How to restrict Number fields in Validation rule

Question

I have Custom Object called "Review", with the formula field as

(Culture_fit__c  +  Experience__c  +  Leadership_Skills__c  
 + IF(
         Recommend_For_hire__c, 5, 1
     ) 
) /4. 

with Number data type

(Culture_fit__c  +  Experience__c  +  Leadership_Skills__c ) 

given value as (18,0) to all 3 data types.

My requirement is, without changing a value in datatype, I have to restrict the value to less than (10,0) to each field using the "Validation Rule". When a user tries to enter a value in New Record it should restrict the user to enter less than 10 Value in each field and calculate as per Formula expression.

Answer 1

I would push back on this requirement. Although there are ways we can restrict field length in a validation rule, the more appropriate place to do this is in the field definition itself.

Taking data constraints out of the field definition violates the principle of least astonishment.

If you're dead set on doing this the hard way (i.e. using a validation rule), the documentation on formula functions will be indispensable. You'd probably need to use text() to turn your number into a string, and regex() to verify that there are 0 decimals (i.e. no "." in the resulting string).

You could probably use ^\\d{0,10}$ as the regular expression.

Honestly though, fight to keep this as part of the field definition.

Answer 2

As per your question given field length is 18,0 but when user trying to enter more than 10 numbers it should throw error. correct? and you have to control all the 3 fields.

Please see below for validation rule and update your Field API name instead of NumberOfEmployees and update the restrict count which you have required.

LEN( TEXT(NumberOfEmployees)) > 10

Answer 3

The validation rule for a Number field having a value between 0 and 10 is very simple:

OR(My_Field__c < 0, My_Field__c > 10)

It can be made to apply to more than one field by repeating these comparisons in additional OR() arguments:

OR(My_Field__c < 0, My_Field__c > 10, My_Other_Field__c < 0, My_Other_Field__c > 10, ...)

Changing the data type would not help you in this case even if you could: you can set the number of decimals available on the field, but can't constrain the values further. Setting the data type to 2 places would only clamp the value at 99.