for a little project(hobby purpose) i am building a C# application with a SQL database behind it.
However I am trying to build a query with a sum function which calculates values from a different table.
Here are the relevant tables and sample data
Hotel table
Id, Name Adress Zipcode Phone
1 Ankunding Group 90 Shelley Terrace 649-6326 86-(672)239-5855
2 Gerlach-Gutmann 50776 Bartillon Road 27109 CEDEX 33-(412)226-8055
3 Breitenberg-Smith 3289 Talisman Avenue 59762 86-(141)636-8780
4 Smitham-Marks 5 Veith Plaza 216282 7-(400)484-7233
5 Beatty LLC 3 Center Pass 940028 212-(310)974-4364
Reservation table
id, customerid, Startdate Enddate Amount of persons
1 163 2016-06-19 2017-04-30 4
2 172 2016-12-02 2016-08-18 5
3 162 2017-01-20 2017-04-08 3
4 66 2017-04-06 2017-01-07 2
5 104 2017-05-07 2016-09-10 2
RoomReservation table
Roomid, reservationid
3 53
3 198
4 178
5 172
5 218
Room table
id, hotelid, Roomnumber, price
1 1 1.01 268.83
2 1 1.02 201.28
3 1 1.03 126.64
4 1 1.04 122.56
5 1 1.05 217.41
Now I am trying to make a query to which gives me an overview off income per hotel. So for each hotel I want to get the reservations, and do amount of persons * the price of the room for each room in the hotel.
I've tried different things without success, I read somewhere that I needed to use a subquery but I have no idea how.
I want it to look like;
Hotelname1; income
Hotelname2; income
Hotelname3; income
Hotelname4; income
Hotelname4; income
Why can't you just do this:
SELECT
Hotel.Name,
SUM(Room.Price*Reservation.Amountofpersons)
FROM
Hotel
JOIN Room
ON Hotel.HotelId=Room.HotelId
JOIN RoomReservation
ON Room.RoomId=RoomReservation.RoomId
JOIN Reservation
ON RoomReservation.ReservationId=Reservation.ReservationId
GROUP BY
Hotel.Name
You can try it whit this query:
select hotel.name,sum(reservation.amount*room.price)
from hotel_table as hotel
inner join room_table as room on (hotel.hotelid=room.hotelid)
inner join roomreservation_table as room_reservation on (room.roomid=room_reservation.roomId)
inner join reservation_table as reservation on (room.reservationId=reservation.reservationid)
group by hotel.hotelid
Related
I have a table named orders in a Postgres database that looks like this:
customer_id order_id order_date price product
1 2 2021-03-05 15 books
1 13 2022-03-07 3 music
1 14 2022-06-15 900 travel
1 11 2021-11-17 25 books
1 16 2022-08-03 32 books
2 4 2021-04-12 4 music
2 7 2021-06-29 9 music
2 20 2022-11-03 8 music
2 22 2022-11-07 575 travel
2 24 2022-11-20 95 food
3 3 2021-03-17 25 books
3 5 2021-06-01 650 travel
3 17 2022-08-17 1200 travel
3 19 2022-10-02 6 music
3 23 2022-11-08 70 food
4 9 2021-08-20 3200 travel
4 10 2021-10-29 2750 travel
4 15 2022-07-15 1820 travel
4 21 2022-11-05 8000 travel
4 25 2022-11-29 27 books
5 1 2021-01-04 3 music
5 6 2021-06-09 820 travel
5 8 2021-07-30 19 books
5 12 2021-12-10 22 music
5 18 2022-09-19 20 books
Here's a SQL Fiddle: http://sqlfiddle.com/#!17/262fc/1
I'd like to return the average money spent by customers per product, but only consider orders within the first 12 months of a given customer's first purchase within the given product group. (yes, this is challenging!)
For example, for customer 1, order ID 2 and order ID 11 would be factored into the average for books(because order ID 11 took place less than 12 months after customer 1's first order for books, which was order ID 2), but order ID 16 would not be factored into the average (because 8/3/22 is more than 12 months from customer 1's first purchase for books, which took place on 3/5/21).
