MS Access Calc Field with combined fields - ms-access

Question

I have been trying to resolve this calc field issue for about 30 mins, it looks like I have the single field conditions correct in the expression such as [points] and [contrib] but the combined ([points]+[contrib]) field is not meeting the requirement that sets the field to the correct member type, so when these are added it returns some other member type as basic. Might I use the between operator with the added fields...? I tried it, but there is some compositional error. So in other words if you got 45 points it sets you to basic only named in the points field, if you have contrib of 45 you are set to basic in the calc field as expected, but if it were 50 + 50, instead it is setting to basic when it should be "better" member label. Otherwise this simple statement should seem to be correct but the computer is not reading it so when adding. It must not be recognizing the combined value for some reason and calc fields do not have a sum() func.
Focus here: (([points]+[Contrib]) >= 45 And ([points]+[Contrib]) < 100),"Basic",
IIf(([points] >=45 And [points]<100) Or ([Contrib] >=45 And [Contrib] <100) Or (([points]+[Contrib]) > = 45 And ([points]+[contrib] < 100),"Basic",
IIf(([points] >=100 And [points] <250) Or ([Contrib] >=100 And [Contrib] <250) Or ((([points]+[Contrib]) >=100) And (([points]+[Contrib])<250)),"Better",
IIf(([points] >=250 And [points]<500) Or ([Contrib] >=250 And [Contrib] <500) Or ((([points]+[Contrib]) >=250) And (([points]+[Contrib])<500)),"Great",
IIf(([points] >=500) Or ([Contrib] >=500) Or (([points]+[Contrib]) >=500),"Best","Non-member"))))

Answer 1

Here is a data sample from an Access 2010 table which includes a calculated field named member_type:
id points Contrib member_type
-- ------ ------- ----------
1 1 1 Non-member
2 50 1 Basic
3 200 1 Better
4 300 1 Great
5 600 1 Best
If that is what you want for your calculated field, here is the expression I used for member_type:
IIf([points]+[Contrib]>=45 And [points]+[Contrib]<100,'Basic',IIf([points]+[Contrib]>=100 And [points]+[Contrib]<250,'Better',IIf([points]+[Contrib]>=250 And [points]+[Contrib]<500,'Great',IIf([points]+[Contrib]>=500,'Best','Non-member'))))
In case I didn't get it exactly correct, here is that same expression formatted so that you can better see where you need changes:
IIf([points]+[Contrib]>=45 And [points]+[Contrib]<100,'Basic',
IIf([points]+[Contrib]>=100 And [points]+[Contrib]<250,'Better',
IIf([points]+[Contrib]>=250 And [points]+[Contrib]<500,'Great',
IIf([points]+[Contrib]>=500,'Best','Non-member'
))))
Note if either points or Contrib is Null, member_type will display "Non-member". If that is not the behavior you want, you will need a more complicated expression. Since a calculated field expression can not use Nz(), you would have to substitute something like IIf([points] Is Null,0,[points]) for every occurrence of [points] and IIf([Contrib] Is Null,0,[Contrib]) for [Contrib]
It would be simpler to prohibit Null for those fields (set their Required property to Yes) and set Default Value to zero.

Answer 2

The BETWEEN operator returns TRUE if the value you are testing is >= or <= the limits you have for BETWEEN.
If you are looking at 50+50 then that total = 100 and you are Between 44 and 100. That would result in an answer of "Basic". Change the range for ([points]+[Contrib]) Between 44 And 100) to be ([points]+[Contrib]) Between 44 And 99)