Question

I have the following table in MS Access 2007:

customer | Promotion |  Month   | activator | request_date | activation_date
   1     |   promo1  |   10     |   shop1   |  11/10/2011  |   21/10/2011  
   2     |   promo2  |   9      |   shop1   |  10/09/2011  |   15/09/2011  
   3     |   promo2  |   9      |   shop2   |  10/09/2011  |   16/09/2011
   4     |   promo1  |   10     |   shop1   |  12/10/2011  |   13/10/2011

What I need is a query to calculate the average number of days that each shop takes to activate each promotion grouped by month. So for example one result would be:

shop1 in October took an average of 10+1/2 days to activate promo1.

Thanks in advance!

Answer 1

SELECT activator, Month, Promotion, AVG(activation_date - request_date)
FROM ...
GROUP BY activator, Month, Promotion