With a Left Join i have this result.
Here the screen
http://f.cl.ly/items/373Y141r1K131d0n3f1q/Schermata%202013-04-01%20alle%2016.51.18.png
i want to show only record once time, without repeat it, but with a left join all my records are different.
what i have to do for show once all my records?
the query.
SELECT * FROM login_users
LEFT JOIN login_users_seguaci
ON login_users.user_id = login_users_seguaci.following
WHERE name LIKE ""
AND user_id != '1'
ORDER BY data DESC
SELECT x.*, y.*
FROM login_users x
LEFT JOIN
(
SELECT a.*
FROM login_users_seguaci a
INNER JOIN
(
SELECT following, MAX(DATA) max_data
FROM login_users_seguaci
GROUP BY following
) b ON a.following = b.following AND
a.DATA = b.max_date
) y ON x.user_id = y.following
// WHERE ... your condition here ...
ORDER BY t.data DESC
Related
This is my code i am trying to left join the latest team data, not every piece of data. i have tried just using limit 1 but doesnt return anything
ORDER BY updated DESC LIMIT 1
this doesnt work
Any ideas?
$sql = "SELECT
events.id, events.time,events.status, events.home_team,events.away_team,events.league,
ht.id as home_id,ht.name as home_name,at.name as away_name,
statistics.home_goals,statistics.away_goals,statistics.time as game_time,
leagues.id as league_id,leagues.name as league_name,leagues.type as league_type,
country.name as country_name,country.logo,
hts.home_scored, ats.away_scored,
hts.home_conceeded,ats.away_conceeded,
hts.home_win,ats.away_win,
hts.home_15,ats.away_15,
hts.home_25,ats.away_25,
hts.home_btts, ats.away_btts,
hts.home_fts, ats.away_fts,
hts.home_cs, ats.away_cs,
hts.home_corners_for, ats.away_corners_for,
hts.home_corners_against, ats.away_corners_against,
hts.home_cards, ats.away_cards
FROM events
LEFT JOIN teams ht
ON ht.id = events.home_team
LEFT JOIN teams at
ON at.id = events.away_team
LEFT JOIN leagues
ON leagues.id = events.league
LEFT JOIN country
ON country.id=leagues.country
LEFT JOIN ( SELECT team,home_scored,home_conceeded,home_win,home_15,home_25,home_btts,home_fts,home_cs,home_corners_for,home_corners_against,home_cards FROM team_quick_stats ORDER BY updated DESC) hts
ON ht.id=hts.team
LEFT JOIN ( SELECT team,away_scored,away_conceeded,away_win,away_15,away_25,away_btts,away_fts,away_cs,away_corners_for,away_corners_against,away_cards FROM team_quick_stats ORDER BY updated DESC) ats
ON at.id=ats.team
LEFT JOIN statistics
ON statistics.event_id=events.id
WHERE (events.time BETWEEN $start AND $end) ORDER BY country.list_order, leagues.country ASC , leagues.id ASC, events.time ASC, home_name ASC";
Here's one way. Replace LEFT JOIN (SELECT team... etc....) ats with...
LEFT
JOIN
( SELECT x.team
, x.etc...
FROM team_quick_stats x
JOIN
( SELECT team
, MAX(updated) updated
FROM team_quick_stats
GROUP
BY team
) y
ON y.team = x.team
AND y.updated = x.updated
) ats...
Hello I am using the following query to display the count of the rows where id is the same number from first table, I have 2 more tables. If I leave only one count evertything is working fine but with double count select I am getting the same result which is wrong:
'SELECT c.*, count(s.userID) as count_consulta, count(a.userID) as count_asesoria
FROM users as c
LEFT JOIN consulta AS s ON s.userID = c.userID
LEFT JOIN asesoria AS a ON a.userID = c.userID
GROUP BY c.userID DESC'
with this I am getting:
count_consulta = 15
count_asesoria = 15
where it should be
count_consulta = 3
count_asesoria = 5
any help will be welcome. Thanks!
With the statement "any help will be welcome" I throw this out there to see if it does what you mean.
$sql="select *,
( select count( distinct s.`userID` ) from `consulta` ) as 'count_consulta',
( select count( distinct a.`userID` ) from `asesoria` ) as 'count_asesoria'
from `users` c
left outer join `consulta` s on s.`userID`=c.`userID`
left outer join `asesoria` a on a.`userID`=c.`userID`
group by c.`userID` desc;";
I have a query that LEFT JOINS another table to group rows. I am trying to only select records from the first table "googleimage" where the user_id is a certain number. (user_id is a column in "googleimage" table.
