I need to get Max bid and that username but result is coming in wrong way
Here is my two tables
Product
id | name | username
1 | A | deen
2 B | ann
Bid
id | c_bid | username
1 | 10 | ann
1 | 12 | ann
1 | 13 | ann
2 | 10 | ann
1 | 15 | Hel
1 | 16 | Hel
SQL
SELECT name, bid.username AS username, MAX(bid.c_bid) AS c_bid FROM product INNER JOIN bid
ON gems.id= bidding.id WHERE bid.id = '1'
Result
name | c_bid | username
A | 16 | ann
Why is this result coming on this sql?
Since you are using an aggregate function you need to include a GROUP BY.
SELECT name,
bid.username AS username,
MAX(bid.c_bid) AS c_bid
FROM product
INNER JOIN bid
ON product.id= bid.id
WHERE bid.id = '1'
GROUP BY name, bid.username
See SQL Fiddle with Demo
You are getting strange results because MySQL uses an Extension to GROUP BY that allows you to use an aggregate function without using a GROUP BY but this could cause your result to be incorrect.
The GROUP BY makes it so you will return the max(bid) for each item that you are grouping by, in your case it is name and `username.
If you want to return only one max(bid) for each product id, then you could use:
SELECT name,
bid.username AS username,
bid.c_bid
FROM product
INNER JOIN bid
ON product.id= bid.id
INNER JOIN
(
SELECT max(c_bid) c_bid, id
FROM bid
GROUP BY id
) b
on bid.id = b.id
and bid.c_bid = b.c_bid
WHERE bid.id = '1'
See SQL Fiddle with Demo
Use GROUP BY.
SELECT name, bid.username AS username, MAX(bid.c_bid) AS c_bid FROM product INNER JOIN bid
ON gems.id= bidding.id WHERE bid.id = '1' GROUP BY bid.username;
SELECT
p.username,
MAX(b.c_bid) AS max_c_bid
FROM product p
LEFT JOIN bid b ON (p.username = b.username)
GROUP BY p.username;
SELECT
pr.name,
mb.c_bid,
pr.username
FROM
(
SELECT
SUBSTRING_INDEX(GROUP_CONCAT(id ORDER BY c_bid DESC), ',', 1) AS id,
MAX(c_bid) AS c_bid
FROM bid
GROUP BY id
) AS mb
JOIN product AS pr ON(pr.id = mb.id)
Example: http://sqlfiddle.com/#!2/0a6c9/2
Related
I'm currently new to queries and below I have a query that I have made
QUERY:
select TITLE_ID, TITLE,NAME, JOB_CATEGORY AS ROLE
FROM MOVIES
NATURAL JOIN NEW_NAMES
WHERE JOB_CATEGORY = 'writer'
OR JOB_CATEGORY = 'director'
ORDER BY TITLE_ID ASC;
Which Displays:
TITLE_ID | TITLE | NAME | ROLE |
753595 | 2F2F | ROB | WRITER |
753595 | 2F2F | YAS | DIRECTOR|
However I would like it to display in this format below:
TITLE_ID | TITLE | WRITER | DIRECTOR|
753595 | 2F2F | ROB | YAS |
You join your NEW_NAMES table in twice. Once for director, once for writer. When you join a table more than once it's necessary that you give the table an Alias, here we use writer and director.
select TITLE_ID, TITLE,writer.NAME as writer_name, director.NAME as director_name
FROM MOVIES
LEFT OUTER JOIN NEW_NAMES as writer
ON MOVIES.TITLE_ID = writer.TITLE_ID
AND writer.JOB_CATEGORY = 'writer'
LEFT OUTER JOIN NEW_NAMES as director
ON MOVIES.TITLE_ID = director.TITLE_ID
AND director.JOB_CATEGORY = 'director'
ORDER BY TITLE_ID ASC;
I've made some assumptions in those ON clauses about which columns in your tables you are joining on. You may need to edit that.
According to error message you got, it is about Oracle, not MySQL.
Anyway, such a (classic?) principle should work: aggregate!
