OAM collection names provide another level of grouping called a collection. A collection is a group of objects that share a common storage group and have the same default initial storage class and management class attributes. All objects within a collection must have unique names. However, you can have two objects with identical names if the objects belong to separate collections.

OAM collections are cataloged in integrated catalog facility (ICF) catalogs using OAM collection names. An individual object does not have an entry in the catalog.

Each object is a member of a collection and each collection is part of one storage group. A collection does not span storage groups. OAM identifies an object by its collection name and its object name. An object is described by an entry in a DB2® object directory. A collection is described by an MVS collection name catalog entry and a corresponding OAM collection identifier table entry.

OAM provides two primary interfaces for processing objects: the application program interface (OSREQ) and the OAM Storage Management Component (OSMC). Both address objects using the object's collection name and object name including those cases where the object must be identified to the ACS routines for the STORE (OSREQ), CHANGE (OSREQ), and CTRANS (OSMC class transition) environments. Refer to z/OS DFSMS OAM Planning, Installation, and Storage Administration Guide for Object Support and z/OS DFSMS OAM Application Programmer's Reference for more information.