h2 and embedded java sql file db

i have to admit there’s no good embedded java sql file db actually. i tested h2 yesterday and  h2 was good before the tuple was over 20,000. db access speed is scaled by O(n). and it showed heap error finally. aside the deadly critical table lock problem in concurrent situation, it cannot be used for real world db solution.

i know h2 is very good db, fastest and easy to use(with hibernate). i was impressed much. but when i need some db for embedded log system, h2 is not the product i have to adopt.

so there’s 3 ways  to solve this problem.
1. use derby(is there any other file base sql java db?)
2. use berkeley db java edition, this is not sql base
3. use non-java sql file db

derby is too slow, and buggy.. berkeley db’s structure is very different  and i have to redesign the entire or at least half of application. i’m not sure what is a good non-java sql file db. and non-java solution is also hard to maintain with servlet solution. there’s no time, so i have to decide  asap.. good luck to me~

P.S. i found some good discussion about this topic
http://www.h2database.com/ipowerb/index.php?s=58737509ee010033b0743b7a55a6f957&showtopic=331&st=0&

it seems that postgresql is the best solution, though it’s not a java db. but, i may choose the 4th option. 4. find a way with h2 -_-;;