SQL> with
2 -- sample data
3 movies (title_id, title_name) as
4 (select 753595, '2F2F' from dual union all
5 select 123456, '1Z1Z' from dual
6 ),
7 new_names (title_id, job_category, name) as
8 (select 753595, 'writer', 'ROB' from dual union all
9 select 753595, 'director', 'YAS' from dual
10 )
11 -- query you need
12 select m.title_id,
13 m.title_name,
14 max(case when n.job_category = 'writer' then n.name end) as writer,
15 max(case when n.job_category = 'director' then n.name end) as director
16 from movies m left join new_names n on m.title_id = n.title_id
17 group by m.title_id, m.title_name
18 order by m.title_id;
TITLE_ID TITL WRI DIR
---------- ---- --- ---
123456 1Z1Z
753595 2F2F ROB YAS
SQL>
I'm stuck with sum() query where I want the sum of count(*) values in all rows with group by.
Here is the query:
select
u.user_type as user,
u.count,
sum(u.count)
FROM
(
select
DISTINCT
user_type,
count(*) as count
FROM
users
where
(user_type = "driver" OR user_type = "passenger")
GROUP BY
user_type
) u;
Current Output:
----------------------------------
| user | count | sum |
----------------------------------
| driver | 58 | 90 |
----------------------------------
Expected Output:
----------------------------------
| user | count | sum |
----------------------------------
| driver | 58 | 90 |
| passenger | 32 | 90 |
----------------------------------
If I remove sum(u.count) from query then output is looks like:
--------------------------
| user | count |
--------------------------
| driver | 58 |
| passenger | 32 |
--------------------------
You need a subquery:
SELECT user_type,
Count(*) AS count,
(SELECT COUNT(*)
FROM users
WHERE user_type IN ("driver","passenger" )) as sum
FROM users
WHERE user_type IN ("driver","passenger" )
GROUP BY user_type ;
Note you dont need distinct here.
OR
SELECT user_type,
Count(*) AS count,
c.sum
FROM users
CROSS JOIN (
SELECT COUNT(*) as sum
FROM users
WHERE user_type IN ("driver","passenger" )
) as c
WHERE user_type IN ("driver","passenger" )
GROUP BY user_type ;
You can use WITH ROLLUP modifier:
select coalesce(user_type, 'total') as user, count(*) as count
from users
where user_type in ('driver', 'passenger')
group by user_type with rollup
This will return the same information but in a different format:
user | count
----------|------
driver | 32
passenger | 58
total | 90
db-fiddle
In MySQL 8 you can use COUNT() as window function:
select distinct
user_type,
count(*) over (partition by user_type) as count,
count(*) over () as sum
from users
where user_type in ('driver', 'passenger');
Result:
user_type | count | sum
----------|-------|----
driver | 32 | 90
passenger | 58 | 90
db-fiddle
or use CTE (Common Table Expressions):
with cte as (
select user_type, count(*) as count
from users
where user_type in ('driver', 'passenger')
group by user_type
)
select user_type, count, (select sum(count) from cte) as sum
from cte
db-fiddle
I would be tempted to ask; Are you sure you need this at the DB level?
Unless you are working purely in the database layer, any processing of these results will be built into an application layer and will presumably require some form of looping through the results
It could be easier, simpler, and more readable to run
SELECT user_type,
COUNT(*) AS count
FROM users
WHERE user_type IN ("driver", "passenger")
GROUP BY user_type
.. and simply add up the total count in the application layer
As pointed out by Juan in another answer, the DISTINCT is redundant as the GROUP BY ensures that each resultant row is different
Like Juan, I also prefer an IN here, rather than OR condition, for the user_type as I find it more readable. It also reduces the likelihood of confusion if combining further AND conditions in the future
As an aside, I would consider moving the names of the user types, "driver" and "passenger" into a separate user_types table and referencing them by an ID column from your users table
N.B. If you absolutely do need this at the DB level, I would advocate using one of Paul's excellent options, or the CROSS JOIN approach proffered by Tom Mac, and by Juan as his second suggested solution
Try this. Inline view gets the overall total :
SELECT a.user_type,
count(*) AS count,
b.sum
FROM users a
JOIN (SELECT COUNT(*) as sum
FROM users
WHERE user_type IN ("driver","passenger" )
) b ON TRUE
WHERE a.user_type IN ("driver","passenger" )
GROUP BY a.user_type;
You could simply combine SUM() OVER() with COUNT(*):
SELECT user_type, COUNT(*) AS cnt, SUM(COUNT(*)) OVER() AS total
FROM users WHERE user_type IN ('driver', 'passenger') GROUP BY user_type;
db<>fiddle demo
Output:
+------------+------+-------+
| user_type | cnt | total |
+------------+------+-------+
| passenger | 58 | 90 |
| driver | 32 | 90 |
+------------+------+-------+
Add a group by clause at the end for user-type, e.g:
select
u.user_type as user,
u.count,
sum(u.count)
FROM
(
select
DISTINCT
user_type,
count(*) as count
FROM
users
where
(user_type = "driver" OR user_type = "passenger")
GROUP BY
user_type
) u GROUP BY u.user_type;
Tom Mac Explain Properly Your answer. Here is the another way you can do that.