Here is a matrix showing which orders would be included within a given product (denoted by "yes"):
The desired output would look as follows:
average_spent
books 22.20
music 7.83
travel 1530.71
food 82.50
How would I do this?
Thanks in advance for any assistance you can give!
You can use a subquery to check whether or not to include a product's price in the summation:
select o.product, sum(o.price)/count(*) val from orders o
where o.order_date < (select min(o1.order_date) from orders o1 where
o1.product = o.product and o.user_id = o1.user_id) + interval '12 months'
group by o.product
See fiddle
I am trying to get the count of patients by province for my school project, I have managed to get the count and the Id of the province in a table but since I am using the count statement it will not let me use join to show the ProvinceName instead of the Id (it says it's not numerical).
Here is the schema of the two tables I am talking about
The content of the Province table is as follow:
ProvinceId
ProvinceName
ProvinceShortName
1
Terre-Neuve-et-Labrador
NL
2
Île-du-Prince-Édouard
PE
3
Nouvelle-Écosse
NS
4
Nouveau-Brunswick
NB
5
Québec
QC
6
Ontario
ON
7
Manitoba
MB
8
Saskatchewan
SK
9
Alberta
AB
10
Colombie-Britannique
BC
11
Yukon
YT
12
Territoires du Nord-Ouest
NT
13
Nunavut
NU
And here is n sample data from the Patient table (don't worry it's fake data!):
SS
FirstName
LastName
InsuranceNumber
InsuranceProvince
DateOfBirth
Sex
PhoneNumber
2
Doris
Patel
PATD778276
5
1977-08-02
F
514-754-6488
3
Judith
Doe
DOEJ7712917
5
1977-12-09
F
418-267-2263
4
Rosemary
Barrett
BARR05122566
6
2005-12-25
F
905-638-5062
5
Cody
Kennedy
KENC047167
10
2004-07-01
M
604-833-7712
I managed to get the patient count by province using the following statement:
select count(SS),InsuranceProvince
from Patient
full JOIN Province ON Patient.InsuranceProvince = Province.ProvinceId
group by InsuranceProvince
which gives me the following table:
PatientCount
InsuranceProvince
13
1
33
2
54
3
4
4
608
5
1778
6
25
7
209
8
547
9
649
10
6
11
35
12
24
13
How can I replace the id's with the correct ProvinceShortName to get the following final result?
ProvinceName
PatientCount
NL
13
PE
33
NS
54
NB
4
QC
608
ON
1778
MB
25
SK
209
AB
547
BC
649
YT
6
NT
35
NU
24
Thanks in advance!
So you can actually just specify that in the select. Note that it's best practise to include the thing you group by in the select, but since your question is so specific then...
SELECT ProvinceShortName, COUNT(SS) AS PatientsInProvince
FROM Patient
JOIN Province ON Patient.InsuranceProvince=Province.ProvinceId
GROUP BY InsuranceProvince;
I would suggest:
select pr.ProvinceShortName, count(*)
from Patient p join
Province pr
on p.InsuranceProvince = pr.ProvinceId
group by pr.ProvinceShortName
order by min(pr.ProvinceId);
Notes:
The key is including the columns you want in the select and group by.
You seem to want the results in province number order, so I included an order by.
There is no need to count the non-NULL values of SS. You might as well use count(*).
Table aliases make the query easier to write and to read.
I assume that you need to show the patient count by province.
SELECT
Province.ProvinceShortName AS [ProvinceName]
,COUNT(1) as [PatinetCount]
FROM Patient
RIGHT JOIN Province ON Patient.InsuranceProvince = Province.ProvinceId
GROUP BY ProvinceShortName
Just altering your query to
select ProvinceShortName As PatientCount,count(InsuranceProvince) As PatientCount
from Patient
full JOIN Province ON Patient.InsuranceProvince = Province.ProvinceId
group by ProvinceShortName
For school I need to make a function on an auction website. For this I need to join a couple of tables in a VIEW. This worked just fine, until I needed to add a filter for price range. Seems easy enough but the query result needs to allow a NULL when no bid has been placed.
