The adapters retrieve from the RDBMS only those rows or columns referenced in the FOCUS report request. Additionally, the adapters may pass to the RDBMS all of the work required to join, sort, and aggregate data. This reduces the volume of RDBMS-to-FOCUS communication, resulting in faster response times for adapter users.

The Adapter for DB2 fully supports the DB2 Distributed Data Facility. It appends a FOR FETCH ONLY clause to SELECT statements passed to DB2. This clause assists the DB2 optimizer in access path selection, and offers significant performance improvement in the distributed database environment. AUTODB2 also supports three-part table names. In addition, the adapter supports the IBM Distributed Relational Database Architecture™ (DRDA®). For a description of adapter DDF and DRDA support, see Additional Topics.