Question

Data:

Name | Score | Date
==
John | 10 | 09/01/2012
John | 20 | 09/01/2012
John | 5 | 09/01/2012
Frank | 20 | 11/01/2012

I want to run an SQL statement that will pull only the highest score from each day only, so I don’t want three scores from one date, only the highest. So the return I’d like from SQL would be:

John  | 20 | 09/01/2012    
Frank | 20 | 11/01/2012

Is it possible to do this via SQL, currently I can do it after pulling everything by checking dates. But would be great if it’s possible to do it direct from the DB.

I have tried a few solutions but as Date and Score aren’t distinct, as I want the highest I am unsure of where to proceed. The SQL is being used with a MS Access database.

Answer 1

Here’s a complete example. I did it in Oracle, so you might have to tweak the syntax a bit for Access.

CREATE TABLE tbl1 (NAME VARCHAR2(100), score INT, Dt DATE);

INSERT INTO tbl1 VALUES ('John',10,to_date('20120901','YYYYMMDD'));
INSERT INTO tbl1 VALUES ('John',20,to_date('20120901','YYYYMMDD'));
INSERT INTO tbl1 VALUES ('John',5,to_date('20120901','YYYYMMDD'));
INSERT INTO tbl1 VALUES ('Harry',15,to_date('20120901','YYYYMMDD'));
INSERT INTO tbl1 VALUES ('Frank',20,to_date('20121101','YYYYMMDD'));


select a.dt
     , b.name
     , a.score
  FROM (SELECT dt
             , MAX(score) score
          FROM tbl1
       GROUP BY dt) a
     , (SELECT NAME
             , dt
             , MAX(score) score
          FROM tbl1
       GROUP BY name, dt) b
  WHERE a.dt = b.dt
    AND a.score = b.score       

Output:

1   11/1/2012   Frank   20
2   9/1/2012    John    20

Note that if two people have highest score for given day, it will print them both. For example:

INSERT INTO tbl1 VALUES ('John',10,to_date('20120901','YYYYMMDD'));
INSERT INTO tbl1 VALUES ('John',20,to_date('20120901','YYYYMMDD'));
INSERT INTO tbl1 VALUES ('John',5,to_date('20120901','YYYYMMDD'));
INSERT INTO tbl1 VALUES ('Harry',20,to_date('20120901','YYYYMMDD'));
INSERT INTO tbl1 VALUES ('Frank',20,to_date('20121101','YYYYMMDD'));


select a.dt
     , b.name
     , a.score
  FROM (SELECT dt
             , MAX(score) score
          FROM tbl1
       GROUP BY dt) a
     , (SELECT NAME
             , dt
             , MAX(score) score
          FROM tbl1
       GROUP BY name, dt) b
  WHERE a.dt = b.dt
    AND a.score = b.score       

Output:

    DT          NAME    SCORE
1   11/1/2012   Frank   20
2   9/1/2012    John    20
3   9/1/2012    Harry   20