18.4.8.4.5 ETag Support

Learn about ETag support.

When a BOSS business object defines a history attribute of type historyType='versionNumber' then the object will have an ETag returned in the response payload in the selector $context.etag. The BOSS adapter defines an APEX$ETAG column in the data profile mapped to this $context.etag selector, and including the Additional Information annotation tag of ETag. At runtime, the BOSS adapter will include a non-null ETag value with update and delete operations as expected by the BOSS runtime. When configuring APEX regions like form or interactive grid based on a REST Data Source for a BOSS object with an ETag, developers must set the Lost Update Type to the value Row Version Column and choose APEX$ETAG for the row version column name. Alternatively, to have BOSS perform the lost update protection only on the server-side, you can disable APEX's lost update protection on a form or grid region when it's using a REST Data Source for a BOSS object that has an ETag.