Oracles function result cache (FRC) can in certain cases give a considerable performance boost. Application context is another useful feature. How does FRC work when the function result relies on context-settings? And how can we make them play well together?
Large joins may use full scans and hash joins. If your tables are large enough, this will fill up your process working memory and start spilling to your temp-tablespace. At that time a few important effects come into play:
Lately I’ve been working a lot with large bulk-loads of data between Oracle databases. The loading is done over db-links and we needed to speed up some of the loads since parallel DML is not supported in distributed transactions.