Sybase provides procedures and utilities that let you to upgrade your database.
Review the migration procedures in Database Upgrades and plan your migration. Follow the work flows for the type of database you want to migrate. There are separate migration paths for simplex and multiplex databases.
Uninstall Sybase IQ 15.x before you install Sybase IQ 15.4. Use the Control Panel to remove Sybase IQ 15.x, and then proceed as if you were installing Sybase IQ for the first time.
Upgrade your client tools. Although you can use the current version of the client tools to connect to an earlier 15.x server, some options, tools, and objects may not be available.