Select multiple sums with MySQL query and display them in separate columns

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无人及你
无人及你 2021-01-02 03:38

Let\'s say I have a hypothetical table like so that records when some player in some game scores a point:

name   points
------------
bob     10
mike    03
mi         


        
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  • 2021-01-02 04:04

    In pure sql:

    SELECT
        sum( (name = 'bob') * points) as Bob,
        sum( (name = 'mike') * points) as Mike,
        -- etc
    FROM score_table;
    

    This neat solution works because of mysql's booleans evaluating as 1 for true and 0 for false, allowing you to multiply truth of a test with a numeric column. I've used it lots of times for "pivots" and I like the brevity.

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  • 2021-01-02 04:13

    This is called pivoting the table:

    SELECT SUM(IF(name = "Bob", points, 0)) AS points_bob,
           SUM(IF(name = "Mike", points, 0)) AS points_mike
    FROM score_table
    
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  • 2021-01-02 04:14

    you can use pivot function also for the same thing .. even by performance vise it is better option to use pivot for pivoting... (i am talking about oracle database)..

    you can use following query for this as well.. -- (if you have only these two column in you table then it will be good to see output else for other additional column you will get null values)

    select * from  game_scores
    pivot (sum(points) for name in ('BOB' BOB, 'mike' MIKE));
    

    in this query you will get data very fast and you have to add or remove player name only one place

    :)

    if you have more then these two column in your table then you can use following query

     WITH pivot_data AS (
                SELECT points,name 
      FROM   game_scores
      )
      SELECT *
      FROM   pivot_data
    pivot (sum(points) for name in ('BOB' BOB, 'mike' MIKE));
    
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  • 2021-01-02 04:20

    You can pivot your data 'manually':

    SELECT SUM(CASE WHEN name='bob' THEN points END) as bob,
           SUM(CASE WHEN name='mike' THEN points END) as mike
      FROM score_table
    

    but this will not work if the list of your players is dynamic.

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  • 2021-01-02 04:26
    SELECT sum(points), name
    FROM `table`
    GROUP BY name
    

    Or for the pivot

    SELECT sum(if(name = 'mike',points,0)),
           sum(if(name = 'bob',points,0))
    FROM `table
    
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  • 2021-01-02 04:28

    Are the player names all known up front? If so, you can do:

    SELECT SUM(CASE WHEN name = 'bob'  THEN points ELSE 0 END) AS bob,
           SUM(CASE WHEN name = 'mike' THEN points ELSE 0 END) AS mike,
           ... so on for each player ...
      FROM score_table
    

    If you don't, you still might be able to use the same method, but you'd probably have to build the query dynamically. Basically, you'd SELECT DISTINCT name ..., then use that result set to build each of the CASE statements, then execute the result SQL.

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