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
    numeric value must be 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)

    The SET FLAGS option SEQ_CACHE can be used to override the
    setting of CACHE at runtime. See the SET_FLAGS statement for
    more details.

    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.

    By default, Oracle Rdb caches 20 sequence values.