.net datasets expressions columns

Abraham · 16 Jan 2007 at 19:48

Hopefully this is just a quick q, basically just want to know if i can do what i want, and roughly how to do it

I have a table stored as an xml file and worked on using a dataset

for the sake of simplicity it has three columns: user_id, week_start, profit
I want to work out the average profit per user, and potentially per range of week_start for each user
the most sensible way i can see to do this if possible is to use an expression column, but can you use them in that way

any help/suggestions much appreciated

Abraham · 18 Jan 2007 at 13:56

no ideas on this?

i can obv do it by pulling the data out then averaging it, but the less data i have to pull into the application the better

happytechie · 18 Jan 2007 at 14:07

select sum(profit)/count(9), user_id from table group by user_id

or something like that...

Paul

Abraham · 18 Jan 2007 at 14:30

i've found that Compute() does exactly what i want

if anyone's interested the syntax is:

table.Compute("Avg(Total)", "UserID = x")
where obviously avg is the calculation i want to perform and userID = is the filter to say which ones i want it performed on
just randomly found it on an unrelated site by chance