validation rule and triggers

Question

I have a field on case linked to an order that is present both in the case object and in the object order.

When the case field is true, the order field becomes true in a trigger (after insert or update). The case field cant be set to false after it has been set to true. I have written the following validation rule to do that: ISCHANGED(Field_c) && PRIORVALUE(Field__c) == true

But now I have to add this feature: when the field is set to true, another date field must be set to today date. Now my trigger is in after insert and upsert, therefore I cannot update the new case i am upserting.

I have 2 possible ways I believe: - modify the trigger leaving it in after mode and operating on the new case and updating the new case (is this acceptable?= - set the trigger in before mode but this way i would have to modify the validation rule cause it won't work anymore and i don't know how to fix it.

What do you suggest? Thanks

Answer 1

Although you cannot update trigger.new in the after context, you can still update the objects included in the trigger context variable. You just need to cache the values of trigger.new in a list. Then you can still update the values in that list.

Will give you an error as you cannot perform DML on trigger.new

trigger AccountTrigger on Account (after update) {

     for(Account a : trigger.new){
        a.Name = 'New Name';
     }
     update trigger.new;
}

Will not give an error as you are updating a list of Accounts, not trigger.new

trigger AccountTrigger on Account (after update) {

         list<Account> accounts2Update = new list<Account>();
         for(Account a : trigger.new){
            accounts2Update.add(new Account(
                 Id = a.Id,
                 Name = 'New Name'
            ));
         }
         update accounts2Update;
}

Answer 2

But now I have to add this feature: when the field is set to true, another date field must be set to today date. Now my trigger is in after insert and upsert, therefore I cannot update the new case i am upserting.

I think the simplest solution would be to use workflow based on ISCHANGED(Field_c) && PRIORVALUE(Field__c) == true. When this validation rule is triggered for the first time, you also want to set the other date field you mention to a value of today().