• External calls as part of data sync are made as @future calls: Salesforce has a limitation that it cannot trigger an external call when a CRUD operation is being performed as part of an inbound call (e.g. data sync from client). Any external call is queued and performed as future call. As a result, data synchronization cannot wait for the response of an external call before returning the data back to the client. You need to keep this limitation in mind when designing an external data integration.

• Do not delete and recreate data: As a best practice, data modified in salesforce because of external integration (e.g. From SAP, Siebel etc.) should be an update instead of a delete and insert. Deleting and inserting records may impact sync performance.

• Limit combined external integration call: It is also recommended that too many integration calls with an external system should be avoided wherever possible. It is recommended that you analyze the architecture and combine multiple calls together if possible.