All three products use different models for managing devices and allocating disk space initially and later, reflecting the different uses for the products. For example:
In Adaptive Server Enterprise, you allocate space in database devices initially using DISK INIT and then create a database on one or more database devices. You can add more space using ALTER DATABASE or automatically, using thresholds.
In Sybase IQ, you initially allocate space by listing raw devices in the CREATE DATABASE statement. You can add more space manually using CREATE DBSPACE. Although you cannot add space automatically, you can create events to warn the DBA before space is actually needed. Sybase IQ can also use file system space. Sybase IQ does not support Transact-SQL DISK statements, such as DISK INIT, DISK MIRROR, DISK REFIT, DISK REINIT, DISK REMIRROR, and DISK UNMIRROR.
SQL Anywhere is similar to Sybase IQ, except that the initial CREATE DATABASE statement takes a single file system file instead of a list of raw devices. SQL Anywhere also lets you initialize its databases using a command utility dbinit, which Sybase IQ does not support.
For information on disk management, see the System Administration Guide: Volume 1.
