Posts Tagged ‘Window Functions’

Include other columns while doing aggregates and GROUP BY – MSDN TSQL forum

September 22, 2010 Leave a comment

–> Question:

I need maximum mark scored each students and min mark scored each students.

I have done this way…

select ID, max(mark), min(mark) 
from table1 
group by ID

But i need more field as Class…. I don’t want include class field in group by clause

–> My Answer:

Try joining the query with the table, like:

select T1.*, T2.ID, T2.max_mark, T2.min_mark
from table1 T1
join (select ID,max(mark) as max_mark,min(mark) as min_mark
	from table1 
	group by ID
) AS T2
on T1.ID=T2.ID


–> shaahs Answer:

In this situation you can use the window functions:

select ID, Class, 
	max(mark) over(partition by ID), 
	min(mark) over(Partition by ID) 
from table1

… in this cause you don’t want to include the fields in group by clause.