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Greg RohmanGreg Rohman 

Preventing an Insert/Update trigger based on value of a field

Hello.

 

I'm currently updating my Salesforce data from a mySQL database utilizing a 3rd party integration tool. There are some records, though, that may exist in the mySQL database that I don't want updated in Salesforce. Is there some way to perhaps set a flag in a Salesforce record that would prevent updated information from populating in Salesforce? Perhaps comparing Trigger.Old and Trigger.New and rolling back to the previous values?

 

Thanks.

 

-Greg

jrotensteinjrotenstein

Yes, that's exactly what you'd do. You'd want something like:

 

trigger SelectiveImport on Opportunity (before update) {
for (Opportunity new_o : Trigger.new) {
if (new_o.DoNotUpdate__c) {
new_o.Field1__c = Trigger.oldMap.get(new_o.id).Field1__c;
}
}
}

  • I've used Opportunity in this example, you could use any object
  • You only need this logic for before update, since you need an existing record to check for the flag
  • The field you want to revert is called Field1__c in this example
  • I use Trigger.oldMap.get(Id) because I once read that there's no guarantee that Trigger.new[] exactly matches Trigger.old[], but that might be old-fashioned of me

 

That technique is very useful for 'overriding' required fields. For example, upserting an Opportunity requires a Close Date and StageName. If you don't want to override them during the import, use the above logic to revert the values back to their current value.