Provides an explicit file specification for storage area files.
    The CREATE STORAGE AREA clause creates two files: a storage area
    file with a file extension of .rda, and a snapshot file with a
    file extension of .snp. If you omit the FILENAME argument, the
    file specification takes the following defaults:

    o  Device: the current device for the process

    o  Directory: the current directory for the process

    o  File name: the name specified for the storage area

    Neither the file specification for the storage area nor the
    snapshot file may contain a node specification.

    The file specification is used for both the storage area and
    snapshot files that comprise the storage area (unless you use the
    SNAPSHOT FILENAME argument to specify a different file for the
    snapshot file). Because the CREATE STORAGE AREA clause can create
    two files with different file extensions, do not specify a file
    extension with the file specification.

    You may use a logical name for all or part of a file
    specification.

    One benefit of a multifile database is that its files can reside
    on more than one disk. If you want storage area files to reside
    on another disk, you must specify the FILENAME argument with a
    full file specification.

    However, you may choose to create a multifile database even
    if your main purpose in creating the storage area is not to
    distribute storage area files across more than one disk. For
    instance, a multifile database enables you to:

    o  Take advantage of hashed indexes. Hashed indexes require a
       storage area with mixed page format and cannot be stored in
       the RDB$SYSTEM storage area.

    o  Set attributes such as page size to better correspond with
       tables that will be stored in the storage area.