The Statement for the View:
SELECT I.itemID, I.title, I.startPrice, B.highestBid, Cfi.category, I.endDate
FROM dbo.Items AS I INNER JOIN dbo.category_for_item AS Cfi ON V.itemID = Vir.itemID
LEFT OUTER JOIN dbo.Bid AS B ON V.itemID = B.itemID
This would get the following Table:
itemID title startPrice highestBid category endDate
1 1234 Alfa 25 26 PC 2018-09-22
2 1234 Alfa 25 NULL PC 2018-09-22
3 5678 Bravo 9 20 Console 2018-07-03
4 5678 Bravo 9 15 Console 2018-07-03
5 5678 Bravo 9 NULL Console 2018-07-03
6 9876 Charlie 84 100 Stamps 2018-06-14
7 9876 Charlie 84 90 Stamps 2018-06-14
8 9876 Charlie 84 85 Stamps 2018-06-14
9 9876 Charlie 84 NULL Stamps 2018-06-14
10 1470 Delta 98 100 Fashion 2018-06-15
11 1470 Delta 98 99 Fashion 2018-06-15
12 1470 Delta 98 NULL Fashion 2018-06-15
13 9631 Echo 56 65 Cars 2018-06-25
14 9631 Echo 56 NULL Cars 2018-06-25
15 7856 Foxtrot 98 NULL Dolls 2018-12-26
After looking around for answers I got a query for joining the VIEW on itself with only showing the highest bid instead of all bids:
SELECT VW.itemID, VW.title, VW.startPrice, VW.highestBid, VW.category, VW.endDate
FROM VW_SEARCH AS VW
INNER JOIN (SELECT itemID, MAX(highestBid) AS MaxBid
FROM VW_SEARCH
GROUP BY itemID) VJ
ON VW.itemID = VJ.itemID AND VW.highestBid = VJ.MaxBid
This gave the next results:
itemID title startPrice highestBid category endDate
1 1234 Alfa 25 26 PC 2018-09-22
2 5678 Bravo 9 20 Console 2018-07-03
3 9876 Charlie 84 85 Stamps 2018-06-14
4 1470 Delta 98 100 Fashion 2018-06-15
5 9631 Echo 56 65 Cars 2018-06-25
As I expected the result only showed the items with at least one bid on them. I tried added one extra condition on the subQuery and Joining RIGHT OUTER to make sure I would not get doubles of an itemID.
SELECT VW.itemID, VW.title, VW.startPrice, VW.highestBid, VW.category, VW.endDate
FROM VW_SEARCH AS VW
RIGHT OUTER JOIN (SELECT itemID, MAX(highestBid) AS MaxBid
FROM VW_SEARCH
WHERE highestBid > 0 OR highestBid IS NULL
GROUP BY itemID) VJ
ON VW.itemID = VJ.itemID AND VW.highestBid = VJ.MaxBid
This gave the following results (did not add result 5 - 1199 because it is all the same as result 4, this would happen in the actual table not the example table from above):
itemID title startPrice highestBid category endDate
1 1234 Alfa 25 26 PC 2018-09-22
2 5678 Bravo 9 20 Console 2018-07-03
3 9876 Charlie 84 85 Stamps 2018-06-14
4 NULL NULL NULL NULL NULL NULL
1200 1470 Delta 98 100 Fashion 2018-06-15
1201 9631 Echo 56 65 Cars 2018-06-25
While this is technicly allowing a NULL in the colums I need to get a result in the likes of :
itemID title startPrice highestBid catgory endDate
1 1234 Alfa 25 26 PC 2018-09-22
2 5678 Bravo 9 20 Console 2018-07-03
3 9876 Charlie 84 85 Stamps 2018-06-14
4 1470 Delta 98 100 Fashion 2018-06-15
5 9631 Echo 56 65 Cars 2018-06-25
6 7856 Foxtrot 98 NULL Dolls 2018-12-26
How do I get the desired result, or is it just impossible?
