I have the following data structure:
Table 1(groups):
ID | Group
=============
1 | Sample
2 | Data
Table 2(items):
ID | GroupID | Cost | Amount
==============================
1 | 1 | 1 | 12
2 | 1 | 7 | 15
3 | 1 | 3 | 8
4 | 2 | 2 | 12
And would like the following (query) results:
groups.ID | groups.Name | total
1 | Sample | 141
2 | Data | 24
total is the sum over the products of cost and amount of all items in the group i.e. for group 1: 1*12+7*15+3*8=141
Im guessing I have to something with
SELECT g.ID, g.Group, SUM(Products)
FROM groups AS g, items AS i
WHERE g.ID=i.GroupID
GROUP BY i.GroupID
But don't know what exactly.
Doing iit in clientsoftware with loops is no problem, but I am curious (and certain) that this can be done in (my)Sql
SELECT g.ID as ID, g.Group as Name, SUM(i.Cost * i.Amount) as total
FROM groups g
INNER JOIN items i ON i.GroupID = g.ID
GROUP BY g.Group, g.ID
Having a field named "Group" is quite a bad idea in SQL (reserved keyword)
Related
I'm in front of a "minor" problem taht looks easy but I didn't suceed to resolve it.
I have three tables in my Database :
Table gp
____________
id | name |
____________
1 | Le Mans|
2 | Toulon |
3 | Rennes |
Table player
____________
id | name |
____________
1 | Thibaut|
2 | Fred |
3 | Samir |
Table Records
_____________________________
id | gp_id | player_id | time
_____________________________
1 | 1 | 1 | 17860
2 | 2 | 1 | 11311
3 | 3 | 1 | 33133
4 | 3 | 2 | 11113
5 | 2 | 2 | 44444
6 | 1 | 2 | 13131
7 | 1 | 3 | 11111
8 | 3 | 3 | 21112
I want to get a sum of time for players that have a record on every gp ( so in my case, just players Thibaut and Fred have a record on the 3 gp ( Samir has just a record on two gp ) ).
I have no idea how I can get that, of course this SQL query is retrieving a sum but from this query I want to escape the guys that don't have a record on every GPs, but I'm blocked at that point ...
SELECT p.name, sum(time)
from records r
join gp g on r.gp_id = g.id
join player p on r.player_id = p.id
group by r.player_id
Thanks in advance guys !
You could use having count to exclude the records that don't have a record on every GPs.
Try:
select p.name,
sum(`time`) as tot_sum
from records r
inner join player p on r.player_id=p.id
inner join gp g on g.id=r.gp_id
group by p.name
having count(distinct gp_id) = (select count(distinct id) from gp)
https://dbfiddle.uk/t8QwSFDY
having count(distinct gp_id) = (select count(distinct id) from gp) will match only the records in the record table that have a record on every gp.
I know that the question title may not be quit clear to understand but I try to explain:
users_table:
id | name | admin | property_id
-----------------------------------
1 | x | 1 | 0
2 | y | 1 | 0
3 | z | 0 | 1
5 | t | 0 | 2
6 | u | 0 | 2
7 | o | 0 | 2
users_table has two or more records which are admin and some other records which belong to one of these admin records by matching the property_id with the id. In the end what I want is the admin row data and the count of its properties. This is what should be the output from the first part of the query:
id | name | admin | property_count
-----------------------------------
1 | x | 1 | 1
2 | y | 1 | 3
Until now I know how to get the desired results but here begins the problem.I have another table
sells_table:
id | seller_id | sell_amount
----------------------------
1 | 3 | 250
2 | 5 | 120
3 | 7 | 100
4 | 5 | 200
So this is the logic: every admin has many properties and each property has many sells.
I want all records for each admin from the users_table plus the count of its property_id.
And then query the sells_table in a way where for each property of each admin the number of sells and the sum of the total sells gets calculated.
for example this should be the result for the admin with the id 2 and the name y:
name | properties | property_sells | property_amount
--------------------------------------------------------
y | 3 | 3 | 420
y has 3 properties. Property with id 5 which belongs to y(admin) has two sells and id 7 which also belongs to y(admin) has one sell and the sum of these 3 sells is 420.
