Specifies the number of storage areas for which slots are
    reserved in the database. The number of slots for storage areas
    must be a positive number greater than zero.

    You can use the RESERVE STORAGE AREA clause to reserve slots
    in the database root file for future use by the ADD STORAGE
    AREA clause of the ALTER DATABASE statement. Storage areas can
    be added only if there are storage area slots available. Slots
    become available after a DROP STORAGE AREA clause or a RESERVE
    STORAGE AREA clause.

    The number of reserved slots for storage areas cannot be
    decreased once the RESERVE clause is issued. If you reserve 5
    slots and later reserve 10 slots, you have a total of 15 reserved
    slots for storage areas.

    If you do not specify the RESERVE STORAGE AREA clause, the
    default number of storage areas is zero.