Calculation field - change type from Number to Text silently fails

Discussion created by danshockley on Oct 28, 2016
Latest reply on Jun 27, 2018 by TSGal

Product and version: FileMaker Pro Advanced 15.0.2)

OS and version: Mac OS X 10.10.5 (Yosemite)

Hardware: any

Description: When defining options for a Field, changing the "Calculation result is" type from Number to Text appears to work, but reverts without notice or warning when you hit OK on the calculation dialog. This happens when there is a Summary field that uses the Calculation field you are trying to change.

How to replicate:

  1. In a brand new or existing database, make a calculation field named, for example, "WasNumberCalc", set the calculation result type to Number, and put in some numeric calculation (e.g. 123).
  2. Make a summary field that gets a Total (or any other numeric function) of the WasNumberCalc field.
  3. Forget that you made that Summary field.
  4. Open the options for WasNumberCalc and change its calculation result type to: Text.
  5. Hit OK. You have at this point received no errors.
  6. Click options for WasNumberCalc again.
  7. Observe that the calculation result type silently reverted to Number.


Workaround (if any):

Always double-check that changes you've made (without receiving any errors) actually worked.

Or, never forget that you made a summary field that refers to a field you were still testing.

Or, remove or re-target any summary fields before changing the calculation.


Note that, when you try to change a NON-calculation Number field to a Text field and a Summary field was using it, FileMaker refuses to let you change it and provides the following error message:


This field’s type cannot be changed because it is used by “MySummaryField”.


That is what should happen when you hit OK in the Calculation dialog after changing the calculation field's result from Number to Text. You should be given an error message, not have the change appear to work but be silently ignored.