I have a database table containing game entries:
--------------------------------------------------------
| game_id | title | description | entry_time |
--------------------------------------------------------
| 1 | Game 1 | Descript... | yyyy-mm-dd hh:mm:ss |
--------------------------------------------------------
| 2 | Game 2 | Descript... | yyyy-mm-dd hh:mm:ss |
--------------------------------------------------------
And another containing game play history:
-----------------------------------------------
| game_id | user_id | entry_time |
-----------------------------------------------
| 1 | 0da89sadf89 | yyyy-mm-dd hh:mm:ss |
-----------------------------------------------
| 1 | f8jsf89vjs9 | yyyy-mm-dd hh:mm:ss |
-----------------------------------------------
| 2 | f8jsf89vjs9 | yyyy-mm-dd hh:mm:ss |
-----------------------------------------------
I am trying to select results from the first table, based on game popularity.
SELECT games.game_id, games.title, games.description
FROM `games`
JOIN foo_db.game_plays game_plays
ON game_plays.game_id LIKE games.game_id
WHERE games.title LIKE "%game%"
ORDER BY COUNT(game_plays.game_id) DESC, games.entry_time DESC
LIMIT 10
But for some reason, only one result is returned ("Game 1").
When I remove JOIN, and just order the results by entry_time, both results are returned as expected.
I made this query. Could you please try this.
SELECT a.game_id, a.title, a.description, b.total
from games a
JOIN (SELECT game_id, count(user_id) as total from
game_play group by game_id) b
ON a.game_id = b.game_id
AND a.title LIKE '%Game%'
ORDER BY b.total DESC, a.entry time DESC
OUTPUT
Hope it will help.
Because MySQL is sometimes really slow when mixing JOIN and GROUP BY, a corelated subquery might be a good alternative:
SELECT games.game_id, games.title, games.description
FROM `games`
WHERE games.title LIKE "%game%"
ORDER BY (
SELECT COUNT(game_plays.game_id)
FROM foo_db.game_plays
WHERE game_plays.game_id = games.game_id
) DESC, games.entry_time DESC
LIMIT 10
Related
It's been asked before, but I can't get it to work properly. The selected answer doesn't work with duplicate values. The second answer should be able to handle duplicates according to the poster, but it's not functioning correctly with my data.
What I want to achieve is pretty simple:
I have a database containing all scores of all users. I want to build a highscore table, so I want to select all highscore rows of each user. With highscore row I mean the row for that user where his score is the highest.
Here's a demo I made based on the answer I mentioned at the top:
CREATE TABLE test(
score INTEGER,
user_id INTEGER,
info INTEGER
);
insert into test(score, user_id, info)
values
(1000, 1, 1),
(1000, 1, 2),
(2000, 2, 3),
(2001, 2, 1);
--
SELECT t.*
FROM test t
JOIN (SELECT test.user_id, max(score) as mi FROM test GROUP BY user_id) j ON
t.score = j.mi AND
t.user_id = j.user_id
ORDER BY score DESC, info ASC;
Expected output:
+-------+---------+------+
| score | user_id | info |
+-------+---------+------+
| 2001 | 2 | 1 |
| 1000 | 1 | 1 |
+-------+---------+------+
--> every user_id is present with the row where the user had the highest score value.
Real output:
+-------+---------+------+
| score | user_id | info |
+-------+---------+------+
| 2001 | 2 | 1 |
| 1000 | 1 | 1 |
| 1000 | 1 | 2 |
+-------+---------+------+
--> when there are duplicate values, user show up multiple times.
Anyone who can point me in the right direction?
I assume when there are duplicate scores you want the lowest info just like your expected output.
With NOT EXISTS:
select t.* from test t
where not exists (
select 1 from test
where user_id = t.user_id and (
score > t.score or (score = t.score and info < t.info)
)
);
See the demo.
For MySql 8.0+ you can use ROW_NUMBER():
select t.score, t.user_id, t.info
from (
select *, row_number() over (partition by user_id order by score desc, info asc) rn
from test
) t
where t.rn = 1
See the demo.
Results:
| score | user_id | info |
| ----- | ------- | ---- |
| 1000 | 1 | 1 |
| 2001 | 2 | 1 |
If the combination of (user_id, info) is UNIQUE and NOT NULL (or PRIMARY KEY), then you can use a LIMIT 1 subquery in the WHERE clause:
SELECT t.*
FROM test t
WHERE (t.score, t.info) = (
SELECT t2.score, t2.info
FROM test t2
WHERE t2.user_id = t.user_id
ORDER BY t2.score DESC, t2.info ASC
LIMIT 1
)
ORDER BY t.score DESC, t.info ASC;
The result will be:
| score | user_id | info |
|-------|---------|------|
| 2001 | 2 | 1 |
| 1000 | 1 | 1 |
demo on sqlfiddle
SELECT info FROM test HAVING MAX(score) was used to keep the info field relevant with the row containing the MAX(score).
