Sorts of RIDs

To perform list prefetch, Db2 sorts RIDs into ascending page number order. This sort is very fast and is done totally in memory.

Begin program-specific programming interface information. A RID sort is usually not indicated in the PLAN_TABLE, but a RID sort normally is performed whenever list prefetch is used. The only exception to this rule is when a hybrid join is performed and a single, highly clustered index is used on the inner table. In this case SORTN_JOIN is 'N', indicating that the RID list for the inner table was not sorted. End program-specific programming interface information.