I have three tables
1. players(id, first_name, last_name, age, position, team_id)
2. teams(id, team_name, stadium, wins, draws,defeats,goal_for,goal_against)
3. goals_scored(id, player_id, goal_time)
SQL statement
SELECT
players.first_name,
players.last_name,
teams.name,
players.position,
players.age,
COUNT(*) AS goals
FROM
players
JOIN goals_scored
ON players.id = goals_scored.player_id
JOIN teams
ON players.team_id = teams.id
GROUP BY players.id;
teams table
id team_name stadium wins draws defeats goal_for goal_against
1 APF Club Dasharath 7 2 7 29 25
players table
id first_name last_name position age team_id
4 Dipendra Shrestha forward 19 1
goals_scored table
id player_id goal_time
1 4 34
2 4 57
I want to group goals on players id so that I can get the count of goals of an individual player.
Like
first_name last_name team_name position age goals
Dipendra Shrestha APF Club forward 19 2
How can I do it?
Prefer to group on as few as possible columns, especially if multiple tables get involved so that a good index can be applied to handle the group by.
WITH GoalsPerPlayer (playerId, nrOfGoals)
AS
(
SELECT player_id, count(*)
FROM goals_scored
GROUP BY player_id
)
SELECT p.first_name, p.last_name, t.team_name, p.position, p.age, g.numberOfGoals as goals
FROM GoalsPerPlayer g
INNER JOIN players p ON p.id = g.player_id
INNER JOIN teams t ON t.id = p.team_id
Edit:
Fixed typo's in query as mentioned by PO in comment below.
WITH GoalsPerPlayer (playerId, nrOfGoals)
AS
(
SELECT player_id, count(*)
FROM goals_scored
GROUP BY player_id
)
SELECT p.first_name, p.last_name, t.team_name, p.position, p.age, g.nrOfGoals as goals
FROM GoalsPerPlayer g
INNER JOIN players p ON p.id = g.playerId
INNER JOIN teams t ON t.id = p.team_id
Your query basically looks fine. I would adjust the GROUP BY to be more complete:
SELECT p.first_name, p.last_name, t.name, p.position, p.age,
COUNT(*) AS goals
FROM players p JOIN
goals_scored gs
ON p.id = gs.player_id JOIN
teams t
ON p.team_id = t.id
GROUP BY p.first_name, p.last_name, t.name, p.position, p.age;
Related
I have a players table and a teams table and I am trying to find the youngest player in each team. I can find the youngest player:
SELECT lname, fname, dob, position
FROM players
WHERE dob = (SELECT MAX(dob) FROM players);
When I try to include the teams table I am receiving the same data as above, which is the youngest player overall. I am very new to this so I am still trying to understand multiple row subqueries. If I order by team name, I will receive the same output. Do I need another SELECT statement for the teams table as well? How would I go about doing that if so? Changing operator from IN to ALL or ANY will also give me the same output.
SELECT lname, fname, dob, position, name
FROM players p JOIN teams t ON p.team_id = t.id
WHERE dob IN (SELECT MAX(dob) FROM players);
I am working in LiveSQL if that helps.
You don't even need the teams table to just get the player information. A correlated subquery is sufficient:
SELECT p.lname, p.fname, p.dob, p.position
FROM players p
WHERE p.dob = (SELECT MAX(p2.dob)
FROM players p2
WHERE p2.team_id = p.team_id
);
You can introduce a JOIN to get the team name if you like:
SELECT p.lname, p.fname, p.dob, p.position, t.name
FROM players p JOIN
teams t
ON p.team_id = t.id
WHERE p.dob = (SELECT MAX(p2.dob)
FROM players p2
WHERE p2.team_id = p.team_id
);
You can use NOT EXISTS as follows:
SELECT LNAME, FNAME, DOB, POSITION, NAME
FROM PLAYERS P
JOIN TEAMS T
ON P.TEAM_ID = T.ID
WHERE NOT EXISTS (
SELECT 1
FROM PLAYERS P1
WHERE P1.TEAM_ID = P.TEAM_ID
AND P1.DOB < P.DOB
);
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 this tables:
Student - Id, FirstName, LastName, Age
Group - Id, Name
Student_Group - Student_Id, Group_Id
I need to find least group of student. I have tried many times. I would be so glad if somebody helped.
Have you tried to do
SELECT top 1 g.name
FROM group g INNER JOIN Student_group sg ON g.id = sg.Group_Id
WHERE count(sg.student_id) >0
ORDER BY count(sg.student_id)
GROUP BY sg.group_id
?
If you want also the groups with 0 students you should to do
SELECT top 1 g.name
FROM group g INNER JOIN Student_group sg ON g.id = sg.Group_Id
ORDER BY count(sg.student_id)
GROUP BY sg.group_id
--If you just need the group with the least members,
--Group By and Count will work to find the Group with the least members
--Then use select top 1 record and order by GroupCount Ascending
SELECT TOP 1 Group_Id, COUNT(Group_Id) AS [GroupCount]
FROM Student_Group
GROUP BY Group_Id
ORDER BY [GroupCount]
I have this SQL query that does a GROUP BY to merge together all rows that contain the same Player_id but not the same Game_id:
SELECT p.Player_id,
p.Name,
p.Position,
SUM(s.Goals) AS goalsb,
SUM(s.Assists) AS assistsb,
SUM(s.Points) AS pointsb
FROM Dim_Player AS p
INNER JOIN Fact_Statistics AS s ON s.Player_id = p.Player_id
GROUP BY p.Player_id, p.Name, p.Position
ORDER BY pointsb DESC, goalsb DESC
What I want to do is implant a COUNT each time the GROUP BY merges a row with another to create a new column called "Games played". Example:
Player_id Game_id goalsb
8470598 465 1
8470598 435 1
this will be grouped together with the SQL query above to become:
Player_id goalsb
8470598 2
But I want to have this:
Player_id goalsb Games_played
8470598 2 2
If you have repeating Game_id's and you'd like to count the distinct values, you can add a
COUNT (DISTINCT Game_id)
clause to your SELECT statement.
