validation rule issue its not working as expected

Question

Below is the validation rule

(TEXT(Full_Care_Confirmed__c)) == 'Yes'
&&
(
((ISPICKVAL(CPQ_Order_Type__c,'Corporate-Full Care Equipment Domestic'))
||
ISPICKVAL(CPQ_Order_Type__c,'Corporate-Full Care International')
||
ISPICKVAL(CPQ_Order_Type__c,'Corporate-Full Care Demo Equipment Accept')
||
ISPICKVAL(CPQ_Order_Type__c,'Canada-Full Care Equipment')))

IF full care confirmed picklist field is set to YES then CPQ_Order_Type__c picklist value should be any of the above

Answer 1

Validation rules trigger an error when the result is TRUE. This means you need to invert the logic with the NOT operator.

ISPICKVAL(Full_Care_Confirmed__c,'Yes')
&& NOT(
ISPICKVAL(CPQ_Order_Type__c,'Corporate-Full Care Equipment Domestic')    ||
ISPICKVAL(CPQ_Order_Type__c,'Corporate-Full Care International')         ||
ISPICKVAL(CPQ_Order_Type__c,'Corporate-Full Care Demo Equipment Accept') ||
ISPICKVAL(CPQ_Order_Type__c,'Canada-Full Care Equipment')
)

Answer 2

You can not set the value of a field using Validation Rule. The purpose of validation rule is to show error when some condition matches. For your requirement , you will need to use Process Builder or Workflow rule