Oracles function result cache (FRC) works, in simplified terms, by caching the result of a PL/SQL function. This can greatly improve performance, but it can also lead to performance problems.
Read More »Category: I/O efficiency
Forall is still row-by-row
I came over some code that used the forall construct to update rows in a large table. Quite a few rows were updated and the batch took some time to complete. Usually, using forall is a good idea, but sometimes other constructs can perform better.
Read More »Statistics gathering parameters for partitioned tables
When partitioned tables get a bit large, these parameters may be suitable to set.
Read More »Generating data: union all vs insert all
To test out different physical table lay-outs, I had to repeatedly generate some test-data. After a few runs, I wanted to speed it up a bit. This is how I did it.
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:
- nice theory... 