I am trying to essentially divide one count by a number I query from another table in SQL
MOVIECOUNT AS (
SELECT COUNT(MS.MOVID) AS MOVCOUNT, MG.GENRE AS GENREPERCOUNT
FROM MOVIESUCCESS MS
INNER JOIN MOVIES_GENRES MG ON MG.MOVIE_ID = MS.movid
group by MG.GENRE
)
SELECT (MC.MOVCOUNT / COUNT(DG.MOVIE_ID))
FROM MOVIECOUNT MC, DIRECTORS_GENRES DG
WHERE MC.GENREPERCOUNT = DG.GENRE
GROUP BY DG.GENRE
I can't get the latter part to compile (the MOVIECOUNT works--just there for reference). The rest of the schema isn't that important, and I have the rest of the code working.
I'm essentially just trying to get the count I found in moviecount (which is done per genre) and divide that by the count of all movies of the same genre. Ideas? Oracle SQL
You probably need to compute each aggregate separately before joining them:
with mgc as (
select
mg.genre,
count(*) as moviecount
from
moviesuccess ms
inner join
movies_genres mg
on mg.movie_id = ms.movid
group by
mg.genre
), dgc as (
select
dg.genre,
count(*) as directorcount
from
directors_genres dg
group by
dg.genre
) select
mgc.genre,
mgc.moviecount / dgc.directorcount
from
mgc
inner join
dgc
on mgc.genre = dgc.genre;
You can do this with the approach you are taking, you just have to be more careful with the aggregation:
WITH MOVIECOUNT AS (
SELECT COUNT(MS.MOVID) AS MOVCOUNT, MG.GENRE AS GENREPERCOUNT
FROM MOVIESUCCESS MS INNER JOIN
MOVIES_GENRES MG
ON MG.MOVIE_ID = MS.movid
group by MG.GENRE
)
SELECT (MC.MOVCOUNT / COUNT(DG.MOVIE_ID))
FROM MOVIECOUNT MC JOIN
DIRECTORS_GENRES DG
ON MC.GENREPERCOUNT = DG.GENRE
GROUP BY MC.GENRE, MC.MOVCOUNT;
Related
For each country, report the movie genre with the highest average ratings, and I am missing only one step that i cant figure it out.
Here's my current code:
SELECT c.code AS c_CODE, menres.genre AS GENRE, AVG(RATE) as AVERAGE_rate,MAX(RATE) AS MAXIMUM_rate, MIN(RATE) AS MINIMUM_rate from movirates
leftJOIN movgenres ON movgenres.movieid = movratings.movieid
left JOIN users ON users.userid = movrates.userid
left JOIN c ON c.code = users.city
LEFT JOIN menres ON movenres.genreid = menres.code
GROUP BY menres.genre , c.code
order by c.code asc, avg(rate) desc, menres.genre desc ;
You can use the ROW_NUMBER window function to assign a unique rank to each of your rows:
partitioned by country code
ordered by descendent average rating
Once you get this ranking, you may want to select all those rows which have the highest average rating (which are the same having the ranking equal to 1).
WITH cte AS (
SELECT c.code AS COUNTRY_CODE,
mg.genre AS GENRE,
AVG(rating) AS AVERAGE_RATING,
MAX(rating) AS MAXIMUM_RATING,
MIN(RATING) AS MINIMUM_RATING
FROM moviesratings r
INNER JOIN moviesgenres g ON g.movieid = r.movieid
INNER JOIN users u ON u.userid = r.userid
INNER JOIN countries c ON c.code = u.country
LEFT JOIN mGenres mg ON mg.code = g.genreid
GROUP BY mg.genre,
c.code
ORDER BY c.code,
AVG(rating) DESC,
mg.genre DESC;
)
SELECT *
FROM (SELECT *,
ROW_NUMBER() OVER(
PARTITION BY COUNTRY_CODE,
ORDER BY AVERAGE_RATING) AS rn
FROM cte) ranked_averages
WHERE rn = 1
Note: The code inside the common table expression is equivalent to yours. If you're willing to share your input tables, I may even suggest an improved query.
You should use window function in this case by using rank() then select the first rank only.
with mov_rates(c.code, genre, average, max, min)
as.
