storing database on memory

Question

i work on a web application (in java) which need to save the database in memory(cache...) and not in disk(C:// or D://). i try to use Java Cashing System, but it cannot execute queries because it is a cache and isn't a database. i try to use hibernate, but i have questions about it before use it:

1. where the hibernate save the database in memory or in disk?
2. if hibernate can't save the database on memory, which database can i use to save on memory?

thank you.

Answer 1

Also you can use JavaDB (formerly Derby) : http://www.javaquizplayer.com/blogposts/blogpost6.html

Answer 2

You can try HSQL http://hsqldb.org/ or H2 http://www.h2database.com/html/main.html. Both have in-memory mode. You can use Hibernate to work with both of them