Hi guys i am new bie to MySQL,this might be
easier to question but i am totally new for mysql.
i have two tables order and shops the Desc of two
tables look like this....
OrdersTable.
order id:
ordername:
shopnum(fk)
Shopstable*
shopname:
shopnum(pk):
i am using sub query like this,to get the shops name which have most number of orders....
like...19 xyzshop
. 13 hjjddshop
. 6 reebok shop
select shopname
from shopstable
where shopnum in
(select count(orderid) as highest ,shopnum
from orderTable
group by shopnum)
it throws error,display column should be 1,its because the subquery is returning 2 results...so how do i avoid that and get the appropriate result...help will be appreciated...:):)
It's not complaining because the subquery returns 2 results but two columns. But even if it did only return a single column, it would return 2 results and the main query would do the same.
No need for a subquery in any case:
SELECT s.shopname
FROM Shopstable s
JOIN OrdersTable o ON s.shopnum=o.shopnum
GROUP BY s.shopname
ORDER BY count(*) DESC
LIMIT 1
Use this:
select shopname
from shopstable
where shopnum in
(select shopnum
from orderTable
group by shopnum
order by count(*) DESC
limit 1)
remove count(orderid) as highest , in your query. you should only select one column in your subquery
i think you want something like this...
SELECT shopname, count(*) as highest
FROM shopstable
INNER JOIN orderTable ON (shopstable = orderTable.shopname)
GROUP BY shopstable.shopname
i think this is the result you want?
Related
I want to select which model car is involved in most accidents.
i am using the following query but i get a syntax error.
please someone tell me whats wrong..
select car.Model
from car
join car_accident_involved
on car.Car_Registration_ID = car_accident_involved.Car_Registration_ID
group by car.Model
having MAX(
select COUNT(Car_Registration_ID)
from car_accident_involved
);
You can use a simple sub query here, e.g:
select model from car
where car_registration_id =
(select car_registration_id
from car_accident_involved
group by model
order by count(car_registration_id) desc
limit 1);
HAVING is a condition statement for GROUP BY. Your query hasn't any condition in
HAVING statement,so error arises.
A for me, there is no need in subquery. Try more simple query like:
SELECT c.model,COUNT(a.car_registration_id) AS Num_of_accidents FROM car c
INNER JOIN car_accident_involved a ON c.car_registration_id=a.car_registration_id
GROUP BY c.model ORDER BY Num_of_accidents DESC LIMIT 1;
I am developing a voting system.
I am facing issue in ordering.
Basically i want to get top ranking and maximum nominee first. I used "totalUserVoted" and "totalRating" in Descending order on both condition but my query ordering "totalUserVoted".
I am expecting the result in this order.
Here is my sql query.
SELECT
(SELECT (((SUM(`design`)*4)+(SUM(`usability`)*3)+(SUM(`creativity`)*2)+(SUM(`content`))*1))/ count(`nominee_id`) / 10
FROM `sk_award_nominee_rating`
WHERE `sk_award_nominee_rating`.`nominee_id`=`sk_award_nominee`.`nominee_id`) AS totalRating,
(SELECT count(`nominee_id`)
FROM `sk_award_nominee_rating`
WHERE `sk_award_nominee_rating`.`nominee_id`=`sk_award_nominee`.`nominee_id`) AS totalUserVoted,
`sk_award_nominee`.*,
`sk_user`.`username`,
`sk_user`.`email`,
`sk_user_profile`.`f_name`,
`sk_user_profile`.`m_name`,
`sk_user_profile`.`l_name`,
`sk_user_profile`.`address`
FROM `sk_award_nominee`
LEFT JOIN `sk_user` ON `sk_user`.`user_id`=`sk_award_nominee`.`user_id`
LEFT JOIN `sk_user_profile` ON `sk_award_nominee`.`user_id`=`sk_user_profile`.`user_id`
WHERE `sk_award_nominee`.`status` = 1
AND DATE(approval_date) = '2016-02-22'
ORDER BY `totalUserVoted` DESC,
`totalRating` DESC
Something like this ?
ORDER BY totalUserVoted DESC, totalRating DESC
PHP MySQL Order by Two Columns
Doing a query on forum database. I am using this query to get thread name, poster, date etc.
(Left only thread_subject for now)
SELECT `thread_subject` FROM `fusion_posts` JOIN `fusion_threads`
ON fusion_posts.thread_id=fusion_threads.thread_id JOIN `fusion_users` ON
fusion_posts.post_author=fusion_users.user_id
GROUP BY fusion_posts.thread_id ORDER BY `post_id` DESC LIMIT 16
Basically, I also need to add something like the count below to the existing select, to count posts of each thread.
SELECT COUNT(*) AS PostCount FROM fusion_posts,fusion_threads WHERE fusion_threads.thread_id = fusion_posts.thread_id group by fusion_threads.thread_id
How could I do that?
Try this:-
SELECT `thread_subject`, COUNT(*) AS PostCount
FROM `fusion_posts` JOIN `fusion_threads`
ON fusion_posts.thread_id=fusion_threads.thread_id JOIN `fusion_users`
ON fusion_posts.post_author=fusion_users.user_id
GROUP BY fusion_posts.thread_id, `thread_subject`
ORDER BY `post_id` DESC
LIMIT 16
I was thinking a way to using one query with a subquery instead of using two seperate queries.
But turns out using a subquery is causing multiple requests for each row in result set. Is there a way to limit that count subquery result only one with in a combined query ?
SELECT `ad_general`.`id`,
( SELECT count(`ad_general`.`id`) AS count
FROM (`ad_general`)
WHERE `city` = 708 ) AS count,
FROM (`ad_general`)
WHERE `ad_general`.`city` = '708'
ORDER BY `ad_general`.`id` DESC
LIMIT 15
May be using a join can solve the problem but dunno how ?
SELECT ad_general.id, stats.cnt
FROM ad_general
JOIN (
SELECT count(*) as cnt
FROM ad_general
WHERE city = 708
) AS stats
WHERE ad_general.city = 708
ORDER BY ad_general.id DESC
LIMIT 15;
The explicit table names aren't required, but are used both for clarity and maintainability (the explicit table names will prevent any imbiguities should the schema for ad_general or the generated table ever change).
You can self-join (join the table to itself table) and apply aggregate function to the second.
SELECT `adgen`.`id`, COUNT(`adgen_count`.`id`) AS `count`
FROM `ad_general` AS `adgen`
JOIN `ad_general` AS `adgen_count` ON `adgen_count`.city = 708
WHERE `adgen`.`city` = 708
GROUP BY `adgen`.`id`
ORDER BY `adgen`.`id` DESC
LIMIT 15
However, it's impossible to say what the appropriate grouping is without knowing the structure of the table.
I need display results from two joined tables only for the latest project. I have the following query:
SELECT project.id,
project.created,
COUNT(DISTINCT events.user_id) AS cnt
FROM project
JOIN events ON (events.project_id = project.id)
WHERE project.creator = $creatorID
AND events.user_id != $creatorID
ORDER BY project.created DESC
LIMIT 1
For some reason I keep on getting the first project... What am I missing here?
You're definitely on the right track. It seems you're missing a GROUP BY clause for your aggregate COUNT(). Try this:
SELECT
project.id,
project.created,
count(DISTINCT events.user_id) AS cnt
FROM project
JOIN events ON (events.project_id = project.id)
WHERE
project.creator = $creatorID
AND events.user_id != $creatorID
GROUP BY project.id, project.created
ORDER BY project.created DESC,
LIMIT 1