z/TPF collection support (z/TPFCS) contains all the components that you need to access
collections. The z/TPFCS database consists of user-defined
data stores. In these data stores are collections. Each collection consists of elements. Elements
can contain character data, binary data, structures, or references to other collections or z/TPF files. The z/TPFCS database will handle collection sizes from 0 to 2,147,483,647
elements.
To relate the concept to familiar terms, you might say that an
element could be a record, a file could be a collection, and a related
set of files could be a data store. All of these files put together
are the z/TPFCS database.
Figure 1 shows the general layout of a z/TPFCS database:
Figure 1. General layout of a z/TPFCS database
The following are some key points to remember about a z/TPFCS database:
The basic subsystem (BSS) contains a directory for all data stores,
including ones stored on other subsystems.
The database contains user-defined data stores as well as multiple
data stores.
The database is anchored with two #IBMM4 records (one is a shadow,
or copy, of the other).
The database is initialized with the ZOODB INIT command.
