Hi,

 

I had my xwiki linux pc crash on me during a powercut and the HSQLDB database seemed to revert to content that was on the xwiki several weeks ago.

What's happened? Does hsqldb store data in memory and that is why the data has got lost when the power went? I thought it stored the data in xwiki_db.script? Anyone?

It depends how you configured HSQLDB. AFAIK xwiki configures it by default to store to files and not in memory... Now it probably has a cache for performance reasons but several weeks of data loss looks like another issue. I'd recommend talking to the HSQLDB guys on their forums/mailing list. They're the best to know how to fix this I think.

We also recommend making regular backups of your database same as you would backup any of your personal files. For HSQLDB it's especially easy since you just have to save a directory. I know, it's too late now for you but if that can help others...

Thanks

-Vincent