The Hawk The Hawk - 6 months ago 60
SQL Question

SQL Get Other Rows From Aggregate Function

I have an aggregate function that does a group by (col A). It selects the maximum value from a set of columns(col B), but I also want to return another value from a column in the same row(col C). But if it groups 3 rows it selects the first value from column C not the column with the maximum (MAX(col B)).

1 75 jkl
1 100 abc
1 125 dae
2 200 def
3 300 ghi

"SELECT A, MAX(B), C FROM myTable where B > 50 GROUP BY A"

returns (first row) A => 1, B => 125, C => jkl

I want it to return

A => 1, B => 125, C => dae


You will want to use a subquery that will get the max(b) by each A and then join that value back to your table to return the remaining columns that match the values of the subquery:

select *
from mytable t1
inner join
  select A, max(b) B
  from mytable
  where b >50
  group by a
) t2
  on t1.a = t2.a
  and t1.b = t2.b
where t1.b >50

See SQL Fiddle with Demo