SELECT g.*
FROM googleimage g
LEFT JOIN (SELECT image_id, COUNT(*) AS cnt
FROM googleimagefound WHERE status = 0
GROUP BY image_id) gf ON gf.image_id = g.id
ORDER BY COALESCE(cnt, 0) DESC");
I have tried adding a new ON statement beiside the
gf ON gf.image_id = g.id
I have also tried changing
SELECT g.*
FROM googleimage g
to
SELECT g.*
FROM googleimage WHERE user_id = 1 g
but none of them seem to work, any help will be appriciated
Try changing you query a bit like below
SELECT g.*
FROM googleimage g
LEFT JOIN (SELECT image_id, COUNT(*) AS cnt
FROM googleimagefound WHERE status = 0
GROUP BY image_id) gf ON gf.image_id = g.id
WHERE g.user_id = 1 <-- add this condition
ORDER BY COALESCE(gf.cnt, 0) DESC;
I have a problem trying to JOIN an empty table (comments table) to my existing prepared statement.
This is working perfectly:
// prepare images
if ($stmt = $mysqli->prepare(" SELECT uu.*, m.*,
(
SELECT COUNT(*)
FROM img_likes AS t
WHERE t.img_id = uu.imgID AND t.user_id = ?
) AS user_likes,
(
SELECT COUNT(*)
FROM img_likes AS t
WHERE t.img_id = uu.imgID
) AS total_likes
FROM user_uploads AS uu
INNER JOIN members AS m ON m.id = uu.user_id
ORDER BY up_time DESC")) {
$stmt->bind_param('i', $user_id);
$stmt->execute(); // get imgs
// foreach print images
// working as expected
}
And I don't know why if I JOIN another table (img_comments) that is empty, the images are not printed... if I add a row to the table and refresh the page, one image is printed...
The statement that I'm trying and it's not working is this:
SELECT uu.*, m.*, ic.*,
(
SELECT COUNT(*)
FROM img_likes AS t
WHERE t.img_id = uu.imgID AND t.user_id = ?
) AS user_likes,
(
SELECT COUNT(*)
FROM img_likes AS t
WHERE t.img_id = uu.imgID
) AS total_likes
FROM user_uploads AS uu
INNER JOIN members AS m ON m.id = uu.user_id
INNER JOIN img_comments AS ic ON ic.img_id = uu.imgID
ORDER BY up_time DESC
Why is only printing images based on the number of the table rows?? I also tried LEFT JOIN but I'm not too familiareize with this. I only use INNER JOIN in other scripts and I never had a problem like this.
I would appreciate any optimization to my query.
What does an inner join do? It joins all records of table a with all matching records of table b. So when there are no records in table b, there is no match for any record of table a, hence no result at all. Why does this surprise you?
A left join is an outer join (short for LEFT OUTER JOIN). It means: Give me all records of table a with all matching records of table b, and when there is no match then give me the record of table a anyhow. This seems to be what you are wanting here. But you say you tried it. I don't see how this would fail in your query.
A typical error for an outer join not to work would be to have some field of b in your where clause (e.g. where b.id > 100). As the outer-joined records have no matching b record, all b fields are null, so that such a where clause would fail. You'd just get matches again, just like with the inner join.
EDIT: As to optimization, you can get the two counts in one pass by counting conditionally:
SELECT
uu.*, m.*, ic.*,
il.count_user AS user_likes,
il.count_total AS total_likes
FROM user_uploads AS uu
INNER JOIN members AS m ON m.id = uu.user_id
LEFT OUTER JOIN img_comments AS ic ON ic.img_id = uu.imgID
LEFT OUTER JOIN
(
select
img_id,
count(*) as count_total,
count(case when t.user_id = ? then 1 end) as count_user
from img_likes
group by img_id
) AS il ON il.img_id = uu.imgID
ORDER BY uu.up_time DESC;
As far as I know, INNER JOIN will only retrieve data which have both data. So if let say the table that you join have no data with that join condition. It will not return any data at all.
LEFT JOIN is just a normal join. It will retrieve data on both table. But if the joined table is empty, then only the primary table will have data, the secondary table will have null as its data.
You can just modify your code, replacing INNER JOIN with LEFT JOIN and see if it works/
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;