Parameters that control the characteristics of database storage
    area files. You can specify most storage area parameters for
    either single-file or multifile databases, but the effect of the
    clauses differs.

    o  For single-file databases, the storage area parameters
       specify the characteristics for the single storage area in
       the database.

    o  For multifile databases, the storage area parameters specify
       a set of default values for any storage areas created by
       the CREATE DATABASE statement that do not specify their own
       values for the same parameters. The default values apply to
       the RDB$SYSTEM storage area, plus any others named in CREATE
       STORAGE AREA database elements.

       The CREATE STORAGE AREA clauses in a CREATE DATABASE statement
       can override these default values. The default values do
       not apply to any storage areas created later with the ALTER
       DATABASE statement.