Microsoft Access: How to do IF in Calculated Field Expression?

I want my calculated field to have a conditional value like this: if fieldA is 0 then set fieldC to 0 else field C = fieldB开发者_Python百科 / fieldA

How do I do this? Thanks.

And while you are at it, how do I do this in an Access VBA routine so that I can keep on revising my conditions.

In a table definition: not possible.

As a query:

SELECT
  IIF(FieldA = 0; 0; FieldB / FieldA) AS FieldC
FROM
  ATableWithFieldAAndFieldB

As SQL text in VBA: replace the ; with ,

You can add a procedure like this to your module code...

Public Function CalculateFieldC(ByVal fieldA as Long, ByVal fieldB as Long) as Single
  If fieldA = 0 Then
    CalculateFieldC = 0
  Else: CalculateFieldC = fieldB / fieldA
  End If
End Function

Then call it from an SQL statement; for example:

SELECT fieldA, fieldB, CaculateFieldC(fieldA, fieldB) AS fieldC
FROM aTableWithFieldAandFieldB;