mysql - SELECT specific rows when using GROUP BY -


I have the following SQL table that tracks the user's score at a specific time. The user can have several digits per day. 

  + ------- + ------------ + ------- + - ---- + | User | Date | Score | ... | + ------- + ------------ + ------- + ----- + | Bob | 2014-04-19 | 100 | ... | | Mary | | 2014-04-19 | 100 | ... | | Alice | 2014-04-20 | 100 | ... | | Bob | 2014-04-20 | 110 | ... | | Bob | 2014-04-20 | 125 | ... | | Mary | 2014-04-20 | 105 | ... | | Bob | 2014-04-21 | 115 | ... | + ------- + ------------ + ------- + ----- +   
 A special form Users given (say  bob ),  how do I prepare a report for each user's score, but should I use the highest rated score per day?  (Getting the specific line with the highest score is also important with the highest score)  
  SELECT * FROM from `user_score` to WHERE 'user` =' bob 'by group' Date`   
 The base query that I am closing turns the result into the following result set:  
  + ------- + ------------ + ------- + - --- + | User | Date | Score | ... | + ------- + ------------ + ------- + ----- + | Bob | 2014-04-19 | 100 | ... | | Bob | 2014-04-20 | 110 | ... | | Bob | 2014-04-21 | 115 | ... | + ------- + ------------ + ------- + ----- +   
  The high score of  125  to  2014-04-20  is missing. I tried to make sure that `user_score` from  maximum   SELECT *, MAX (score) with the maximum (score) where 'user' = 'bob' The group returns the highest score for the day, but it is not the row in which the highest score is the other column values ​​of that row are important,  
 < code> + ------- + ------------ + ------- + - ---- + ------------ + | User | Date | Score | ... | Maximum (score) | + ------- + ------------ + ------- + ----- + ------------ + | Bob | 2014-04-19 | 100 | ... | 100 | | Bob | 2014-04-20 | 110 | ... | 125 | | Bob | 2014-04-21 | 115 | ... | 110 | + ------- + ------------ + ------- + ----- + ------------ + < Finally, I tried  
  SELECT *, MAX (score) with 'user_score` where' user '=' bob 'and score = maximum (points) group' date`   
 but the result is in invalid use of  GROUP BY .  
     
  •  Is on the right track, am I trying to complete, but I do not know the specific score to filter.   
     Edit:  
     SQLFiddle:   
     
     < p> If you want all the fields, then the easiest (faster way) in MySQL is not  present :  
      select 'user_score' to 'us' = 'Bob' is not (select 1 from user_scrow where we have us 2. 'user' = us.` user 'and us2.date = us .date and us2.score & gt; us.score);   
     It may look like a strange perspective and, I agree that it is. What it's doing, it's very easy: "Get all the rows from me  user_score  for Bob where there is no high score (for Bob)". This is equal to getting the line with the maximum score. With an index on  user_score (name, score) , this is probably the most effective way of doing what you want.

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