4.33Likely interview question
“What's the difference between Create, Update and Upsert?”
Answer:
“Create always intends to insert a new Salesforce record. Update targets an existing Salesforce record, normally by Salesforce ID. Upsert uses an external identifier to decide whether to insert or update, which is especially useful for repeatable integration synchronization and idempotency.”
“Why use an External ID?”
“It lets the integration address Salesforce records using the source system's stable business identifier rather than maintaining a separate Salesforce-ID mapping, and it enables upsert behavior.”
“Would you query before every upsert?”
“No. If the sole purpose of the query is determining whether the record exists and I have a reliable External ID, that's exactly what upsert removes. I'd query first when downstream state is actually needed for a business decision.”
“Normal API or Bulk API?”
“For transactional and relatively small synchronous operations I'd use the normal connector operations. For large imports, migrations, or synchronization workloads I'd consider Bulk API v2 because the workload is job-oriented and designed for large record volumes.”
“What do you retry?”
“Primarily transient failures such as connectivity and timeouts. I wouldn't blindly retry validation or schema errors, and I'd make sure the operation is idempotent because a timeout doesn't guarantee Salesforce didn't already commit the request.”
That last answer is particularly good.