Syntax options:

    CACHE numeric-value| NOCACHE

    The CACHE clause specifies how many values of the sequence Oracle
    Rdb should preallocate and keep in memory for faster access.
    The mumeric value must be a value between 2 and 2147483647.
    You cannot cache more values than will fit in a given cycle of
    sequence numbers; thus, the maximum value allowed for the CACHE
    clause must be less than the value resulting from the following
    formula:

    (MAXVALUE-MINVALUE)/ABS(INCREMENT)

    You can alter the CACHE value if it is currently a value of 2
    or higher. When you alter the CACHE value, existing users of the
    sequence continue to use the original setting. You can use the
    SET FLAGS 'SEQ_CACHE' statement to adjust the cache size for a
    single process. See the See the SET_FLAGS statement for details.

    If NOCACHE is currently enabled or the CACHE value is 1, you can
    alter the CACHE value, but may have to wait until other users
    of the sequence have released locks on it. (Note that CACHE 1 is
    equivalent to NOCACHE.)

    A cache for a given sequence is populated at the first request
    for a number from that sequence, and whenever a value is
    requested when the cache is empty. If a system failure occurs,
    or when the cache is released any unfetched values will be
    discarded. The maximum number of lost values is equal to the
    current cache size. This may be the value specified by CACHE or
    by the SET FLAGS SEQ_CACHE option.

    The NOCACHE clause specifies that values will be allocated one
    at a time. This will require more I/O to the Rdb root file than
    using a CACHE value.

    Note that even after you alter the CACHE value, users who
    were using the sequence at the time you altered the CACHE will
    continue to use the original setting.