I have 3 models (tables):
Presentation hasMany PresentationView hasMany SlideView
Fields:
Presentation: id, title
PresentationView: id, presentation_id
SlideView: id, presentation_view_id, duration
I need a query to get statistics for each presentation. Statistics are:
number of PresentationView per each Presentation
total duration of all SlideView.duration from slide views that belong to Presentation (through PresentationView)
So basically it seems like double JOIN and double GROUP but the joins doesn't work for me - I tried every combination of LEFT/INNER/RIGHT double joins and I can't make it work. The best I had it was that Presentation had grouped PresentationView but duration was SUMed just from SlideViews that belonged to just one PresentationViews not all for Presentation...
I would like to avoid nested SELECTs if possible. just JOIN/GROUP
The first thing is a simple JOIN and COUNT:
SELECT p.id, COUNT(*)
FROM Presentation p
JOIN PresentationView v ON p.id = v.presentation_id
GROUP BY p.id
The second one has to use a SUM (and JOIN):
SELECT p.id, SUM(s.duration)
FROM Presentation p
JOIN PresentationView v ON p.id = v.presentation_id
JOIN SlideView s ON v.id = s.presentation_view_id
GROUP BY p.id
If you want both in a single query:
SELECT p.id, SUM(s.duration), COUNT(DISTINCT v.id)
FROM Presentation p
JOIN PresentationView v ON p.id = v.presentation_id
JOIN SlideView s ON v.id = s.presentation_view_id
GROUP BY p.id
Reason for DISTINCT:
Tables:
Presentation: PresentationView: SlideView:
p.id | title v.id | presentation_id s.id | presentation_view_id | duration
1 | abc 1 | 1 1 | 1 | 100
2 | xyz 2 | 1 2 | 1 | 150
3 | 1 3 | 2 | 200
4 | 1 4 | 2 | 250
5 | 1 5 | 3 | 300
6 | 2 6 | 3 | 400
7 | 2 7 | 4 | 500
8 | 5 | 600
9 | 6 | 100
10 | 6 | 200
11 | 7 | 350
Example result set BEFORE the group:
p.id | v.id | s.id | s.duration
-------------------------------
1 | 1 | 1 | 100
1 | 1 | 2 | 150
1 | 2 | 3 | 200
1 | 2 | 4 | 250
1 | 3 | 5 | 300
1 | 3 | 6 | 400
1 | 4 | 7 | 500
1 | 5 | 8 | 600
2 | 6 | 9 | 100
2 | 6 | 10 | 200
2 | 7 | 11 | 350
AFTER the group without distinct:
p.id | SUM | COUNT
------------------
1 | 8 | 2500
2 | 3 | 650
With distinct:
p.id | SUM | COUNT
------------------
1 | 5 | 2500
2 | 2 | 650
In mean time I found answer:
SELECT presentations.title, SUM(slide_views.duration), COUNT(DISTINCT presentation_views.id)
FROM presentations
LEFT JOIN presentation_views ON presentations.id = presentation_views.presentation_id
LEFT JOIN slide_views ON presentation_views.id = slide_views.presentation_view_id
GROUP BY presentations.id
Related
I have 2 tables.
SELECT * FROM purchases;
+------+---------+-----------+
|purid | total_q | dstatus |
+------+---------+-----------+
| 1 | 45 | DELIVERED |
| 2 | 50 | LOADING |
| 3 | 24 | DELIVERED |
| 4 | 15 | DELIVERED |
| 5 | 10 | DELIVERED |
+------+---------------------+
SELECT * FROM warehouse;
+------+-------+---------+
| wid | purid | total_q |
+------+-------+---------+
| 4 | 1 | 45 |
| 5 | 4 | 15 |
| 9 | 3 | 10 |
| 12 | 3 | 5 |
+------+-------+---------+
I want to get "delivered" purchases with its amounts which are not already included in warehouse table. Here is the demo where I stuck: DEMO
The query which I use is:
SELECT p.purid as purid, (p.total_q - IFNULL(w.total_q,0)) as ntq
FROM `purchases` as p
LEFT JOIN `warehouse` as w ON p.purid=w.purid
WHERE p.dstatus = "DELIVERED" AND (p.total_q - IFNULL(w.total_q,0)) > 0
My desired output:
+-------+------+
| purid | ntq |
+-------+------+
| 5 | 10 |
| 3 | 9 |
+------+-------+
The problem is I could not subtract "total_q (24) from purchases table" from "sum total_q(10+5) from warehouse table".
You can try to use subquery aggregate warehouse by purid before join otherwise you might get multiple rows.
