You can simplify the definition of new BCSs and explicitly defined VVDSs by creating data classes for each. The data classes should specify the characteristics most commonly used at your installation. You can override most attributes defined in the data class when you issue the DEFINE command. You can use a data class to define the catalog even if the catalog is not SMS-managed.

For BCSs, choose appropriate default size and performance attributes. See Estimating Space Requirements for the BCS, Choosing Options to Adjust Catalog Performance, and Defining a Basic Catalog Structure for recommendations for BCS attributes. For RECORG, specify KS. Do not specify a key length or offset, or a logical record length. These values are set by the DEFINE USERCATALOG command.

For VVDSs, choose an appropriate size, usually 10 tracks primary and secondary space. There are no special performance attributes for VVDSs. For RECORG, specify ES. Allow DEFINE CLUSTER to set all other values.