Using multiple files in a dbspace allows your Sybase IQ and temporary data to be distributed across multiple operating system files or partitions. Multiple files improve throughput and reduce average latency for the dbspace.
When possible, allocate all files when you create a dbspace to ensure even data distribution.
If you add files later, use the ALTER DBSPACE command to add the additional files to the dbspace. Sybase IQ stripes new data across both old and new dbspaces. Striping may even out, or it may remain unbalanced, depending on the type of updates you have. The number of pages that are “turned over” due to versioning has a major impact on whether striping is rebalanced.