SELECT MAX(score) score, user_id, (SELECT info FROM test HAVING MAX(score)) AS info FROM test GROUP BY user_id ORDER BY score DESC;
DB: MySQL 5.6
users table:
| id | name |
| -- | ---- |
| 1 | A |
| 2 | B |
user_likes table:
| id | user_id | star | created_at |
| -- | ------- | ---- | ------------------- |
| 1 | 1 | 2 | 2018-09-12 00:00:00 |
| 2 | 2 | 3 | 2018-09-12 00:00:00 |
Query 1
select u.name, ul.user_id
from users u, user_likes ul
where u.id = ul.user_id
order by ul.star desc, ul.created_at desc;
Query 2
select u.name, ul.user_id
from users u, user_likes ul
where u.id = ul.user_id
group by ul.user_id
order by ul.star desc, ul.created_at desc;
Why result order changed after add group by ul.user_id in this case?
So want to get unique user_id record from user_likes, how to do?
Because you aren't using any aggregation column and your fields aren't the one on GROUP BY or ORDER BY you are getting random rows.
In your first query you order by ul.star desc, ul.created_at desc if multiple rows have same star and same created_at the result can give your random order for those row.
On your second query you first group by user.id but you don't have any aggregations. there for the field on your select can get any row belong to that group again any random result.
When I said random is more like underterministic, because isnt like a different result each time. Usually depend how the data was stored or if an index was used.
SELECT users.name , user_likes.user_id
FROM user
JOIN user_likes
ON user.id = user_likes.user_id
GROUP BY user.id
order by user_likes.star desc, user_likes.created_at desc;
Best Way Result
Sorry to confuse you about my title. I am building an auction system and I am having a difficulty in getting the user's winning item.
Example I have a table like this:
the columns are:
id, product_id, user_id, status, is_winner, info, bidding_price, bidding_date
here's my sql fiddle:
http://sqlfiddle.com/#!9/7097d/1
I want to get every user's item that they already win. So I need to identify if they are the last who bid in that item.
I need to filter it using a user_id.
If I do a query like this:
SELECT MAX(product_id) AS product_id FROM auction_product_bidding
WHERE user_id = 3;
it will get only the product_id that is 12 and the product_id of 9 did not get. Product ID 9 is also that last bid of the user_id 3.
Can you help me? I hope you got my point. Thanks. Sorry if my question a little bit confusing.
According to your question, seems 11 is also what you want, try this query:
SELECT apd.product_id
FROM auction_product_bidding apd
JOIN (
SELECT MAX(bidding_date) AS bidding_date, product_id
FROM auction_product_bidding
GROUP BY product_id
) t
ON apd.product_id = t.product_id
AND apd.bidding_date = t.bidding_date
WHERE apd.user_id = 3;
Check Demo Here
select id,product_id,user_id,status,is_winner,info,bidding_price,bidding_date,rank
from
( SELECT apb.*,
greatest(#rank:=if(product_id=#prodGrp,#rank+1,1),-1) as rank,
#prodGrp:=product_id as dummy
FROM auction_product_bidding apb
cross join (select #prodGrp:=-1,#rank:=0) xParams
order by product_id,bidding_date DESC
) xDerived
where user_id=3 and rank=1;
That user won 9,11,12
+----+------------+---------+--------+-----------+------+---------------+---------------------+------+
| id | product_id | user_id | status | is_winner | info | bidding_price | bidding_date | rank |
+----+------------+---------+--------+-----------+------+---------------+---------------------+------+
| 60 | 9 | 3 | | 0 | | 75000.00 | 2016-08-02 16:31:23 | 1 |
| 59 | 11 | 3 | | 0 | | 15000.00 | 2016-08-02 12:04:16 | 1 |
| 68 | 12 | 3 | | 0 | | 18000.00 | 2016-08-10 09:20:01 | 1 |
+----+------------+---------+--------+-----------+------+---------------+---------------------+------+
SELECT product_id FROM auction_product_bidding where bidding_price= any
(select max(bidding_price) from auction_product_bidding group by product_id)
and user_id='3';
select * from
(select product_id,user_id,max(bidding_price) from
(select * from auction_product_bidding order by bidding_price desc) a
group by product_id) b
where user_id=3;
Answer:
product_id user_id max(bidding_price)
9 3 75000
11 3 15000
12 3 18000
An idea could be to sort the table desc by date and select every distinct row by product_id and customer_id. Something like
SELECT DISTINCT prod_id, user_id FROM (
SELECT * FROM auction_product_bidding ORDER BY date DESC
)
You want everything that bids last in 3, is it right ?