Also if the query could be written better, please say so.
Thanks in advance.
Solve the problem using a left join:
SELECT VW.itemID, VW.title, VW.startPrice, VW.highestBid, VW.category, VW.endDate
FROM VW_SEARCH VW LEFT JOIN
(SELECT itemID, MAX(highestBid) AS MaxBid
FROM VW_SEARCH
GROUP BY itemID
) VJ
ON VW.itemID = VJ.itemID AND VW.highestBid = VJ.MaxBid;
Or, use the ANSI-standard ROW_NUMBER() function:
select vw.*
from (select vw.*,
row_number() over (partition by itemID
order by highestBid nulls last
) as seqnum
from vw_search vw
) vw
where seqnum = 1;
This guarantees one row per item.
Note: Not all databases support NULLS LAST. This may not even be necessary, but you can also implement it using a case expression.
Can you give the definition of the view at least? Maybe the table definition too.
I would go only with subquery as because identity column :
select vw.*
from vw_search vw
where id = (select vm1.id
from vw_search vm1
where vm.itemID = vw1.itemID and vm1.highestBid is not null
order by vm1.highestBid desc
limit 1
);
However, some DBMS has not support LIMIT clause such as SQL Server if so, then you can use TOP clause instead.
I have a table with an ID and multiple informative columns. Sometimes however, I can have multiple data for an ID, so I added a column called "Sequence". Here is a shortened example:
ID Sequence Name Tel Date Amount
124 1 Bob 873-4356 2001-02-03 10
124 2 Bob 873-4356 2002-03-12 7
124 3 Bob 873-4351 2006-07-08 24
125 1 John 983-4568 2007-02-01 3
125 2 John 983-4568 2008-02-08 13
126 1 Eric 345-9845 2010-01-01 18
So, I would like to obtain only these lines:
124 3 Bob 873-4351 2006-07-08 24
125 2 John 983-4568 2008-02-08 13
126 1 Eric 345-9845 2010-01-01 18
Anyone could give me a hand on how I could build a SQL query to do this ?
Thanks !
You can calculate the maximum sequence using group by. Then you can use join to get only the maximum in the original data.
Assuming your table is called t:
select t.*
from t join
(select id, MAX(sequence) as maxs
from t
group by id
) tmax
on t.id = tmax.id and
t.sequence = tmax.maxs
Consider a system to track repairs. I have a table with customer data and a common id key. I have a second table with a column to show which type of repair part was used on each id key and how many were used. Their definitions are below:
order_information
order_id | cust_last_name
465 Smith
899 Williams
512 Johnson
345 Fenton
122 Bowles
944 Cooper
parts_usage
order_id | part_type | part_quantity
465 Part 1 5
465 Part 2 4
899 Part 1 2
899 Part 2 8
899 Part 3 6
512 Part 3 1
345 Part 2 4
345 Part 3 5
122 Part 2 3
944 Part 1 2
I'd like to run a query for reporting that will return the part's pieces broken out like so:
order_id | Part 1 | Part 2 | Part 3 | Total
465 5 4 9
899 2 8 6 16
512 1 1
345 4 5 9
122 3 3
944 2 2
Is it possible to do this with a query so that my reports can show how many of each part was used on each repair ticket?
As you can see, each order_id can have multiple part types and unique quantities. I want to break the different part types (I have 3 total) into 3 separate columns with their totals listed by order_id.
select order_id, [Part 1], [Part 2], [Part 3], Total
from
(
select oi.order_id
, part_type
, part_quantity
, Total = sum(part_quantity) over (partition by oi.order_id)
from order_information oi
inner join parts_usage pu on oi.order_id = pu.order_id
) as parts
pivot
(
sum(part_quantity) for part_type in ([Part 1], [Part 2], [Part 3])
) as pvt
order by order_id
This works for me.
I have ordered the resultset by order_id as well; there doesn't appear to be a specific order in your example results but it is mentioned in the question details.
You can see the key is to combine the PIVOT with a SUM aggregate window function.
SQL Fiddle with demo.