Get count of games and display the players who played half of games - sql

Question

i Need help in these tables, i want SQL statement to give me this :
the players who played in half or more of the games, lets assume that we have 6 different games in 'GameType' table ... So I want to display all players who played 3 or more games.
like :
ID surName number of games played
1 test1 3
2 test2 4
3 test3 3
4 test4 6
this what i done until now:
SELECT dbo.Player.ID, dbo.Player.surName, count(DISTINCT
dbo.PlayerInAGame.gameTypeName) AS games_played, count(DISTINCT
dbo.Game.gameTypeName) AS games_count
FROM dbo.Player INNER JOIN
dbo.PlayerInAGame ON dbo.Player.ID =
dbo.PlayerInAGame.playerID INNER JOIN
dbo.Game ON dbo.PlayerInAGame.gameTypeName = dbo.Game.gameTypeName AND
dbo.PlayerInAGame.gameDateTime = dbo.Game.gameStartDateTime
GROUP BY dbo.Player.ID, dbo.Player.surName, dbo.Game.DealerInGame
here is the tables:
create table Dealer
(
number int identity(1000,1) primary key,
firstName nvarchar(20) not null,
surName nvarchar(20) not null,
birthDate date not null,
startWorkingDate date not null,
ID char(9) check(ID like replicate('[0-9]',9)) not null unique,
check(datediff(year,birthDate,startWorkingDate)>=24)
)
create table GameType
(
name nvarchar(20) primary key,
description nvarchar(20) not null,
minimumPlayers tinyint check (minimumPlayers > 0) not null,
maximumPlayers tinyint check (maximumPlayers > 0) not null,
check(minimumPlayers <= maximumPlayers)
)
create table Game
(
gameTypeName nvarchar(20) references GameType(name) on delete cascade,
gameStartDateTime datetime,
gameEndTime time,
DealerInGame int not null references Dealer(number),
primary key(gameTypeName,gameStartDateTime)
)
create table Player
(
ID char(9) primary key,
firstName nvarchar(20) not null,
surName nvarchar(20) not null,
city nvarchar(20) not null,
birthDate date check(datediff(year,birthDate,getdate())>=18) not null,
preferred nvarchar(20) references GameType(name) on delete set null
)
create table PlayerInAGame
(
playerID char(9) references Player(ID),
gameTypeName nvarchar(20),
gameDateTime datetime,
betAmount int check(betAmount>0) not null,
winLosAmount int,
check((winLosAmount = -betAmount) or (winLosAmount>=betAmount)),
foreign key(gameTypeName,gameDateTime) references
Game(gameTypeName,gameStartDateTime), primary
key(playerID,gameTypeName,gameDateTime) )
create table PlayerDealerRelation
(
dealerNumber int references Dealer(number) on delete cascade,
playerID char(9) references Player(ID),
relationType char(1) check(relationType in ('P','G','B','C','U','N')),
primary key(dealerNumber,playerID)
)

Answer 1

If your query in the question gives you the correct count, then it is very easy to add an extra filter that would leave only those rows where games_played is more than half of games_count.
Just add HAVING:
SELECT
dbo.Player.ID,
dbo.Player.surName,
count(DISTINCT dbo.PlayerInAGame.gameTypeName) AS games_played,
count(DISTINCT dbo.Game.gameTypeName) AS games_count
FROM
dbo.Player
INNER JOIN dbo.PlayerInAGame ON dbo.Player.ID = dbo.PlayerInAGame.playerID
INNER JOIN dbo.Game
ON dbo.PlayerInAGame.gameTypeName = dbo.Game.gameTypeName
AND dbo.PlayerInAGame.gameDateTime = dbo.Game.gameStartDateTime
GROUP BY dbo.Player.ID, dbo.Player.surName, dbo.Game.DealerInGame
HAVING
count(DISTINCT dbo.PlayerInAGame.gameTypeName) >
count(DISTINCT dbo.Game.gameTypeName) / 2