Question

I have a table that essentially has:

person  activity-code  activity-value

There are multiple activity-codes (about 17 of them) and activity-values per person. For exmaple:

A  1   10
A  1   12
A  2   4
B  1   5
B  2   3
B  2   8

What I want is a select statement that returns something like:

A   22 4
B   5  11

So the first column is the person. The second column is the sum of all activity-values for the activity-code 1 for that person. The third column is the sum of all activity-values for the activity-code 2 for that person. etc…

In the end I want to do this and use the OUTFILE command in there as I want to dump the totals to a file to be imported into an excel file.

It seems like there is a subquery in there somewhere but I am not advanced enough to figure that out.

Any help would be greatly appreciated. I can add detail if that is going to help.

Answer 1

Unfortunately for you, Mysql lacks the pivot command present in other databases, which makes this sort of thing a piece of cake. You’re stuck with something like

 select
      person,
      sum(case activitycode when 1 then activityvalue else 0 end),
      sum(case activitycode when 2 then activityvalue else 0 end),
      ....
 from 
      yourtable
 group by
      person