that column name between the angle brackets below.
SELECT p.*, u.id, u.username username, u.usersurname usersurname, u.usermainphoto userphoto, GROUP_CONCAT(c.text SEPARATOR 'a!k#h#md%o^v&') commenttext,GROUP_CONCAT(c.likes SEPARATOR '-') commentlikes,GROUP_CONCAT(c.dislikes SEPARATOR '-') commentdislikes, GROUP_CONCAT(c.commentdate) commentdate, GROUP_CONCAT(u2.username) commentauthorname, GROUP_CONCAT(c.anonim) commentanonym, GROUP_CONCAT(c.id) commentid, GROUP_CONCAT(u2.id) commentauthorid, GROUP_CONCAT(u2.usersurname) commentauthorsurname, GROUP_CONCAT(u2.usermainphoto) commentauthorphoto, GROUP_CONCAT(c.commentphotoid) commentphotoid
FROM posts p
LEFT JOIN comments c ON c.post = p.postid AND c.commentdel = 0
LEFT JOIN users u ON u.id = p.postauthorid
LEFT JOIN users u2 ON u2.id = c.author
WHERE p.postwallid = :id AND p.postdel = 0
and (
select count(*) from comments as c2
where c2.postid = p.postid and c2.commentdel = 0
and c2.<timestamp> <= c.timestamp
) < 3
GROUP BY postid
ORDER BY postid DESC
Edit: I didn't add the count of all comments. I think you can easily add it with another subquery in the select list but I know MySQL people don't like subqueries very much.
(
select count(*) from comments as c2
where c2.postid = c.postid and c2.commentdel = 0
) as comment_count
I add in SELECT count(postid) as all_comments and at the end LIMIT 0, 3
SELECT count(postid) as all_comments, p.*, u.id, u.username username, u.usersurname usersurname, u.usermainphoto userphoto, GROUP_CONCAT(c.text SEPARATOR 'a!k#h#md%o^v&') commenttext,GROUP_CONCAT(c.likes SEPARATOR '-') commentlikes,GROUP_CONCAT(c.dislikes SEPARATOR '-') commentdislikes, GROUP_CONCAT(c.commentdate) commentdate, GROUP_CONCAT(u2.username) commentauthorname, GROUP_CONCAT(c.anonim) commentanonym, GROUP_CONCAT(c.id) commentid, GROUP_CONCAT(u2.id) commentauthorid, GROUP_CONCAT(u2.usersurname) commentauthorsurname, GROUP_CONCAT(u2.usermainphoto) commentauthorphoto, GROUP_CONCAT(c.commentphotoid) commentphotoid
FROM posts p
LEFT JOIN comments c ON c.post = p.postid AND c.commentdel=0
LEFT JOIN users u ON u.id = p.postauthorid
LEFT JOIN users u2 ON u2.id = c.author
WHERE p.postwallid = :id AND p.postdel=0
GROUP BY postid
ORDER BY postid DESC
LIMIT 0, 3
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;
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