user interface validations

The component will use the current value at the time. This is also a UX best practice because users should be aware of issues upon load. The other option is to run validation upon submission of a form instead of at the component level.

If your rule would accept a null value as a valid value, would that problem not go away?

Hi,

This is my understanding, ex: you submitted a new request with a filed (Ex: Property Number) value as 123, this filed have a validation to make sure user is not entering a property number value which is already in the system. I think the issue you are facing after submitting the request, when you try to edit the same request by default it is throwing validation error, since your validation checks the current value against the data base values (Here your expectation is  we shouldn't show validation message since this is an existing request and user didn't modify the value). If this is what you are issue is, You need to update your validation logic to skip validation if it is an existing request and user didn't modify any value

Try this logic, it should work.

a!localVariables(
  local!initialValue: a!refreshVariable(
    /*save your rule input value here on load*/
    value: ri!propertyNumber,
    refreshOnReferencedVarChange: false
  ),
  /*Existing number to compare - */
  local!existingNumbers: {345, 678, 199},
  {
    a!textField(
      label: "Property Number",
      value: ri!propertyNumber,
      saveInto: ri!propertyNumber,
      validations: {
        if(
          and(
            a!isNotNullOrEmpty(ri!propertyNumber),
            local!initialValue <> ri!propertyNumber,
            contains(local!existingNumbers, ri!propertyNumber)
          ),
          "This ID is exist",
          ""
        )
      }
    )
  }
)

Great explanation. Thank you so much.