I have two tables: contacts and client_profiles. A contact has many client_profiles, where client_profiles has foreign key contact_id:
contacts:
mysql> SELECT id,first_name, last_name FROM contacts;
+----+-------------+-----------+
| id | first_name | last_name |
+----+-------------+-----------+
| 10 | THERESA | CAMPBELL |
| 11 | donato | vig |
| 12 | fdgfdgf | gfdgfd |
| 13 | some random | contact |
+----+-------------+-----------+
4 rows in set (0.00 sec)
client_profiles:
mysql> SELECT id, contact_id, created_at FROM client_profiles;
+----+------------+---------------------+
| id | contact_id | created_at |
+----+------------+---------------------+
| 6 | 10 | 2014-10-09 17:17:43 |
| 7 | 10 | 2014-10-10 11:38:01 |
| 8 | 10 | 2014-10-10 12:20:41 |
| 9 | 10 | 2014-10-10 12:24:19 |
| 11 | 12 | 2014-10-10 12:35:32 |
+----+------------+---------------------+
I want to get the latest client_profiles for each contact. That means There should be two results. I want to use subqueries to achieve this. This is the subquery I came up with:
SELECT `client_profiles`.*
FROM `client_profiles`
INNER JOIN `contacts`
ON `contacts`.`id` = `client_profiles`.`contact_id`
WHERE (client_profiles.id =
(SELECT `client_profiles`.`id` FROM `client_profiles` ORDER BY created_at desc LIMIT 1))
However, this is only returning one result. It should return client_profiles with id 9 and 11.
What is wrong with my subquery?
It looks like you were trying to filter twice on the client_profile table, once in the JOIN/ON clause and another time in the WHERE clause.
Moving everything in the where clause looks like this:
SELECT `cp`.*
FROM `contacts`
JOIN (
SELECT
`client_profiles`.`id`,
`client_profiles`.`contact_id`,
`client_profiles`.`created_at`
FROM `client_profiles`
ORDER BY created_at DESC
LIMIT 1
) cp ON `contacts`.`id` = `cp`.`contact_id`
Tell me what you think.
Should be something like maybe:
SELECT *
FROM `client_profiles`
INNER JOIN `contacts`
ON `contacts`.`id` = `client_profiles`.`contact_id`
GROUP BY `client_profiles`.`contact_id`
ORDER BY created_at desc;
http://sqlfiddle.com/#!2/a3f21b/9
You need to prequery the client profiles table grouped by each contact.. From that, re-join to the client to get the person, then again to the client profiles table based on same contact ID, but also matching the max date from the internal prequery using max( created_at )
SELECT
c.id,
c.first_name,
c.last_name,
IDByMaxDate.maxCreate,
cp.id as clientProfileID
from
( select contact_id,
MAX( created_at ) maxCreate
from
client_profiles
group by
contact_id ) IDByMaxDate
JOIN contacts c
ON IDByMaxDate.contact_id = c.id
JOIN client_profiles cp
ON IDByMaxDate.contact_id = cp.contact_id
AND IDByMaxDate.maxCreate = cp.created_at
I have read that grouping happens before ordering, is there any way that I can order first before grouping without having to wrap my whole query around another query just to do this?
Let's say I have this data:
id | user_id | date_recorded
1 | 1 | 2011-11-07
2 | 1 | 2011-11-05
3 | 1 | 2011-11-06
4 | 2 | 2011-11-03
5 | 2 | 2011-11-06
Normally, I'd have to do this query in order to get what I want:
SELECT
*
FROM (
SELECT * FROM table ORDER BY date_recorded DESC
) t1
GROUP BY t1.user_id
But I'm wondering if there's a better solution.
Your question is somewhat unclear but I have a suspicion what you really want is not any GROUP aggregates at all, but rather ordering by date first, then user ID:
SELECT
id,
user_id,
date_recorded
FROM tbl
ORDER BY date_recorded DESC, user_id ASC
Here would be the result. Note reordering by date_recorded from your original example
id | user_id | date_recorded
1 | 1 | 2011-11-07
3 | 1 | 2011-11-06
2 | 1 | 2011-11-05
5 | 2 | 2011-11-06
4 | 2 | 2011-11-03
Update
To retrieve the full latest record per user_id, a JOIN is needed. The subquery (mx) locates the latest date_recorded per user_id, and that result is joined to the full table to retrieve the remaining columns.
SELECT
mx.user_id,
mx.maxdate,
t.id
FROM (
SELECT
user_id,
MAX(date_recorded) AS maxdate
FROM tbl
GROUP BY user_id
) mx JOIN tbl t ON mx.user_id = t.user_id AND mx.date_recorded = t.date_recorded
Iam just using the technique
"Using order clause before group by inserting it in group_concat clause"
SELECT SUBSTRING_INDEX(group_concat(cast(id as char)
ORDER BY date_recorded desc),',',1),
user_id,
SUBSTRING_INDEX(group_concat(cast(`date_recorded` as char)
ORDER BY `date_recorded` desc),',',1)
FROM data
GROUP BY user_id