Query #1
SELECT p.purid as purid,
p.total_q - IFNULL(w.total_q,0) as ntq
FROM `purchases` as p
LEFT JOIN (
SELECT purid,SUM(total_q) total_q
FROM warehouse
GROUP BY purid
) as w ON p.purid=w.purid
WHERE p.dstatus = "DELIVERED"
AND p.total_q - IFNULL(w.total_q,0) > 0;
purid
ntq
3
9
5
10
View on DB Fiddle
I have the following tables
table anag (customer registry)
id | surname | name | phone |
----------------------------------------------
1 | Brown | Jack | +3989265781 |
2 | Smith | Bill | +3954872358 |
3 | Rogers | Stan | +3912568453 |
4 | Pickford | Eric | +3948521358 |
----------------------------------------------
table levels (table that connects each customer to his salesperson. For database registration reasons, the link between customer and seller is given by the customer's telephone number)
id | client_phone | id_seller |
--------------------------------------
1 | +3989265781 | 4 |
2 | +3954872358 | 7 |
3 | +3912568453 | 7 |
4 | +3948521358 | 8 |
--------------------------------------
table orders (contains all purchases made by customers, of course)
id | id_client | id_item | id_seller | price | status |
--------------------------------------------------------------------
1 | 1 | 2 | 4 | 12.50 | 2 |
2 | 2 | 2 | 7 | 12.50 | 2 |
3 | 2 | 3 | 7 | 10.00 | 3 |
4 | 2 | 3 | 7 | 10.00 | 3 |
5 | 2 | 4 | 7 | 20.50 | 1 |
6 | 3 | 2 | 7 | 12.50 | 1 |
7 | 3 | 5 | 7 | 19.00 | 3 |
8 | 3 | 7 | 7 | 31.00 | 2 |
9 | 4 | 1 | 8 | 5.00 | 1 |
--------------------------------------------------------------------
What I'm trying to do is get from the JOIN of these tables a complete list by seller of his customers sorted in descending order by the amount spent on orders as long as the order status is 2 or 3
Something like this (example seller id 7):
id | surname | name | amaount |
----------------------------------------
3 | Rogers | Stan | 50.00 |
2 | Smith | Bill | 32.50 |
----------------------------------------
I have tried with this query which seems correct to me, but unfortunately it returns me error in fetch_assoc()
SELECT a.id, a.surname, a.name, o.amount FROM levels AS l
JOIN anag AS a ON a.phone = l.client_phone
JOIN {
SELECT id_client, SUM(price) AS amount FROM orders
WHERE id_seller = '7' AND (status = '2' OR status = '3') GROUP BY id_client
} AS o ON o.id_client = a.id
WHERE l.id_seller = '7'
ORDER BY o.amount DESC
If I separate the subquery from the main query, both return the data I expect and it seems strange to me the JOIN between the two does not work properly
I think the only real error is using curly braces instead of parentheses:
SELECT a.id, a.surname, a.name, o.amount
FROM levels l JOIN
anag a
ON a.phone = l.client_phone JOIN
(SELECT id_client, SUM(price) AS amount
FROM orders
WHERE id_seller = '7' AND status IN ('2', '3'))
GROUP BY id_client
) o
ON o.id_client = a.id
WHERE l.id_seller = '7'
ORDER BY o.amount DESC;
In addition:
You can use IN to shorten an equality comparison to multiple values.
Although I left them in, status and id_seller look like numbers. If so, drop the single quotes. Don't mix data types.
Your question is ambiguous on what to do if the seller in orders differs from the seller in anag for a customer. This keeps your logic (the sellers need to match).
SELECT a.id, a.surname, a.name, sum(o.price) 'amount'
FROM anag a
LEFT JOIN levels l ON l.id =a.id
LEFT JOIN orders of ON o.id_seller = l.id_seller AND o.id_client = l.id
GROUP BY o.id_seller
ORDER BY amount DESC
I have 3 MySQL tables. I've trimmed them down to show just the important columns
items
id | title |
1 | Hamlet |
2 | Romeo and Juliet |
3 | The Merchant of Venice |
listings
id | item_id | condition |
1 | 1 | Mint |
2 | 1 | Used - Good |
3 | 2 | New |
4 | 2 | Mint |
5 | 2 | Used - Poor |
6 | 3 | Used - Poor |
7 | 3 | Used - Good |
8 | 3 | Used - Good |
itemListings_variations
id | listing_id | price
1 | 1 | 20.00
2 | 1 | 10.00
3 | 1 | 5.00
4 | 2 | 6.00
5 | 2 | 5.50
6 | 3 | 2.00
7 | 4 | 12.00
8 | 5 | 3.00
9 | 6 | 9.00
If e.g. I search for Romeo and Juliet, it should return:
item_id | title | min_price
2 | Romeo and Juliet | 2.00
So far I have two queries which somehow need combining via subqueries and joins. I have:
SELECT
i.id AS item_id,
i.title
FROM items i
WHERE MATCH (i.title) AGAINST (:search)
also:
SELECT
l.item_id,
v.listing_id,
MIN(price) AS min_price
FROM itemListings_variation v, itemListings l
WHERE v.listing_id = l.id
GROUP BY v.listing_id
Try this -
SELECT i.id, i.title, MIN(price)
FROM items i
INNER JOIN listings l ON i.items = l.item_id
INNER JOIN itemListings_variations il ON l.id = il.listing_id
GROUP BY i.id, i.title
Hope this helps.