select c.code c_code,
e.genre genre,
avg (rate) avg
max (rate) max
min (rate) min
from movrates a
LEFT join movge.nres b on a.movieid = b.movieid
LEFT join users c on a.userid = c.user
LEFT join countr.ies d on c.code = d.code
left join mGenres e on b.genreid = e.code
group by d.country_code, e.x
),
rategenre (rank, c_code, genre, avgrate, max, min)
as
(
select rank() over (partition by c.c order by avgrates asc) rank,
country code,
genre,
average_r.ating,
maximum_rating,
minimum_.ating
from movrate \\just practicing on something
)
selec.t 2
from genre
where rank = 5
Reference:
OVER Clause
Please help, I want to merge this two query
I have 3 Tables (places,ratings,places_image)
places
id
name
description
ratings
id
rating
place_id
user_id
places_image
id
place_id
image
These are the 2 queries:
SELECT places.*, SUM(rating) AS total_rating,COUNT(ratings.user_id) AS total_user FROM ratings, places WHERE ratings.place_id = places.id GROUP BY places.id
SELECT places.*, places_images.image FROM places, places_images WHERE places.id = places_images.place_id GROUP BY places.id
Query 1
Query 2
I tried to do this query but it give duplicate data for the aggregate function
SELECT places.id, places.name, places.description, places_images.image ,SUM(rating) AS total_rating,COUNT(ratings.user_id) AS total_user FROM places_images JOIN places ON places_images.place_id = places.id JOIN ratings ON ratings.place_id = places.id GROUP BY places.id
Query 3
How can i combine it ?
You need to use 2 Inner Join on the place_id and user_id
It'll be something like
SELECT SUM(r.rating) AS total_ratings, COUNT(r.user_id) AS total_users
FROM ratings r
INNER JOIN places p ON p.id = r.user_id
INNER JOIN places_image pi ON pi.place_id = r.place_id
GROUP BY r.id
Seems the only thing i need is to subquery it
select a.*, d.image, b.totalRating, c.totalUser from places a, ( select place_id, sum(rating) AS totalRating from ratings group by place_id ) b, ( select place_id, count(id) AS totalUser from ratings group by place_id ) c, places_images d where c.place_id = a.id and b.place_id = a.id and d.place_id = a.id GROUP BY a.id
Result
Thank you very much, GBU
I am trying to solve 2 queries
Find all the actors that made more movies with Yash Chopra than any other director
Select b.number,b.actor,b.director from (select MAX(a.count) as number,a.director,a.actor from
(select count(p.PID) as count ,p.PID as actor,md.PID as director from person as p left join m_cast
as
mc on trim(p.PID)=trim(mc.PID) inner join m_director as md on trim(md.MID)=trim(mc.MID) group by
md.PID ,p.PID) as a group by a.actor) as b where b.director=(select PID from person where
Name='Yash Chopra')
report for each year the percentage of movies in that year with only female actors, and the total number of movies made that year. For example, one answer will be: 1990 31.81 13522 meaning that in 1990 there were 13,522 movies, and 31.81% had only female actors. You do not need to round your answer.
SELECT female_count.year Year,
((female_count.Total_movies_with_only_female_leads)*100)/total_count.Total Percentage FROM ((SELECT
movie.year Year,count(*) Total_movies_with_only_female_leads FROM movie WHERE NOT EXISTS ( SELECT *
FROM M_Cast,person WHERE M_Cast.mid = movie.MID and M_Cast.PID = person.PID AND person.gender='Male'
) GROUP BY movie.year) female_count, (SELECT movie.year,count(*) as Total FROM movie group by
movie.year) total_count) WHERE female_count.year=total_count.year
Unfortunately for both the queries, I am getting empty table. Can someone help me in solving these 2 queries
I wrote it using CTEs so it is more readable.
First Question:
WITH HowManyMoviesPerActorDirector AS
(select mc.pid as actorpid
,pa.name as actorname
,md.pid as directorpid
,pd.name as producername
,count(mc.MID) as numberofmovies
from m_cast as mc
inner join m_director md on md.MID=mc.MID
inner join person pa ON mc.PID=pa.PID
inner join person pd ON md.PID=pd.PID
group by mc.pid as actorpid,md.pid
)
select h.acorname
,h.producername
,h.numberofmovies
from HowManyMoviesPerActorDirector h
WHERE h.numberofmovies = (select MAX(h2.numberofmovies)
from HowManyMoviesPerActorDirector h2
where h2actorpid=h.actorpid
group by h2actorpid)
AND h.producername='Yash Chopra'
The second one:
WITH MoviesIncludingGendeflag AS
( select m.mid
,m.year
,sum(case when p.gender='female' then 0 else 1 end) as genderflag
from movie m
inner join mc_cast mc on mc.mid=m.mid
inner join person p on p.pid=mc.pid
group by m.mid,m.year
) FemaleOnlyMovies AS
( select m.year,count(m.id) as Total
from MoviesIncludingGendeflag m
where generflag=0
group by m.year
), TotalMovies AS
(
select m.year,count(m.id) as Total
from movie m
group by m.year
)
select TM.year,TM.Total,(COALESCE(FOM.Total,0)*100.0/TM.Total) as percentage
from TotalMovies TM
left join FemaleOnlyMovies FOM ON FOM.year=TM.year
I have a database which has these tables:
Users (id, email)
Trips (id, driver_id)
MatchedTrips (id, trip_id)
I need to get for each user the total number of trips he created divided by the total matches found.
I am stuck in building the raw SQL query for this. Here is what I tried, and sure it's far from being correct.
