On a company project that I'm working on, we found a performance issue on fetching a very small dataset (about 77 rows). After some research I've found the existence of this oci8's flag which fixes this issue.
Just to exemplify, the forementioned query speed dropped from 6~7 seconds to 0.15s.
To prevent that another one dismiss the sequel library for this kind of problem, I suggest a default value to this flag. By the way, the oracle_enchanced adapter for ActiveRecord already have this same default value (from where I stealed), so I don't think that it will do any harm :)
PS: Sorry about my bad english
Add a default 'prefetch_rows' value for oracle adapter
This looks good to me. I think I do run with :prefetch_rows when I test on Oracle, so having it set by default makes sense.