Use of GROUP BY twice in MySQL

Question

My table looks like this.

Location    Head    Id  IntTime
1           AMD     1   1
2           INTC    3   3
3           AMD     2   2
4           INTC    4         


        

Answer 1

I am not sure how your sample result arrived at Location = 7 for ARMH, for instance. Try this...

SELECT MIN(Location), Head, Id, MIN(IntTime)
FROM test
GROUP BY Head, Id