i want to get the number of occures in another Table in MySQL.
My current Query looks like following:
SELECT
teilnehmer.`name`,
teilnehmer.`status`
FROM
teilnehmer
INNER JOIN chat ON chat.cid = teilnehmer.id
INNER JOIN videos ON videos.tid = teilnehmer.id
GROUP BY
chat.id,
videos.tid
I want now the amount of teilnehmer.id's in chat.cid's and the amount of teilehmer.id's in videos.tid's
How can i do that?
Seems like you want this:
SELECT teilnehmer.`name`,
teilnehmer.`status`,
c.ChatCount,
v.VideoCount
FROM teilnehmer
INNER JOIN
(
select count(cid) ChatCount, cid
from chat
group by cid
) c
ON c.cid = teilnehmer.id
INNER JOIN
(
select count(tid) VideoCount, tid
from videos
group by tid
) v
ON v.tid = teilnehmer.id
Related
Following query shows the results I need from table pointsList (latest records per user grouped by column idMatch)
select * from pointsList p
inner join ( select idMatch, max(datePointsCalculated ) as MaxDate from pointsList group by idMatch ) tm
on p.idMatch = tm.idMatch and p.datePointsCalculated = tm.MaxDate
order by p.idMatch ASC
But now I want to also select some additional information about the user (from table users). My naive way to tackle this was by making a new inner join like this:
select * from pointsList p, users u
inner join users
on u.idUser = p.idUser
inner join ( select idMatch, max(datePointsCalculated ) as MaxDate from pointsList group by idMatch ) tm
on p.idMatch = tm.idMatch and p.datePointsCalculated = tm.MaxDate
order by p.idMatch ASC
But I get the error message "unknown column 'p.idUser' in on clause". I tried using users.idUser and pointsList.idUser and other combinations (renaming pointsList in the on-clouse) but I always get the unknown column error (pointsList.idUser really does exist). Anyone could explain what I am doing wrong? I would like to extend this query to another table as well.
Thank you in advance!
Comma , priority in FROM clause is less than JOIN priority. And your query acts as:
select * from pointsList p,
(
users u
inner join users
on u.idUser = p.idUser
inner join ( select idMatch, max(datePointsCalculated ) as MaxDate from pointsList group by idMatch ) tm
on p.idMatch = tm.idMatch and p.datePointsCalculated = tm.MaxDate
)
order by p.idMatch ASC
Of course, table pointsList AS p is not accessible within the parenthesis.
Use CROSS JOIN instead of comma:
select * from pointsList p
CROSS JOIN users u
inner join users
on u.idUser = p.idUser
inner join ( select idMatch, max(datePointsCalculated ) as MaxDate from pointsList group by idMatch ) tm
on p.idMatch = tm.idMatch and p.datePointsCalculated = tm.MaxDate
order by p.idMatch ASC
I have a rating system in my app. Now I'm trying to get all AVG results from the ratings. Every AVG result has a result (in text) that I need to grab from the rating_results table.
It looks like this:
select round(avg(rating_results.rating)) as ratingresult, count(*) as votes, score.question_nl,
(select result_nl from rating_results where rating_results.rating = ratingresult and rating_results.score_id = score.id) from score
inner join score_categories on score_categories.id = score.category_id
inner join rating ON score.id = rating.score_id
inner join rating_results on rating.rating_result_id = rating_results.id
inner join dog on dog.id = rating.ratable_id
where dog.breed_id = 201
group by score.question_nl
The problem I have is that I cannot use ratingresult in the subselect.
Query 1 ERROR: Reference 'ratingresult' not supported (reference to
group function)
I already tried a lot but can't figure out another way.
Could use some help here, thanks!
