Question

I can’t understand the difference between count and sum

I’m trying to get the number of rows for a specific condition of my report and always I get 0 using count or sum

columnA columnB
0       my string  
0       none
0       my string  
0       none
1       none

=IIF((Fields!columnA.Value = "0" and Fields!columnB.Value = "none"), SUM(Fields!columnA .Value),0)

I want to get 2 as a result
I can’t see my error

Answer 1

SUM() will return the total of the values in that field, while count will return the number of non null values.

So in the example you provided, =SUM(Fields!columnA.value) should return 0 and =COUNT(Fields!columnA.value) should return 5. [ But your IIF statement makes it sound like this is in a location where the scope is a single row, so then the count and Sum will only be applied to that row. If you want to scope the expression for the entire group, add a scope parameter to your aggregate function, such as COUNT(Fields!columnA.value, "MyDataSetName") ]

Since you aren’t seeing this result, there are a few things you can check:

• Are you really getting back 0 for your query, or is it possible that
  you are getting a null value back?
• Are you using this expression
  somewhere where the scope matches what you expect? That is, if you
  want it to count all rows in your data set are you using it in a top
  level textbox or group total?

Also, simplify to debug: place the individual components of your IIF statement in different cells, so that you can verify that the values match what you think should be happening.