Update source from Database to Salesforce

Issue 1 : How to update Salesforce using update source when there are no fields to map with the external Id of Salesforce from database table.

Description: This happens when you try to integrate from Salesforce to Database, Lets say there is no external id of Salesforce to map with primary key of a table in db then you cannot update status back to Salesforce.

Resolution : Create a Rule which would process data from Salesforce to Database along with Salesforce Id, Then Add one more Rule and use update operation to bring back the Salesforce Id from database, By this way we can successfully update the status back to Salesforce.

Issue 2 : Can we map the external ID of Salesforce with the primary key of a database table to update back the status of Salesforce. 

Description : Lets say we have an external ID field of order object of Salesforce(Order_external_ID__c) which a DBSync user would like to map with the SeqNo ( primary key and auto generated) field of a database table. So, whenever a new order in inserted into database DBSync gets SeqNo to update back to Salesforce on success map that in turn will not be visible in Salesforce.

Resolution :  Since SeqNo field is an auto number in table of database so we advise not to advise to map with external id of Salesforce as it does not hold the value we provide externally. You should only map the externalID (Order_external_ID__c) to some other field in database then after sync you can get the field value that can be used to update back to Salesforce.