Each application database file is a standard sequential (PS) file, subject to the same rules as any other PS file. As a BASIC type file, it is limited to 16 extents per volume, and no more than 65535 tracks on one volume. This file can be allocated on as many as 59 volumes if needed. If more than 65535 tracks are needed on a volume, allocating the file with DSNTYPE=LARGE will allow up to 16,777,215 tracks on a single volume. CA Datacom does not support Extended Format files, but using DSNTYPE=LARGE should meet most application needs.