--EDIT
The rating result explains the rating. So if the AVG rating is 4 then in the rating_results table I can find what that rating means:
Instead of a select for column value you could use a subquery for avg in join
select t.ratingresult
, count(*) as votes
, score.question_nl
, rating_results.result_nl
FROM score
inner join score_categories on score_categories.id = score.category_id
inner join rating ON score.id = rating.score_id
inner join rating_results on rating.rating_result_id = rating_results.id
inner join dog on dog.id = rating.ratable_id
INNER JOIN (
select round(avg(rating_results.rating)) as ratingresult
, score.question_nl
from score
inner join rating ON score.id = rating.score_id
inner join rating_results on rating.rating_result_id = rating_results.id
group by score.question_nl
) t ON t.ratingresult = rating_results.rating
AND rating_results.score_id = score.id
AND score.question_nl = t.question_nl
where dog.breed_id = 201
group by score.question_nl, t.ratingresult
avoinding subquery
I´m trying to make a query listing all clients, and also get the last comment and
the date of that comment inside the table of history_client inside a single query for it to be listed.
select a.id_client,a.name,a.lastname,(select b.date_created,b.comentary
from history_of_client b where a.id_client = b.id_client_asociate) from clients_main_table
You could use an inner join on max(date_created) for id_client on history table and join
SELECT a.id_client,a.name,a.lastname, h.commentary
FROM clients_main_table a
INNER join (
select b.id_client_asociate, max(b.date_created) max_date
from history_of_client
group by b.id_client_asociate ) t on t.id_client_asociate = a.id_client
INNER JOIN history_of_client h on h.id_client_asociate = t.id_client_asociate
and h.date_created = t.max_date
Use the LEFT JOIN and INNER join to get your desired result set.
select a.id_client,
a.name,
a.lastname,
hc.date_created,
hc.comentary
from clients_main_table c
left join (select id_client_asociate,max(date_created) dt from history_of_client group by id_client_asociate) h
on (c.id_client = b.id_client_asociate)
inner join history_of_client hc
on (hc.id_client_asociate = b.id_client_asociate and hc.date_created = h.date_created)
i have these tables :
notice
id INT
cdate DATETIME
...
theme
id
name
notice_theme
id_notice
id_theme
I want to get the latest notices for each theme.
SELECT id_theme, n.id
FROM notice_theme
LEFT JOIN (
SELECT id, cdate
FROM notice
ORDER BY cdate DESC
) AS n ON notice_theme.id_notice = n.id
GROUP BY id_theme
The result is not good. An idea ? Thanks.
There are so many ways to solve this but I'm used to do it this way. An extra subquery is needed to separately calculate the latest cDate for every ID.
SELECT a.*, c.*
FROM theme a
INNER JOIN notice_theme b
ON a.ID = b.id_theme
INNER JOIN notice c
ON b.id_notice = c.ID
INNER JOIN
(
SELECT a.id_theme, MAX(b.DATE_CREATE) max_date
FROM notice_theme a
INNER JOIN notice b
ON a.ID_Notice = b.ID
GROUP BY a.id_theme
) d ON b.id_theme = d.id_theme AND
c.DATE_CREATE = d.max_date
SQLFiddle Demo
I would like to get the data from one table, and count all results from other table, depending on the first table data, here is what I tried:
SELECT
cars.*, (
SELECT
COUNT(*)
FROM
uploads
WHERE
uploads.cid = cars.customer
) AS `count`,
FROM
`cars`
WHERE
customer = 11;
I dont really have an idea why its not working, as I'm not a regular MySQL user/coder...
Could anyone direct me in the right direction with this one?
SELECT
c.*, COUNT(u.cid) AS count
FROM
cars c
LEFT JOIN
uploads u
ON
u.cid=c.customer
WHERE
u.customer = 11;
GROUP BY c.cid
Try it by joining both tables using LEFT JOIN
SELECT a.customer, COUNT(b.cid) totalCount
FROM cars a
LEFT JOIN uploads b
ON a.customer = b.cid
WHERE a.customer = 11
GROUP BY a.customer
using COUNT(*) in LEFT JOIN will have records to have a minimum count of 1.
SELECT cars.*,COUNT(uploads.*) as uplloaded
from cars
left outer join uploads on uploads.cid = cars.customer
where cars.customer = 11
group by uploads.cid;
Try this :
SELECT customer, COUNT(cid) totalCount
FROM cars
INNER JOIN uploads
ON (customer = cid)
WHERE customer = 11
GROUP BY customer