As time goes by: When joins spill to disk

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:

Continue reading “As time goes by: When joins spill to disk”

Speeding up large data-transfers over a db-link

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.

Continue reading “Speeding up large data-transfers over a db-link”