The ROW SNAPSHOT IS ENABLED (CACHE SIZE IS n ROWS) option enables
    storage of snapshot copies of rows within the cache and specifies
    the number of snapshot "slots" to allocate for the cache.

    The default for new caches, and existing caches is to have this
    feature disabled.

    If you do not specify the CACHE SIZE clause for the ROW SNAPSHOT
    IS ENABLED option, Oracle Rdb creates a cache that can contain up
    to 1000 snapshot rows.