I think this is what you want:
select ua.id, ua.name, ua.admin, count(distinct u.id) as property_count,
sum(s.sell_amount) as amount
from users_table ua left join
users_table u
on ua.id = u.property_id left join
sales s
on s.seller_id = u.id
where ua.admin = 1
group by ua.id, ua.name, ua.admin;
http://sqlfiddle.com/#!9/36834d/2
SELECT u.id, U.name, u.admin, COUNT(DISTINCT ut.id) property_count, SUM(st.sell_amount)
FROM users_table u
LEFT JOIN users_table ut
ON u.id = ut.property_id
LEFT JOIN sells_table st
ON ut.id = st.seller_id
WHERE u.admin = 1
GROUP BY u.id, u.admin, u.name
I have this table:
table foo
id | bar_id | user_id
-----------------
1 | 3 | 1
2 | 5 | 1
3 | 6 | 2
4 | 5 | 1
5 | 3 | 2
table bar
id | title | description
------------------------
3 | hey | desc1
5 | ola | desc 2
6 | vassup | desc 3
Then I have this query
const basequery = knex
.select('bar.*')
.from('bar')
.join('foo', 'foo.bar_id', 'bar.id')
.groupBy('foo.bar_id')
.whereIn('foo.user_id', 1);
This will return:
id | title | description
-----------------------
3 | hey | desc 1
5 | ola | desc 2
which is correct.
Basically I'm reusing that basequery multiple times on the file.
Then I want to count the number of rows returned by this.
basequery.clone().countDistinct(`bar.id as total`)
What I'm expecting is:
id | title | description | total
--------------------------------
3 | hey | desc 1 | 2
because there are 2 columns on the foo table with id = 1 and grouped by bar_id. I want to count the number of column returned by the first query as "total".
However, it returns this:
id | title | description | total
--------------------------------
3 | hey | desc 1 | 1
5 | ola | desc 2 | 2
Any help would greatly appreciated
I don't know Knex, but if Knex is anything like Laravel, then you would almost certainly need to use some raw query functionality to get the output you want here. The total you want in the output is just the total number of records in thr query itself. Unfortunately, there is no trick we can use in MySQL to get that count without running the actual query. In the raw query below, I use a non correlated subquery to bring in the total.
SELECT
b.*,
(SELECT COUNT(*) FROM (SELECT b.id FROM bar b INNER JOIN foo f ON f.bar_id = b.id
WHERE f.user_id IN (1) GROUP BY f.bar_id) t) total
FROM bar b
INNER JOIN foo f
ON f.bar_id = b.id
WHERE f.user_id IN (1)
GROUP BY f.bar_id
To be clear, the subquery in the above SELECT list is this:
SELECT COUNT(*)
FROM
(
SELECT b.id
FROM bar b
INNER JOIN foo f
ON f.bar_id = b.id
WHERE f.user_id IN (1)
GROUP BY f.bar_id
) t
I have a SQL table user_game which contains the games that a user owns:
| id | user_id | game_id |
|----|---------|---------|
| 83 | 1 | 1 |
| 84 | 1 | 2 |
| 85 | 1 | 3 |
| 86 | 2 | 2 |
| 87 | 2 | 3 |
| 88 | 2 | 4 |
| 89 | 3 | 2 |
I am trying to count the number of users which have 1 game, 2 games, 3 games.. etc.
User 1 has 3 games, User 2 has 3 games, and User 3 has 1 game. Therefore these are the results I want to achieve:
| no_of_games | COUNT(no_of_games) |
|-------------|--------------------|
| 1 | 1 |
| 2 | 0 |
| 3 | 2 |
COUNT(no_of_games) is the number of users that have that number of games.
I can individually get the number of users for each no_of_games with this query:
-- Select no. of users with 1 game
SELECT no_of_games, COUNT(no_of_games)
FROM
(
-- Select no. of games each user has
SELECT user_id, COUNT(1) as no_of_games
FROM user_game
GROUP BY user_id
) as A
WHERE no_of_games = 1;
which gives the results:
| no_of_games | COUNT(no_of_games) |
|-------------|--------------------|
| 1 | 1 |
However I have to change the no_of_games = 1 to 2, 3, 4... manually and UNION them with this solution and I can't do it for ~60 cases.
