DSS2 — Service 9.6: Associate Regions For Updates

According to section 9.1.3.2, (a), if an instance attribute is associated with the default region, there is no value in also associating it with other regions, because the default region always overlaps with all other regions that have dimensions. An instance attribute should only be associated with the default region if it is not associated with any other region. When an instance attribute is associated with another region, its association with the default region should no longer exist. So, if an instance attribute is associated with the default region, associating that instance attribute with one or more other regions shall have the effect of removing the association of that instance attribute with the default region, because there is no way to explicitly remove the association of that instance attribute with the default region. Therefore, the Associate Regions For Updates service description, which now says that, "This service shall add the specified regions to the set of associations of each specified instance attribute" needs to be changed to indicate that if an instance attribute is associated with the default region, then invocation of the Associate Regions For Updates service shall remove the association of that instance attribute with the default region as well as add the association of that instance attribute to the specified region. This is the sole exception to the additive semantics rule.

Change the service description as suggested.