Question

so I have this table:

ID  INITIAL_DATE    TAX
A   18-02-2012      105
A   19-02-2012      95
A   20-02-2012      105
A   21-02-2012      100
B   18-02-2012      135
B   19-02-2012      150
B   20-02-2012      130
B   21-02-2012      140

and what I need is, for each distinct ID, the highest TAX ever. And if that TAX occurs twice I want the record with the highest INITIAL_DATE.

This is the query I have:

SELECT   ID, MAX (initial_date) initial_date, tax
    FROM t t0
   WHERE t0.tax = (SELECT   MAX (t1.tax)
                       FROM t t1
                      WHERE t1.ID = t0.ID
                   GROUP BY ID)
GROUP BY ID, tax
ORDER BY id, initial_date, tax

but I want to believe there is a better way of grouping these records.

Is there any way of NOT grouping by all the columns in the SELECT?

Answer 1

Have you tried with analytical functions?:

SELECT t0.ID, t0.INITIAL_DATE, t0.TAX
FROM (  SELECT *, ROW_NUMBER() OVER(PARTITION BY ID ORDER BY TAX DESC , INITIAL_DATE DESC) Corr
        FROM t) t0
WHERE t0.Corr = 1