Is there a simpler way to achieve this?
Your problem is a bit tricky, because groups of games which do not appear in your data with a certain frequency (e.g. 2) will not appear in the result set just using your original table. In the query below, I use a second table called nums which simply contains the sequence 1 through 10 representing counts of number of games. By using a LEFT JOIN we can retain each game count in the final result set.
SELECT t1.no_of_games,
COALESCE(t2.no_of_games_count, 0) AS no_of_games_count
FROM nums t1
LEFT JOIN
(
SELECT t.no_of_games, COUNT(*) AS no_of_games_count
FROM
(
SELECT COUNT(*) AS no_of_games
FROM user_game
GROUP BY user_id
) t
GROUP BY t.no_of_games
) t2
ON t1.no_of_games = t2.no_of_games
ORDER BY t1.no_of_games
And here is the definition I used for nums:
CREATE TABLE nums (`no_of_games` int);
INSERT INTO nums (`no_of_games`)
VALUES
(1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
Demo here:
SQLFiddle
You can find count of games for each user and then find count of users for each count of games.
select cnt no_of_games, count(*) cnt_no_of_games
from(
select user_id, count(*) cnt
from your_table
group by user_id
) t group by cnt;
I'd like a little help here.
I'm building a database in MySQL where I will have a bunch of different activities. Each activity is part of a list.
So, I have the following tables on my database.
List
id
name
Activity
id
name
idList (FK to List)
I also want to know when each activity is finished (you can finish the same activity many times). To accomplish that, I have another table:
History
date
idActivity (FK to activity)
When the user finishes an activity, I add the id of this activity and the current time the activity was finished, to the History table.
I want to get the entire list with the date it was finished. When an activity has not been finished, I want it to show the date as null.
But, getting the list just once is easy. A simple Left Outer Join will do the trick. My issue here is that I want to get the ENTIRE list everytime a date appears on the history table.
This is what I'm looking for:
List:
id | name
1 | list1
Activity:
id | name | idList
1 | Activity1 | 1
2 | Activity2 | 1
3 | Activity3 | 1
4 | Activity4 | 1
5 | Activity5 | 1
6 | Activity6 | 1
History:
date | idActivity
17/07/14 | 1
17/07/14 | 3
17/07/14 | 4
17/07/14 | 6
16/07/14 | 2
16/07/14 | 3
16/07/14 | 5
Expected Result:
idActivity | idList | activityName | date
1 | 1 | Activity1 | 17/07/14
2 | 1 | Activity2 | NULL
3 | 1 | Activity3 | 17/07/14
4 | 1 | Activity4 | 17/07/14
5 | 1 | Activity5 | NULL
6 | 1 | Activity6 | 17/07/14
1 | 1 | Activity1 | NULL
2 | 1 | Activity2 | 16/07/14
3 | 1 | Activity3 | 16/07/14
4 | 1 | Activity4 | NULL
5 | 1 | Activity5 | 16/07/14
6 | 1 | Activity6 | NULL
The "trick" is to use a CROSS JOIN (or semi-cross join) operation with a distinct list of dates from the history table, to produce the set of rows you want to return.
Then a LEFT JOIN (outer join) to the history table to find the matching history rows.
Something like this:
SELECT a.id AS idActivity
, a.idList AS idList
, a.name AS activityName
, h.date AS `date`
FROM activity a
CROSS
JOIN ( SELECT s.date
FROM history s
GROUP BY s.date
) r
LEFT
JOIN history h
ON h.idActivity = a.id
AND h.date = r.date
ORDER
BY r.date
, a.id
That query gets the six rows from activity, and two rows (distinct values of date) from history (inline view aliased as r). The CROSS JOIN operation matches each of the six rows with each of the two rows, to produce a Cartesian product of 12 rows.
To get the rows returned in the specified order, we order by date, and then by activity.id.