Salesforce - Refer custom field from standard object in custom object

Question

I have a custom object. I would like to refer the custom field from opportunity object in my custom object as a read only field. How to do that?

Answer 1

You'd need some relation between the 2 tables in database. For example if you add a lookup field in your custom object, call it Opportunity__c & populate it on few recods, then you can display Opportunity Name but also reference other Opportunity fields in reports or formula fields. You could make another field (type = formula and then pick what matches the field you're interested in, text, date, checkbox...). Make the formula similar to Opportunity__r.MyCustomFieldOnOpportunity__c and you're good to go.

If you can't define any sensible relation between Opp and your custom object you'd have to tell us what exactly you try to achieve. Perhaps there's config (or code) way to copy values across. But making a lookup field and then a formula that jumps through this lookup is the most natural way.