如何获取多列的最大值（以及datecolumn为max的stringcolumn的值）并将其组合为单个查询？

Question

How can I do this in SQL?

This is my sample data:

ColA   ColB   ColC   ColD   ColE
----   ----   ----   ----   ----
TR12   25     67    yey
TR11   28     99    apr     2/2/2013
TR12   78     55    apr     2/2/2013
TR12   20     35    olf     2/5/2013

The condition is to get the max value in ColB and ColC of a certain value in ColA.

For ColD and ColE values, I would like to get them from the line where it has a maximum ColE value.

 ColA   ColB   ColC   ColD   ColE
 ----   ----   ----   ----   ----
*TR12*  25     *67*  yey
 TR11   28     99    apr     2/2/2013
 TR12   *78*   55    apr     2/2/2013
 TR12   20     35    *olf*   *2/5/2013*

Hence, my expected result would be like this:

ColA   ColB   ColC   ColD   ColE
----   ----   ----   ----   ----
TR12   78     67     olf    2/5/2013

This is all I have as of now where it could return the correct max value of a column, but what about returning a string based on the line where ColE is max value ? I am getting an incorrect value when I do max() function for ColD. I am getting the other word instead of the word where ColE is max.

SELECT 
   ColA, max(ColB) as ColB, max(ColC) as ColC,
   max(ColD) as ColD, -- this is where I got it wrong,
      this should return the string where its ColE is the maximum
   max(ColE) as ColE
FROM 
   dbo.SomeTable 
WHERE 
   ColA = 'TR12'

I really hope you could help me with this one..

thanks for the quick replies..

Answer 1

You are doing fine; just keep going. The max() aggregate function works on strings as well as numerics.