No group by is needed as calling min(price) will return the row with the lowest price.
select t1.id, title, min(price) from
(select * from items where title = 'Romeo and Juliet' ) as t1
left join listings on t1.id = listings.item_id
left join itemlistings_variations on listing_id = listings.id;
Tested on my test server.
I have MySQL tables that look like this
users
user_id | partner_id | name
--------+------------+-----
1 | 2 | aaa
2 | 1 | bbb
3 | 4 | ccc
4 | 3 | ddd
games
game_id | user_id
--------+--------
1 | 1
2 | 1
3 | 2
4 | 3
5 | 4
6 | 4
scores
game_id | level | score | time
--------+-------+-------+-----
1 | 1 | 1 | 10
1 | 2 | 1 | 10
1 | 3 | 1 | 10
2 | 1 | 0 | 20
2 | 2 | 0 | 20
2 | 3 | 0 | 20
3 | 1 | 1 | 30
3 | 2 | 1 | 30
3 | 3 | 1 | 30
4 | 1 | 1 | 2
4 | 2 | 1 | 2
4 | 3 | 1 | 2
5 | 1 | 1 | 5
5 | 2 | 1 | 5
5 | 3 | 1 | 5
6 | 1 | 1 | 3
6 | 2 | 1 | 3
6 | 3 | 0 | 3
And i need to query it so it sums points and time per game, so it looks like this
game_id | user_id | sumPoints | sumTime
--------+---------+-----------+--------
1 | 1 | 3 | 30
2 | 1 | 0 | 60
3 | 2 | 3 | 90
4 | 3 | 3 | 6
5 | 4 | 3 | 15
6 | 4 | 2 | 9
And then i need to get best scores per pair (where it takes better score of one user), so it looks like this:
user1_id | user2_id | sumPoints | sumTime
---------+----------+-----------+--------
3 | 4 | 3 | 6
1 | 2 | 3 | 30
That's the final result. I'd really appreciate if someone could show me how it should looks like as sql query.
I'd like to mention that first part is solved by JW 웃 in this post
Thanks in advance.
Something like this should work (this answers your second query)
SELECT
user_details.user_id,
user_details.partner_id,
score_details.score,
score_details.time
FROM
( SELECT
min(user_id) as user_id,
max(user_id) as partner_id
FROM
users
GROUP BY
user_id + partner_id ) AS user_details
JOIN
( SELECT
scores.game_id ,
games.user_id,
sum(score) score,
sum(time) time,
#row_num := IF(#prev_value=games.user_id,#row_num+1,1) AS row_num,
#prev_value := games.user_id
FROM
scores
inner join games on games.game_id = scores.game_id
inner join users on users.user_id = games.user_id
GROUP BY
scores.game_id
ORDER BY
user_id,
score
) as score_details ON ( score_details.user_id = user_details.user_id AND score_details.row_num = 1)
The first part of JOIN gets the users along with their partners, users appearing first within their pair are displayed first, eg: if there are 2 users with ID 1 and 2 I consider the user_id of user 1 as he appears first within his pair.
The second query is based on "echo_me" answer along with a row_number that specifies the ranking of the scores for each user, the highest score has the rank as 1 for every user.
SQLFIDDLE
Hope this is helpful
try this
select scores.game_id ,games.user_id,sum(score) score, sum(time) time
from scores
inner join games
on games.game_id = scores.game_id
inner join users
on users.user_id = games.user_id
group by scores.game_id
DEMO HERE
for the best score
select users.user_id as user1_id,users.partner_id as user2_id,sum(score) score, sum(time) time
from scores
inner join games
on games.game_id = scores.game_id
inner join users
on users.user_id = games.user_id
group by scores.game_id
order by sum(time) asc limit 1
DEMO HERE
OUTPUT.
USER1_ID USER2_ID SCORE TIME
1 2 3 30
In a last Question, i asked about geting all actions of the last three users from a history table that stores all actions done by users on deferments posts, now what i want is to get the same thing but for each post.
all actions of the last three users for each posts
history table
id | post_id | action | user_id
1 | 5 | 1 | 3
1 | 23 | 2 | 1
2 | 24 | 2 | 6
3 | 34 | 1 | 7
4 | 35 | 1 | 1
5 | 36 | 1 | 1
6 | 23 | 2 | 3
7 | 24 | 2 | 1
8 | 23 | 1 | 4
9 | 24 | 1 | 5
10 | 24 | 1 | 1
11 | 23 | 1 | 2
12 | 23 | 4 | 1
thanks and sorry if it seem to be a duplicate post
This is a query that requires lots of self joins:
select hl.post_id, h.*
from history h join
(select h.*, count(*) as NumLater
from history h join
history h2
on h.post_id = h2.post_id and
h2.id >= h.id
group by h.id
having NumLater <= 3
) hl
on h.user_id = hl.user_id
order by hl.post_id
The inner query does a self join to calculate the number of history entries after each record in the same post. The join then joins this by user_id to the history table. This version does not eliminate duplicates. So, a user could be in the last-three set for two different posts.