如何在SQL查询中返回0值？

Question

How many (sum) goals were scored by each footballer in a given tournament in ascending order. For those footballers with 0 goals, we should return name of the footballer with value 0. Point being, footballers with 0 goals should also be part of output.

Footballer name | Goal  | Tournament
Messi           |    3  | La liga
Ronaldo         |    5  | UEFA
Suarez          |    2  | La liga

Output should be for 'La Liga' output should be:

Ronaldo  0
Suarez   2
Messi    3

Answer 1

Try this

select footballer, sum(goals)
from (
   select footballer, CASE
   WHEN tournament = 'LA_LIGA' THEN goals
     else 0 
   END 
   from tableA) AS tabA
group by footballer

Hope it help.

Answer 2

I'm not sure what's the structure of your database, I think normally the score is rewarded to a team instead of individuals. Anyway, here is just the concept:

Tables:

1. Players = {playerID, name, age, gender, height, etc..}

2. Games = {gameID, playerID, score...}

3. Tournaments = {tournamentID, gameID, tournamentName...}

     select p.name, IFNULL(g.score,0), t.tournamentName from players p left join Games g on p.playerID = g.playerID left join Tournaments t on g.GameID = t.GameID where t.tournamentName = 'La liga' 

Solution: My point is you may need to use IFNULL(..) and set the default value to 0.

Answer 3

try this....

Select FootballerName, 
sum(CASE WHEN tournament = 'LA LIGA' THEN Goal  else 0 END) as Goal 
from #Matches group by FootballerName

want to get all goals by players in all tournament

Select FootballerName, sum(Goal) as Goal 
from #Matches group by FootballerName

want to know goals touranmentwise

Select FootballerName, sum(Goal) as Goal,Tournament 
from #Matches group by FootballerName,Tournament

Answer 4

Unless you have 3 tables (players, tournaments, and goals) you'll need to create 3 sets using subselects and join them together. You need the cross-product of all tournaments and all footballers.

SELECT footballer_name, tournament FROM
    (SELECT DISTINCT footballer_name FROM your_table) AS players
  JOIN
    (SELECT DISTINCT tournament FROM your_table) AS tournaments

The above should get you one record per unique pairing of footballer and tournament. See if you can get this working in your database and then finish it off with a final join for scores

Answer 5

Source Of Information: Pivot query help us to generate an interactive table that quickly combines and compares large amounts of data. We can rotate its rows and columns to see different summaries of the source data, and we can display the details for areas of interest at a glance. It also help us to generate Multidimensional reporting.

Create Table script

Create table Matches(FootballerName varchar(100),Goal int ,Tournament varchar(100))

Sql Server Insert Records script

insert into Matches(FootballerName,Goal,Tournament)
select 'Messi ', 3 ,'La liga' union
select 'Ronaldo ', 5 ,'UEFA' union
select 'Surez ', 2 ,'La liga'

MySql Server script

   Create table Matches(FootballerName varchar(100),Goal int ,Tournament varchar(100));
insert into Matches(FootballerName,Goal,Tournament)
select 'Messi ', 3 ,'La liga' union
select 'Ronaldo ', 5 ,'UEFA' union
select 'Surez ', 2 ,'La liga';

MYSQL Version

Select FootBallerName,
Sum(CASE WHEN Tournament= 'La liga' THEN goal ELSE 0 END) AS 'La liga',
Sum(CASE WHEN Tournament= 'UEFA' THEN goal ELSE 0 END) AS 'UEFA'from Matches 
group by FootBallerName order by FootBallerName;

SQL Server Query using Pivot --- for Only [La liga]

SELECT FootballerName,isnull([La liga],0) as'La liga'
FROM (
    SELECT 
        FootballerName  ,isnull(goal,0) as'goal', 
        Tournament
    FROM Matches
) as s
PIVOT
(
    SUM(goal)
    FOR Tournament IN ([La liga],[UEFA])
)AS pvt order by [La liga]

SQL Server Query using Pivot --- Only [La liga] and [UEFA]

SELECT FootballerName,isnull([La liga],0) as'La liga',isnull([UEFA],0) as'UEFA'
FROM (
    SELECT 
        FootballerName  ,isnull(goal,0) as'goal', 
        Tournament
    FROM Matches
) as s
PIVOT
(
    SUM(goal)
    FOR Tournament IN ([La liga],[UEFA])
)AS pvt order by [La liga],[UEFA]

You can read more [ https://technet.microsoft.com/en-us/library/ms177410(v=sql.105).aspx]