SELECT
users.email,
total_trips.count1 / total_matches.count2
FROM users CROSS JOIN (SELECT
users.email,
count(trips.driver_id) AS count1
FROM trips
INNER JOIN users ON trips.driver_id = users.id
GROUP BY users.email) total_trips
CROSS JOIN (SELECT users.email, count(matches.trip_id) AS count2
FROM matches
LEFT JOIN trips ON matches.trip_id = trips.id
LEFT JOIN users ON trips.driver_id = users.id
GROUP BY users.email) total_matches;
You can calculate total trips and total matches for each driver in the way like this:
select driver_id, count(t.id) as total_trips, count(m.id) as total_matches
from trips t
left join matches m on (t.id = trip_id)
group by 1
Use this query as a derived table in join with users:
select email, total_trips, total_matches, total_trips::dec/ nullif(total_matches, 0) result
from users u
left join (
select driver_id, count(t.id) as total_trips, count(m.id) as total_matches
from trips t
left join matches m on (t.id = trip_id)
group by 1
) s on u.id = driver_id
order by 1;
SQLFiddle.
The simplest way is probably to use count(distinct):
select u.email,
count(distinct t.id) as num_trips,
count(distinct m.id) as num_matches,
(count(distinct t.id) / count(distinct m.id)) as ratio
from users u left join
trips t
on t.driver_id = u.id left join
matches m
on m.trip_id = t.trip_id
group by u.email;
Note: If emails are unique, then the query can be simplified. count(distinct) can be expensive under some circumstances.
The following query is designed to find the number of people who went to a hospital, the total number of people who went to a hospital and the divide those two to find a percentage. The table Claims is two million plus rows and does have the correct non-clustered index of patientid, admissiondate, and dischargdate. The query runs quickly enough but I'm interested in how I could make it more usable. I would like to be able to add another code in the line where (hcpcs.hcpcs ='97001') and have the change in percentRehabNotHomeHealth be relfected in another column. Is there possible without writing a big, fat join statement where I join the results of the two queries together? I know that by adding the extra column the math won't look right, but I'm not worried about that at the moment. desired sample output: http://imgur.com/BCLrd
database schema
select h.hospitalname
,count(*) as visitCounts
,hospitalcounts
,round(count(*)/cast(hospitalcounts as float) *100,2) as percentRehabNotHomeHealth
from Patient p
inner join statecounties as sc on sc.countycode = p.countycode
and sc.statecode = p.statecode
inner join hospitals as h on h.npi=p.hospitalnpi
inner join
--this join adds the hospitalCounts column
(
select h.hospitalname, count(*) as hospitalCounts
from hospitals as h
inner join patient as p on p.hospitalnpi=h.npi
where p.statecode='21' and h.statecode='21'
group by h.hospitalname
) as t on t.hospitalname=h.hospitalname
--this where exists clause gives the visitCounts column
where h.stateCode='21' and p.statecode='21'
and exists
(
select distinct p2.patientid
from Patient as p2
inner join Claims as c on c.patientid = p2.patientid
and c.admissiondate = p2.admissiondate
and c.dischargedate = p2.dischargedate
inner join hcpcs on hcpcs.hcpcs=c.hcpcs
inner join hospitals as h on h.npi=p2.hospitalnpi
where (hcpcs.hcpcs ='97001' or hcpcs.hcpcs='9339' or hcpcs.hcpcs='97002')
and p2.patientid=p.patientid
)
and hospitalcounts > 10
group by h.hospitalname, t.hospitalcounts
having count(*)>10
You might look into CTE (Common Table Expressions) to get what you need. It would allow you to get summarized data and join that back to the detail on a common key. As an example I modified your join on the subquery to be a CTE.
;with hospitalCounts as (
select h.hospitalname, count(*) as hospitalCounts
from hospitals as h
inner join patient as p on p.hospitalnpi=h.npi
where p.statecode='21' and h.statecode='21'
group by h.hospitalname
)
select h.hospitalname
,count(*) as visitCounts
,hospitalcounts
,round(count(*)/cast(hospitalcounts as float) *100,2) as percentRehabNotHomeHealth
from Patient p
inner join statecounties as sc on sc.countycode = p.countycode
and sc.statecode = p.statecode
inner join hospitals as h on h.npi=p.hospitalnpi
inner join hospitalCounts on t.hospitalname=h.hospitalname
--this where exists clause gives the visitCounts column
where h.stateCode='21' and p.statecode='21'
and exists
(
select p2.patientid
from Patient as p2
inner join Claims as c on c.patientid = p2.patientid
and c.admissiondate = p2.admissiondate
and c.dischargedate = p2.dischargedate
inner join hcpcs on hcpcs.hcpcs=c.hcpcs
inner join hospitals as h on h.npi=p2.hospitalnpi
where (hcpcs.hcpcs ='97001' or hcpcs.hcpcs='9339' or hcpcs.hcpcs='97002')
and p2.patientid=p.patientid
)
and hospitalcounts > 10
group by h.hospitalname, t.hospitalcounts
having count(*)>10