Shared pool library cache and DB Buffer cache doesn't make too much sense to me because :
1. If just one DB user issues a big FTS or long run SQL, Oracle in order to make enough room to cache all retrieving block in library cache must age out probably everything that already be there, so it means that even one wrong sql can reset the whole thing which was already cached for raiy days ?????????????
2. And for take benefit of Shared Pool Library cache : Two SQL statement must be EXACTLY the same till dumb Oracle can utilize existing parsed plan in library cache for the second coming similar sql.
could you explain what happen in real DB life ??