Add a count function to the select query. COUNT(*) counts each row in the group, independent of the columns selected.
SELECT p.Player_id, p.Name, p.Position, SUM(s.Goals) AS goalsb, SUM(s.Assists) AS assistsb, SUM(s.Points) AS pointsb, COUNT(*) as [Games_played]
FROM Dim_Player AS p INNER JOIN Fact_Statistics AS s ON s.Player_id = p.Player_id
GROUP BY p.Player_id, p.Name, p.Position, s.Game_id
ORDER BY pointsb DESC, goalsb DESC
Database structure:
Clubs: ID, ClubName
Teams: ID, TeamName, ClubID
Players: ID, Name
Registrations: PlayerID, TeamID, Start_date, End_date, SeasonID
Clubs own several teams. Players may get registered into several teams (inside same club or into different club) during one year.
I have to generate a query to list all players that have been registered into DIFFERENT CLUBS during one season. So if player swapped teams that were owned by the same club then it doesn't count.
My attempts so far:
SELECT
c.short_name,
p.surname,
r.start_date,
r.end_date,
(select count(r2.id) from ejl_registration as r2
where r2.player_id=r.player_id and r2.season=r.season) as counter
FROM
ejl_registration AS r
left Join ejl_players AS p ON p.id = r.player_id
left Join ejl_teams AS t ON r.team_id = t.id
left Join ejl_clubs AS c ON t.club_id = c.id
WHERE
r.season = '2008'
having counter >1
I can't figure out how to count and show only different clubs... (It's getting too late for clear thinking). I use MySQL.
Report should be like: Player name, Club name, Start_date, End_date
This is a second try at this answer, simplifying it to merely count the distinct clubs, not report a list of club names.
SELECT p.surname, r.start_date, r.end_date, COUNT(DISTINCT c.id) AS counter
FROM ejl_players p
JOIN ejl_registration r ON (r.player_id = p.id)
JOIN ejl_teams t ON (r.team_id = t.id)
JOIN ejl_clubs c ON (t.club_id = c.id)
WHERE r.season = '2008'
GROUP BY p.id
HAVING counter > 1;
Note that since you're using MySQL, you can be pretty flexible with respect to columns in the select-list not matching columns in the GROUP BY clause. Other brands of RDBMS are more strict about the Single-Value Rule.
There's no reason to use a LEFT JOIN as in your example.
Okay, here's the first version of the query:
You have a chain of relationships like the following:
club1 <-- team1 <-- reg1 --> player <-- reg2 --> team2 --> club2
Such that club1 must not be the same as club2.
SELECT p.surname,
CONCAT_WS(',', GROUP_CONCAT(DISTINCT t1.team_name),
GROUP_CONCAT(DISTINCT t2.team_name)) AS teams,
CONCAT_WS(',', GROUP_CONCAT(DISTINCT c1.short_name),
GROUP_CONCAT(DISTINCT c2.short_name)) AS clubs
FROM ejl_players p
-- Find a club where this player is registered
JOIN ejl_registration r1 ON (r1.player_id = p.id)
JOIN ejl_teams t1 ON (r1.team_id = t1.id)
JOIN ejl_clubs c1 ON (t1.club_id = c1.id)
-- Now find another club where this player is registered in the same season
JOIN ejl_registration r2 ON (r2.player_id = p.id AND r1.season = r2.season)
JOIN ejl_teams t2 ON (r2.team_id = t2.id)
JOIN ejl_clubs c2 ON (t2.club_id = c2.id)
-- But the two clubs must not be the same (use < to prevent duplicates)
WHERE c1.id < c2.id
GROUP BY p.id;
Here's a list of players for one season.
SELECT sub.PlayerId
FROM
(
SELECT
r.PlayerId,
(SELECT t.ClubID FROM Teams t WHERE r.TeamID = t.ID) as ClubID
FROM Registrations r
WHERE r.Season = '2008'
) as sub
GROUP BY PlayerId
HAVING COUNT(DISTINCT sub.ClubID) > 1
Here's a list of players and seasons, for all seasons.
SELECT PlayerId, Season
FROM
(
SELECT
r.PlayerId,
r.Season,
(SELECT t.ClubID FROM Teams t WHERE r.TeamID = t.ID) as ClubID
FROM Registrations r
) as sub
GROUP BY PlayerId, Season
HAVING COUNT(DISTINCT sub.ClubID) > 1
By the way, this works in MS SQL.
SELECT p.Name, x.PlayerID, x.SeasonID
FROM (SELECT DISTINCT r.PlayerID, r.SeasonID, t.ClubID
FROM Registrations r
JOIN Teams t ON t.ID = r.TeamID) x
JOIN Players p ON p.ID = x.PlayerID
GROUP BY p.rName, x.PlayerID, x.SeasonID
HAVING COUNT(*) > 1