I check the query performance and not found any difference within 1000 records
select user_type,Countuser,(SELECT COUNT(*)
FROM users
WHERE user_type IN ('driver','passenger ') )as sum from (
select user_type,count(*) as Countuser from users a
where a.user_type='driver'
group by a.user_type
union
select user_type,count(*) as Countuser from users b
where b.user_type='passenger'
group by b.user_type
)c
group by user_type,Countuser
Try this:
WITH SUB_Q AS (
SELECT USER_TYPE, COUNT (*) AS CNT
FROM USERS
WHERE USER_TYPE = "passenger" OR USER_TYPE = "driver"
GROUP BY USER_TYPE
),
SUB_Q2 AS (
SELECT SUM(CNT) AS SUM_OF_COUNT
FROM SUB_Q
)
SELECT A.USER_TYPE, A.CNT AS COUNT, SUB_Q2 AS SUM
FROM SUB_Q JOIN SUB_Q2 ON (TRUE);
I used postgresql dialect but you can easily change to a subquery.
select
u.user_type as user,
u.count,
sum(u.count)
FROM users group by user
I am working on an problem regarding Selecting data from two MySQL tables.
First table holds messages | messages | (id, msg_group_id, to_user_id, from_user_id, datetime)
Second table holds user data | profiles | (user_id, name, firstname, ...)
ATM it works the way, that I can select ALL messages with a certain 'to_id' and by adding a JOIN statement getting the name and firstname of the user who sends the message.
My problem now is that I can not figure out a way to ONLY select the newest message of a certain msg_group_id.
I already tried GROUP BY msg_group_id combined with ORDER BY datetime DESC.
But that only throws the very first entry in message table. But I want to last one. :-)
I hope you can help me. :-)
My actual SQL statement:
SELECT LEFT(messages.message, 10) AS message,
`messages`.`msg_group_id`,
`messages`.`datetime`,
`profiles`.`name`,
`profiles`.`firstname`
FROM `messages`
LEFT JOIN `profiles`
ON `messages`.`from_user_id` = `profiles`.`user_id`
WHERE `to_user_id` = '2'
ORDER BY `datetime` DESC
LIMIT 20;
Thanks in Advance
Sample INPUT:
[messages]
|id|msg_group_id|to_user_is|from_user_id|message |datetime|
0 | 1 | 1 | 2 | Hello World1 | 2015-12-21 10:42:00
1 | 1 | 1 | 2 | Hello World2 | 2015-12-21 10:43:00
2 | 1 | 1 | 2 | Hello World3 | 2015-12-21 10:44:00
[profiles]
user_id|name |firstname|
1 | Test | User
2 | Thanks | Worldname
Result (what I don't want)
message|msg_group_id|datetime|name|firstname
Hello World1 | 1 | 2015-12-21 10:42:00 | Thanks | Worldname
Result (what I want)
message|msg_group_id|datetime|name|firstname
Hello World3 | 1 | 2015-12-21 10:44:00 | Thanks | Worldname
May be this query can help:
SELECT m.message, m.msg_group_id, m.datetime, u.name, u.firstname
FROM message as m, profiles as u
WHERE m.from_user_id = u.user_id
GROUP BY m.msg_group_id
ORDER BY m.datetime DESC
Or use INNER JOIN
SELECT m.message, m.msg_group_id, m.datetime, u.name, u.firstname
FROM message as m
INNER JOIN profiles as u ON m.from_user_id = u.user_id
GROUP BY m.msg_group_id
ORDER BY m.datetime DESC
I guess I solved the Problem with the help of another thread:
https://stackoverflow.com/a/1313140/4493030
My SQL Statement as follows:
SELECT `messages`.*, `profiles`.`nick_name`
FROM `messages`
LEFT JOIN `profiles`
ON `messages`.`from_user_id` = `profiles`.`user_id`
INNER JOIN
(SELECT konversation_id, MAX(id) AS maxid FROM messages
WHERE messages.to_user_id = 2
GROUP BY konversation_id) AS b
ON messages.id = b.maxid
WHERE `to_user_id` = '2'
ORDER BY `datetime` DESC
LIMIT 20;
Thanks to all of you who tried to help.
