By default, UniBasic files are restricted to a maximum of 2 GB, which is the maximum file size supported by most Unix operating systems. On some platforms such as Linux or AIX, Universal files can be created as "huge" files with the "" attribute. Such files can grow much larger than 2 GB. It may be necessary to configure special operating system or file system options in order to use huge files.

Users can restrict Index file dynamic expansion by setting the PREALLOCATE environment variable to 128.