Re: tutorial incorrect calculation want to understand

[Phillip Ward]

Your "select" and your "group by" don't match.

SELECT 
  s.yearID 
, s.teamID 
, SUM(s.salary) 
, t.W  
, SALARY / t.W 
. . . 
GROUP BY s.teamID

Anything that you select that isn't in an aggregate function (sum, count, etc.) must be included as a "level" within your grouping. If you don't, then you get all sorts of odd results, just like this, because MySQl doesn't know how to roll things up - you haven't told it.

Try something more like this:

SELECT 
  s.teamID 
, SUM( s.salary ) AS SALARY 
, SUM( t.W ) AS WINS 
, SUM( s.salary / t.W ) AS CPW 

from       salaries  s 
inner join teams  t 
      on   s.teamID = t.teamID 
      and  s.yearID = t.yearID 

where s.yearID = 2002 

group by s.teamID 
order by salary desc 
;