I found a way to tight it down
SELECT messages.to_user_id, messages.msg_group_id, MAX(messages.id) AS maxid, messages.from_user_id, profiles.name
FROM messages
LEFT JOIN profiles
ON messages.from_user_id = profiles.user_id
WHERE messages.to_user_id = 2
GROUP BY msg_group_id
So basically, I require a query that will return display name, amount of kills and amount of deaths.
I have two tables that I need to pull from.
The two tables are
player
id | name
2334324 | user
4353454 | user2
where id is their unique identifier and name is their display name.
The second table is:
player_kill
id | killer | victim |
1 | 2334324 | 4353454 |
2 | 2334324 | 4353454 |
3 | 4353454 | 2334324 |
where killer / victim columns contain the unique identifier of the player table.
I'd like to be able to count the occurrences of player id in the killer and victim so that the query returns:
name | kills | deaths
user | 2 | 1
user2| 1 | 2
where the number under kills would be the amount of occurrences the playerid has in the killer column and same for deaths
Hope I provided enough information.
What I have so far:
SELECT `player`.`name`, COUNT(DISTINCT `player_kill`.`id`) as `kills`, COUNT(DISTINCT `player_kill`.`id`) as `deaths`
FROM `player`
LEFT JOIN `player_kill` ON `player`.`id`=`player_kill`.`killer`
LEFT JOIN `player_kill` ON `player`.`id`=`player_kill`.`victim`
WHERE `player`.`id` = `player_kill`.`killer` AND `player`.`id` = `player_kill`.`victim`
GROUP BY `player`.`id`;
Try
SELECT
p.name,
count(distinct pk1.id) as kills,
count(distinct pk2.id) as deaths
FROM player p
LEFT JOIN player_kill pk1 ON pk1.killer = p.id
LEFT JOIN player_kill pk2 ON pk2.victim = p.id
group by p.name
http://sqlfiddle.com/#!9/649504/15/0
See if this works:
SELECT `player`.`name`,
COUNT(DISTINCT k.`id`) as `kills`,
COUNT(DISTINCT v.`id`) as `deaths`
FROM `player`
LEFT JOIN `player_kill` AS k ON `player`.`id` = k.`killer`
LEFT JOIN `player_kill` AS v ON `player`.`id` = v.`victim`
GROUP BY `player`.`id`;
If not, then we may need to make the COUNTs into subqueries.
I have 2 tables.
Table Matches
id | TeamA | TeamB
--------------
1 | Barça | Madrid
2 | Valencia | Depotivo
Table Payments
idMatch | User | Quantity
---------------------------
1 | Me | 50
2 | Me | 100
Then in one query I want to get TeamA, TeamB, User and Quantity if they have same id.
I've tried this but it fails.
SELECT TeamA, TeamB FROM Matches WHERE id IN (SELECT idMatch, TeamA, TeamB FROM Payments)
try this
SELECT TeamA, TeamB ,User , Quantity FROM Matches m
inner join Payments p
on p.idMatch = m.id
WHERE id IN
(SELECT idMatch FROM Payments)
DEMO HERE
you can use joins
select Matches.TeamA,Matches.TeamB,Payments.User,Payments.Quantity from Matches,Payments where Matches.id=Payments.idMatch
try this
SELECT payments.user,
payments.quantity
FROM
Payments
INNER JOIN Matches ON (Matches.id = Payments.idMatch);
IN() should contain a list of values like IN('red','green','blue') or IN(1,3,53). SELECT is fine, but it has to return a single field. This would work.
SELECT TeamA, TeamB FROM Matches
WHERE id IN (
SELECT idMatch FROM Payments
)
However it looks like you want to achieve something you need JOIN or GROUP BY for.
Try
SELECT
TeamA,
TeamB,
payments.user,
payments.quantity
FROM
matches
JOIN payments ON ( matches.id = payments.matchid )
select m.TeamA,m.TeamB,p.`User`,p.Quantity from matches m INNER join
payments p where p.idMatch=m.id