SharePoint 2013
I have an External Content Type (ECT) defined for a table in a SQL Server database. I also have the usual CRUD methods defined for the ECT. The table has over 50 fields, but there is an ID field (an IDENTITY column) and a computed column called RefNumber which uses the ID field to generate a unique alphanumeric reference number. The RefNumber field is the Primary Key on the table.
In the Create method, I have omitted the ID and RefNumber fields as Input parameters. In the Return parameters page, there is a warning saying that the RefNo field is a Nullable type - I don't know if this is significant or not to the issue.
Users complete an InfoPath form bound to an external list associated with the ECT. Users can enter data for all other fields in the table, except the two fields mentioned above. On submitting the form, this error appears:
The data is still submitted to the SQL database, and the ID and RefNo values are generated fine.
What do I need to do to make this error to go away?